Tag: fabric specification

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How to Write a Fabric Specification: A Contract Guide

A fabric specification is the document that tells everyone downstream, upholsterer, contractor, client, fire officer, exactly what fabric is being used and what it must achieve. A vague specification is where contract projects go wrong. This guide sets out what a complete fabric specification contains and what certificates to require. For where each decision falls in the project timeline, see our RIBA Plan of Work fabric guide.

What a Complete Specification Contains

A specification that prevents disputes states every performance requirement explicitly rather than assuming it. The core fields are the fabric name and range, the fibre composition, the abrasion requirement as a Martindale figure, the fire standard in full (for example BS 7176 Medium Hazard, not just Crib 5), the cleaning code required for the environment, the light fastness grade, and the colourway with a dye-lot reservation instruction for larger orders. For patterned fabric, add the pattern type and repeat. For each requirement, state the standard and the figure, not a general word like durable or fire-safe.

State the Standard in Full

The most common specification weakness is naming a standard loosely. Crib 5 alone is weaker than BS 5852 Ignition Source 5 (Crib 5). Fire-rated is meaningless without the standard. A Martindale requirement should give the figure, 100,000 rubs, not high abrasion. The fuller the reference, the less room for a substitution or a dispute later. State the standard, the part, and the figure for every performance field.

What Certificates to Require

For any contract project, require the independent test certificate before the fabric is installed, not a supplier’s claim of compliance. For fire, that means the certificate from a UKAS-accredited laboratory naming the fabric, the filling used in the test, the standard, and the result. A verbal assurance or a product description is not a certificate. For a composite standard such as BS 7176, confirm the certificate names the specific foam, because the certificate is valid only for the fabric and filling combination tested. For marine work, require the IMO certificate for the relevant part. For how FR certification works and who can issue it, see our how FR treatment works guide.

Confirm the Composite and the Cleaning Regime

Two checks prevent most late-stage failures. First, confirm the foam or filling matches the fire certificate, since substituting a different foam invalidates it. Second, confirm the fabric’s cleaning code suits the environment’s actual cleaning regime, an S-coded fabric fails in a setting that uses water-based cleaning. Present the environment’s cleaning products to the supplier and get written confirmation of compatibility. For the cleaning implications in demanding settings, see our healthcare fabric guide and hotel fabric specification guide.

Request Cuttings Before Committing

A cutting confirms colour, handle, and quality before the fabric is committed to a scheme, and provides the reference sample for matching later deliveries against. Request cuttings early, and for a phased order retain the first-delivery sample to check subsequent dye lots. For cuttings, dye lots, and lead-time planning, see our lead times and colour matching guide. For the full specification library organised by environment, application, and performance need, see our fabric buying guide by purpose.

Quick answers

What should a fabric specification include?
A complete fabric specification states the fabric name and range, the fibre composition, the Martindale abrasion figure, the fire standard in full (for example BS 7176 Medium Hazard), the cleaning code, the light fastness grade, and the colourway with a dye-lot reservation instruction for larger orders. For patterned fabric it adds the pattern type and repeat. Every performance requirement should give the standard and the figure, not a general word such as durable or fire-safe.


What certificates should I require before installing a contract fabric?
Require the independent test certificate before installation, not a supplier’s claim of compliance. For fire, that is the certificate from a UKAS-accredited laboratory naming the fabric, the filling used in the test, the standard, and the result. For a composite standard such as BS 7176, confirm the certificate names the specific foam, because it is valid only for the fabric and filling combination tested. For marine work, require the IMO certificate for the relevant part.


Why does the foam matter for a fire certificate?
Contract fire standards such as BS 5852 Crib 5 and BS 7176 test the fabric and filling together as a composite, not the fabric alone. A certificate is valid only for the specific fabric and foam combination tested. If the project uses a different foam from the one named in the certificate, the certificate does not cover the installation, and new testing is required. Always confirm the foam matches the certificate before ordering.

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Fabric Specification Glossary for Interior Designers

Mohair Velvet Upholstery Silk

This glossary defines the fabric specification terms interior designers and architects meet most often, grouped by subject. Each entry links to the full guide where the term is covered in depth. For the complete specification library, see our fabric buying guide by purpose.

Durability and Abrasion

Martindale. The UK and European abrasion test, expressed as a rub count. The higher the count, the more abrasion the fabric withstands. Contract grade begins at 40,000 rubs. See our Martindale rub test guide.

Wyzenbeek. The US abrasion test, expressed in double rubs. Not comparable to Martindale and not interchangeable with it on a UK specification. See our Wyzenbeek vs Martindale guide.

Pilling. The formation of small fibre balls on a fabric surface through rubbing. Graded by ISO 12945-2. Distinct from abrasion failure. See our pilling resistance guide.

Fire and FR

BS 5852 Crib 5. The UK fire standard for contract upholstery, testing the fabric and filling as a composite against a wooden crib ignition source. See our Crib 5 guide.

BS 7176. The specification standard for non-domestic seating that references Crib 5 and adds hazard categories and a water-soak stage. Medium Hazard is standard for hotels.

BS 5867. The fire standard for contract curtains, separate from and not interchangeable with the upholstery standards. See our contract curtain guide.

Inherent vs topical FR. Inherent fire resistance is a property of the fibre and is permanent. Topical treatment is applied after weaving and can degrade with cleaning. See our how FR treatment works guide.

IMO FTP Code. The marine fire framework for commercial vessels. Part 8 covers upholstery, Part 7 curtains, Part 9 bedding. Crib 5 does not substitute for it. See our marine fabric specification guide.

Colour and Light

Light fastness. A fabric’s resistance to fading under light, graded 1 to 8 on the Blue Wool Scale (ISO 105-B02). Grade 6 or above is needed for sun-exposed positions. See our light fastness guide.

Crocking. Colour transfer from a fabric surface through rubbing, tested by ISO 105-X12. See our colour fastness and crocking guide.

Dye lot. A record of a specific dyeing batch. Colour varies between dye lots, so a large or phased order should be secured from one lot. See our lead times and colour matching guide.

Metamerism. When two colours match under one light source but differ under another. See our colour naming and specification guide.

Cleaning Codes

W. Water-based cleaning is suitable. S. Solvent-based dry cleaning only; water can damage the fabric. WS. Either water or solvent cleaning is suitable. X. Vacuum or brush only; no wet or solvent cleaning. See our fabric care symbols and cleaning codes guide.

Construction and Materials

Velvet. A construction, not a fibre: a pile fabric that can be woven from mohair, cotton, silk, linen, or synthetic. Fibre determines performance. See our velvet types guide.

Faux leather. A coated fabric imitating leather, in three types: PVC, PU, and silicone. See our faux leather types guide.

Pattern repeat. The distance before a pattern returns to the same position, horizontal and vertical. Drives fabric wastage in cutting. See our pattern matching guide.

Cold crack. The temperature at which a coated fabric stiffens and cracks. Relevant to exterior and marine use. See our cold crack testing guide.

Quick answers

What does the Martindale rub count mean?
The Martindale rub count is the number of abrasion cycles a fabric withstands in the UK and European abrasion test before showing wear. The higher the number, the more durable the fabric. Contract-grade upholstery begins at 40,000 rubs, and heavy contract use calls for 100,000 or above. It is not comparable to the US Wyzenbeek double-rub figure.


What do the fabric cleaning codes W, S, WS, and X mean?
W means water-based cleaning is suitable. S means solvent-based dry cleaning only, and water can damage the fabric. WS means either water or solvent cleaning is suitable. X means vacuum or brush only, with no wet or solvent cleaning. The code is set for each fabric and should be matched to the cleaning regime of the environment before specifying.


Is velvet a type of fibre?
No. Velvet is a construction, a pile fabric, not a fibre. It can be woven from mohair, cotton, silk, linen, cashmere, or synthetic fibres, and the fibre determines the durability, fire rating, cleaning, and cost. Choosing velvet on appearance alone, without regard to fibre, is a common specification error.

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Contract Curtain Fabric Specification: A Designer’s Guide

Contract curtains are governed by a different fire standard from upholstery, and by a set of practical decisions, fullness, lining, drop, and light control, that determine both cost and performance. This guide covers what a designer needs to specify contract curtains correctly. For the upholstery fire standard, which is separate, see our BS 5852 Crib 5 guide.

The Curtain Fire Standard: BS 5867

Contract curtains are governed by BS 5867 Part 2, not by BS 5852 Crib 5, which applies to upholstery. The two are not interchangeable: a Crib 5 upholstery certificate does not qualify a fabric for contract curtain use, and a curtain certificate does not qualify a fabric for seating. BS 5867 Part 2 has two relevant types. Type B is the standard requirement for most contract environments, hotels, offices, public buildings. Type C adds a launderability pre-conditioning stage and applies where curtains are laundered repeatedly, principally healthcare cubicle curtains washed at 71 degrees Celsius. Specify the type by environment: Type B for general contract, Type C for healthcare and anywhere curtains are regularly laundered.

Most decorative curtain fabrics need topical FR treatment to meet BS 5867. Some inherently fire-resistant fabrics, notably Trevira CS, meet it without treatment. For which fibres can be treated and how, see our FR treatment and fibre compatibility guide and how FR treatment works guide. For the BS 5867 test method and the Type B and Type C wash-cycle detail, see our BS 5867 standard explained.

Light Control: Blackout, Dimout, and Sheer

Light control is specified separately from the face fabric and is usually delivered by the lining. Blackout blocks effectively all light, either through a face fabric with a blackout coating or, more commonly, a separate blackout lining. It is the standard for hotel bedrooms. Dimout reduces light substantially without eliminating it, suitable where full blackout is not required. A sheer or voile controls privacy and glare while admitting daylight, and is often layered with a heavier curtain or a separate blackout blind. Specify the light-control requirement by room: blackout for bedrooms, dimout or sheer-plus-blind for living and meeting spaces.

Fullness and Fabric Quantity

Curtain quantity is driven by fullness, the ratio of flat fabric width to finished curtain width, and by drop. A typical contract fullness is between 2 and 2.5 times the track width for a gathered or pencil-pleat heading, meaning a 3-metre track needs 6 to 7.5 metres of fabric width across the required drops. Wave and wave-style headings often use around 2.2 times. Sheers are frequently fuller, up to 3 times, to read well against the light. Drop is the finished length plus hem and heading allowances. For patterned fabric, add the pattern-repeat allowance on top: see our pattern matching guide for the method, and our fabric quantity guide for upholstery estimates.

Light Fastness for Curtains

Curtains at a window take direct and sustained sunlight, so light fastness matters as much as it does for upholstery in a bright room. A south or west-facing window fades a curtain at the fold lines before the body of the fabric shows change, producing an irregular striped effect that only full replacement corrects. For curtains in sun-exposed positions specify ISO 105-B02 grade 6 or above. For the full grading detail, see our light fastness and Blue Wool Scale guide. For the full specification library organised by environment, application, and performance need, see our fabric buying guide by purpose.

Quick answers

What fire standard applies to contract curtains?
Contract curtains are governed by BS 5867 Part 2, not BS 5852 Crib 5, which applies to upholstery. Type B is the standard requirement for most contract environments such as hotels and offices. Type C adds a launderability pre-conditioning stage and applies to curtains that are regularly laundered, principally healthcare cubicle curtains. A Crib 5 upholstery certificate does not qualify a fabric for curtain use. Most decorative curtain fabrics need topical FR treatment to meet BS 5867, though inherently fire-resistant fabrics such as Trevira CS meet it without treatment.


What is the difference between blackout and dimout curtains?
Blackout blocks effectively all light, delivered either by a face fabric with a blackout coating or, more commonly, a separate blackout lining, and is the standard for hotel bedrooms. Dimout reduces light substantially without eliminating it, suitable where full blackout is not required. Both are usually specified through the lining rather than the face fabric, so the decorative fabric can be chosen independently of the light-control requirement.


How much fabric do I need for contract curtains?
Curtain quantity depends on fullness and drop. A typical contract fullness is 2 to 2.5 times the track width for a gathered or pencil-pleat heading, so a 3-metre track needs 6 to 7.5 metres of fabric width across the required drops. Sheers are often fuller, up to 3 times. Add hem and heading allowances to the finished drop, and add the pattern-repeat allowance on top for patterned fabric.

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How Much Fabric to Upholster Furniture: Estimates by Type

Estimating how much fabric a piece of furniture needs is one of the most common calculations in a specification, and one of the easiest to get wrong. This guide gives working estimates by furniture type in metres, explains the variables that change them, and shows how to add the pattern-repeat allowance. For pattern matching and repeat calculation, see our pattern matching guide.

Estimates by Furniture Type

These are working estimates for plain fabric on a standard piece, based on a 140 cm wide fabric. They are starting points for budgeting and initial ordering, not a substitute for the upholsterer’s measured calculation on the specific frame.

PiecePlain fabric estimate (140 cm wide)
Dining chair, seat only0.5 to 0.75 m
Dining chair, seat and back1.5 to 2 m
Occasional or accent chair2.5 to 4 m
Armchair5 to 7 m
Wing chair6 to 8 m
Two-seat sofa10 to 14 m
Three-seat sofa14 to 18 m
Large or corner sofa18 to 25 m
Headboard, single2 to 3 m
Headboard, king3 to 4.5 m
Ottoman or footstool1.5 to 3 m

What Changes the Estimate

Several variables move the figure up from the base estimate, sometimes substantially. Fabric width is the first: the estimates above assume 140 cm. A narrower fabric, such as 130 cm, needs proportionally more length, and a very narrow fabric changes the cutting plan entirely. Pattern repeat is the second and largest: a patterned fabric needs extra length to align the repeat across panels, added on top of the plain estimate. A directional fabric or one with a pile that must run the same way on every panel, such as velvet, restricts how pieces can be cut and raises the quantity. Deep buttoning, pleating, valances, and contrast piping all add fabric. Loose covers need more than tight upholstery because of tuck-ins and hems.

Adding the Pattern Repeat

The estimates above are for plain fabric. For a patterned fabric, add the repeat allowance on top: one full vertical repeat per cut length for a straight match, one and a half vertical repeats per cut length for a half drop. On a large-scale repeat this can add a significant proportion to the plain figure. The full method, with worked examples, is in our pattern matching guide.

The Rule That Prevents Shortfalls

Always have the upholsterer confirm the measured quantity against the specific frame before the fabric is ordered, and order the full quantity in one dye lot. A job that runs short mid-way needs a fresh order from a potentially different dye lot, which risks a visible colour difference and a programme delay. For dye lot management on larger orders, see our lead times and custom colour matching guide. For the full specification library organised by environment, application, and performance need, see our fabric buying guide by purpose.

Quick answers

How much fabric do I need to reupholster a sofa?
As a working estimate on 140 cm wide plain fabric, allow 10 to 14 metres for a two-seat sofa, 14 to 18 metres for a three-seat sofa, and 18 to 25 metres for a large or corner sofa. These are starting points for budgeting. A patterned fabric needs more to align the repeat, and a directional or pile fabric such as velvet needs more because of cutting restrictions. Always have the upholsterer confirm the measured quantity against the specific frame before ordering.


How much fabric to upholster a dining chair?
For a drop-in or fixed seat only, allow 0.5 to 0.75 metres of 140 cm wide plain fabric per chair. For a chair with an upholstered seat and back, allow 1.5 to 2 metres. Add a pattern-repeat allowance for patterned fabric, and order all chairs in a set from a single dye lot to avoid colour variation between them.


Why does a patterned fabric need more than a plain one?
A patterned fabric must be cut so the repeat aligns across every panel and seam, which means each cut length starts at the same point in the repeat and the fabric between those points is waste. Add one full vertical repeat per cut length for a straight match and one and a half for a half drop. On a large-scale repeat this can add a substantial proportion to the plain estimate.

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Mohair Velvet vs Cotton Velvet: Which to Specify

Blue Velvet Chair

Mohair velvet and cotton velvet are the two natural-fibre velvets a UK designer chooses between most often. They look similar on a moodboard and perform very differently in a specification. This guide compares them across durability, fire rating, cleaning, appearance, and cost. For the full range of velvet fibres, see our velvet types guide.

The Core Difference

Mohair velvet has its pile woven from the hair of the Angora goat, a long, smooth, lustrous fibre of exceptional tensile strength. Cotton velvet has its pile woven from cotton, a shorter cellulose fibre. That fibre difference drives every specification distinction that follows: mohair is far more durable, carries an inherent fire rating, and has a directional sheen; cotton is softer in cost, matte in appearance, and needs treatment for contract fire compliance.

Comparison by Specification Measure

MeasureMohair velvetCotton velvet
FibreAngora goat hairCotton
Martindale rub count80,000 to 100,000 and above20,000 to 60,000 depending on construction
Fire ratingInherent BS 5852 Crib 5 in correctly certified ranges, no treatment neededNot inherent; topical FR treatment required for contract use
Cleaning codeS (solvent only)S or WS depending on range and treatment
AppearanceHigh lustre with directional sheen and depth of colourMatte to semi-matte, no directional sheen
SuitabilityHeavy contract and residential upholsteryDomestic upholstery, cushions, curtains, headboards
CostPremiumMid-range, plus FR treatment cost for contract use

Which to Specify

For heavy contract upholstery in hotels, restaurants, bars, and hospitality seating, mohair velvet is the sounder specification. It reaches 80,000 to 100,000 Martindale rubs, carries an inherent Crib 5 fire rating in correctly certified ranges without the cost or handle change of topical treatment, and its directional sheen gives the depth of colour associated with luxury upholstery. Confirm the inherent Crib 5 pass with an independent certificate for the specific range.

For domestic upholstery, cushions, curtains, and headboards where budget matters and use is lighter, cotton velvet is a sound mid-range choice. A well-constructed heavyweight cotton velvet reaches sufficient durability for general domestic and light contract use, but it needs topical FR treatment for any contract environment, which adds cost and can flatten the pile. Always confirm the specific Martindale figure, since cotton velvet quality varies widely.

For the fire treatment implications, see our Crib 5 guide. For durability figures, see our Martindale rub test guide. For the full specification library organised by environment, application, and performance need, see our fabric buying guide by purpose.

Quick answers

What is the difference between mohair velvet and cotton velvet?
Mohair velvet has its pile woven from Angora goat hair and reaches 80,000 to 100,000 Martindale rubs with an inherent Crib 5 fire rating in correctly certified ranges. Cotton velvet has its pile woven from cotton, reaches 20,000 to 60,000 Martindale rubs depending on construction, and needs topical FR treatment for contract use. Mohair has a directional sheen and depth of colour that cotton velvet does not replicate.


Is mohair velvet worth the extra cost over cotton velvet?
For heavy contract use, yes. Mohair velvet reaches far higher abrasion figures, carries an inherent Crib 5 fire rating without the cost and handle change of topical treatment, and lasts longer in daily multi-user settings. For lighter domestic use where budget matters, cotton velvet is a sound choice at lower cost, provided its Martindale figure suits the application and FR treatment is added where contract fire compliance is required.


Which velvet is more durable, mohair or cotton?
Mohair velvet is more durable. It reaches 80,000 to 100,000 Martindale rubs against cotton velvet’s typical 20,000 to 60,000, and its long, strong Angora goat fibre resists crushing and wear better than cotton’s shorter fibre. Mohair is the more reliable natural-fibre velvet for contract upholstery.

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PVC vs PU Leather: Which to Specify for Contract Upholstery

PVC and PU are the two synthetic leathers a UK specifier will meet most often, and they are not interchangeable. This guide compares them across the measures that decide a contract specification: abrasion, fire certification, cleaning, cold performance, and cost. For the wider comparison including silicone leather, see our faux leather types guide.

PVC and PU: The Core Difference

PVC (polyvinyl chloride) leather is built on a plasticised PVC layer over a textile backing. PU (polyurethane) leather is built on a polyurethane coating over a textile backing. The base polymer is the difference, and it drives almost every performance distinction that follows. PVC is the more robust and chemically resistant of the two. PU is softer, more breathable, and closer to the handle of real leather, but generally less durable over a long service life.

Comparison by Specification Measure

MeasurePVC leatherPU leather
Abrasion (Martindale)High; contract grades reach 100,000 and above, some over 200,000Moderate; typically lower than equivalent PVC, prone to surface peeling over time
HandleFirmer, can feel less naturalSofter, closer to real leather
BreathabilityLowHigher
Fire certificationReadily available with BS 5852 Crib 5Available but less commonly certified to Crib 5
CleaningWipe-clean, resistant to most cleaning agentsMore sensitive to solvents and prolonged moisture
Cold-crack performanceStandard PVC can stiffen and crack in cold; cold-resistant grades availableGenerally more flexible in cold, no plasticiser migration
LongevityLong service life in high-use contract settingsShorter; surface delamination is the common failure mode
CostMid-rangeMid-range, can be higher for premium grades

Which to Specify

For heavy contract upholstery in hotels, restaurants, bars, healthcare, and transport, PVC leather is usually the sounder specification. It reaches the highest abrasion figures, is readily certified to BS 5852 Crib 5, and wipes clean, which matters in high-turnover and infection-controlled settings. Confirm the cold-crack grade for any exterior or marine application, since standard PVC stiffens in cold.

For projects where handle and appearance are the priority and use is lighter, PU leather is the better choice. It feels closer to real leather and breathes better, which suits residential and boutique settings. The trade-off is service life: PU is more prone to surface peeling and delamination over years of heavy use, so it is less suited to the most demanding contract environments.

For cold-crack testing relevant to exterior and marine use, see our cold crack temperature testing guide. For the chemical safety and durability picture, see our faux leather sustainability guide. For the full specification library organised by environment, application, and performance need, see our fabric buying guide by purpose.

Quick answers

Is PVC or PU leather better for contract upholstery?
PVC leather is usually better for heavy contract upholstery. It reaches higher Martindale abrasion figures, is readily certified to BS 5852 Crib 5, and wipes clean, which suits hotels, healthcare, and transport. PU leather is better where handle and appearance matter more than service life, such as residential and boutique settings, but it is more prone to surface peeling over time.


What is the difference between PVC and PU leather?
PVC leather is built on a plasticised polyvinyl chloride layer and is more durable and chemically resistant. PU leather is built on a polyurethane coating and is softer, more breathable, and closer to the handle of real leather, but generally less durable. The base polymer is the difference and it drives their contrasting performance.


Does PU leather peel more than PVC?
PU leather is more prone to surface peeling and delamination over a long service life than PVC. This is the common failure mode for PU in heavy-use settings, which is why PVC is generally specified where durability over many years is the priority.

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Fabric Buying Guide by Purpose: Specification Guides for Interior Designers

Fabric Buying Guide by Purpose: Specification Guides for Interior Designers

This guide indexes the KOTHEA fabric specification library by purpose. It is organised three ways: by the environment a fabric is specified for, by the application it is used in, and by the performance requirement that governs the selection. Each entry links to a full guide covering the standards, test methods, and specification detail for that subject. Use it to move from a project requirement to the relevant specification guidance without reading the library in sequence.

By environment

The environment a fabric is specified for determines the combination of fire standard, durability, cleaning compatibility, and light fastness that applies. The guides below cover the principal contract and residential environments.

Hotel and hospitality

Martindale thresholds by room type, BS 7176 Medium Hazard fire certification, cleaning regime compatibility, and dye lot consistency across phased projects are covered in the hotel fabric specification guide. For the thermal and moisture behaviour of mohair in hospitality use, see the mohair thermal properties guide.

Healthcare

Disinfectant cleaning compatibility, BS 7176 fire certification, 100,000 Martindale durability, and infection control are covered in the healthcare fabric specification guide.

Marine and yacht

The IMO FTP Code, MCA MGN 580, and why BS 5852 Crib 5 is not interchangeable with IMO Part 8 are covered in the IMO marine fire standards guide.

Outdoor terraces and semi-outdoor spaces

Exposure mapping, solution-dyed acrylic, outdoor-rated faux leather, and light fastness by location are covered in the outdoor terrace fabric specification guide.

Poolside, spa, and chlorine-exposed areas

Why chlorine degrades fabric by a different mechanism than salt and UV, and what to specify for pool and spa surrounds, are covered in the poolside and chlorine-exposed fabric guide.

Acoustic and home cinema

How heavy velvet absorbs mid and high frequency sound and functions as an acoustic treatment is covered in the velvet sound absorption guide.

Contract versus residential

Why contract grade is defined by performance rather than by building type, and when a residential project needs a contract specification, are covered in the contract versus residential guide.

By application

The application a fabric is used in sets the abrasion, drape, and construction requirements independently of the environment.

Upholstery

The Martindale rub test, its classifications, and how it compares to the Wyzenbeek standard are covered in the Martindale rub test guide and the Wyzenbeek versus Martindale guide. Pilling resistance is covered in the pilling resistance guide, and the tactile character of the principal upholstery fibres in the fabric hand and tactile properties guide.

Curtains

Pattern repeat calculation and matching for curtains and upholstery are covered in the pattern matching guide. The applications where velvet is unsuitable, including several curtain and window conditions, are covered in the when not to use velvet guide.

Wall panels and headboards

BS EN 13501-1, BS 476 Part 7, the composite testing requirement for wall fabric, and the headboard fire standard ambiguity are covered in the wall panels and headboards guide and the BS 476 Part 7 guide.

By performance need

Where a single performance requirement governs the selection, the guides below address it directly.

Fire certification

BS 5852 Crib 5 is covered in the Crib 5 guide. How FR treatment works and which fibres can be treated are covered in the how FR treatment works guide and the FR treatment and fibres guide. Dye and FR treatment compatibility is covered in the dye types and FR treatment guide. The Building Safety Act 2022 documentation requirements are covered in the Building Safety Act guide.

Chlorine, UV, and salt resistance

Chlorine exposure is covered in the poolside and chlorine-exposed fabric guide. Light fastness and UV fading are covered in the light fastness and Blue Wool Scale guide. Cold crack temperature performance for coated fabrics in exterior and marine use is covered in the cold crack temperature testing guide.

Colour fastness and matching

Colour fastness and crocking are covered in the colour fastness and crocking guide. Colour naming, systems, and metamerism are covered in the colour naming and specification guide.

Chemical compliance and sustainability

UK REACH compliance is covered in the REACH compliance guide. Sustainability certifications are covered in the fabric sustainability certifications guide. Cashmere and mohair welfare certification is covered in the cashmere and mohair welfare certifications guide. Faux leather sustainability is covered in the faux leather sustainability guide.

Material selection

Velvet types compared across every specification dimension are covered in the velvet types guide, with mohair and cotton velvet compared directly in our mohair velvet vs cotton velvet guide. Faux leather types are compared in the faux leather types guide, with PVC and PU compared directly in our PVC vs PU leather guide.

Procurement and project planning

How much fabric a chair, sofa, or headboard needs is estimated in the how much fabric to upholster furniture guide. Contract curtains, covering the BS 5867 fire standard, light control, and fullness, are specified in the contract curtain fabric specification guide. How to write a complete fabric specification and what certificates to require is set out in the how to write a fabric specification guide. Definitions of the terms used across these guides are collected in the fabric specification glossary. Which fabric decision belongs at each project stage is covered in the RIBA Plan of Work fabric guide. Lead times, cuttings, dye lot reservation, and custom colour matching are covered in the lead times, cuttings and custom colour matching guide.

Quick answers

How do I choose the right fabric for a contract project?
Start from the governing requirement. Where a single environment sets the specification, such as a hotel, healthcare, marine, or poolside setting, the environment guide covers the full combination of fire, durability, cleaning, and light fastness standards that apply. Where a single performance requirement governs, such as fire certification or chlorine resistance, the relevant performance guide addresses it directly. Confirm the fire standard, Martindale threshold, cleaning code, and light fastness grade for the specific application before selecting a fabric.

What fire standard does my project need?
For most UK contract upholstery the standard is BS 7176 Medium Hazard, which incorporates BS 5852 Crib 5. Marine interiors follow the IMO FTP Code under MCA MGN 580, which is not interchangeable with Crib 5. Wall panels and headboards may fall under BS 476 Part 7 or BS EN 13501-1 depending on construction. The fire certification guides linked above cover each standard and when it applies.

How do I request samples of KOTHEA fabric?
Request cuttings of any KOTHEA fabric at KOTHEA.com/cuttings. Request cuttings early in the selection process, and where a scheme depends on several fabrics together, request cuttings of all of them so the combination can be assessed under the project’s lighting conditions before specification is finalised.

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Wyzenbeek vs Martindale: Which Abrasion Test Should You Specify?

Wyzenbeek vs Martindale: Which Abrasion Test Should You Specify?

Martindale: The standard used in the UK and Europe. Fabric is rubbed in a figure-of-eight motion against a worsted wool abradant. Results in rub counts. Contract minimum 30,000 rubs.
Wyzenbeek: The standard used in the United States. Fabric is rubbed back and forth in straight lines against a cotton duck canvas abradant. Results in double rubs. Contract minimum 15,000 double rubs.
Are they comparable? No. The two tests use different abradants, different motions, and different pass criteria. A Wyzenbeek double rub count cannot be converted to a Martindale rub count.
Which to specify: For UK and European projects, always specify Martindale. For US projects, specify Wyzenbeek. For international projects, request both where possible.

Interior designers working internationally, or sourcing fabric from American suppliers, regularly encounter both Martindale rub counts and Wyzenbeek double rub counts on specification sheets. The two figures look similar — both express abrasion resistance as a number — but they are produced by entirely different test methods and cannot be meaningfully compared. Specifying a Wyzenbeek result on a UK contract project, or a Martindale result on a US project, risks misaligned expectations with clients, contractors, and insurers. This guide explains how each test works, what the results mean, and how to specify correctly for UK and international projects.

The Martindale Test

The Martindale abrasion test is defined by ISO 12947 and BS EN ISO 12947. It is the standard abrasion test used across the UK, Europe, and most international markets outside the United States. When a fabric data sheet lists a rub count without specifying the test method, the default assumption in UK specification is Martindale.

The test works as follows. A circular sample of the fabric being tested is mounted face-down on a machine and rubbed against a standard abradant — a piece of worsted wool fabric — in a figure-of-eight motion that moves the sample across the abradant in all directions simultaneously. This multidirectional motion is designed to replicate the complex, non-linear abrasion that upholstery fabric experiences in real use. The machine counts each complete figure-of-eight cycle as one rub.

The test is run to one of several endpoints. The most common endpoint for upholstery fabrics is fabric breakdown — the point at which two threads have broken or a hole has appeared in the sample. Some test houses also assess and report pilling at intermediate intervals using a separate grading scale. The total rub count at breakdown is the Martindale rub count reported on the data sheet.

For a complete guide to Martindale thresholds by application and what the numbers mean in practice, see our Martindale rub test guide.

The Wyzenbeek Test

The Wyzenbeek abrasion test is defined by ASTM D4157, the American Society for Testing and Materials standard. It is the dominant abrasion test in the US contract furniture and upholstery market. UK designers sourcing fabric from American suppliers, or specifying for projects with US compliance requirements, will encounter Wyzenbeek results on data sheets.

The test works as follows. A rectangular sample of the fabric being tested is mounted on a machine and rubbed back and forth in straight lines — first in the warp direction, then in the weft direction — against a standard abradant. The standard abradant specified by ASTM D4157 is cotton duck canvas, a tightly woven plain-weave cotton fabric significantly more abrasive than the worsted wool used in Martindale. Each complete back-and-forth cycle counts as one double rub.

The Wyzenbeek test runs until the fabric shows noticeable wear or breakdown, and the double rub count at that point is reported. The linear back-and-forth motion differs fundamentally from the multidirectional figure-of-eight motion of Martindale, which is why the two tests produce results that cannot be directly compared.

Why the Results Cannot Be Compared

The most important point for a specifier to understand is that 50,000 Martindale rubs and 50,000 Wyzenbeek double rubs do not represent the same level of abrasion resistance. They are measurements from different instruments using different abradants, different motion patterns, and assessed against different pass criteria.

The cotton duck canvas abradant used in Wyzenbeek is more aggressive than the worsted wool abradant used in Martindale. All else being equal, a fabric tested to Wyzenbeek will reach its endpoint faster than the same fabric tested to Martindale, because the abradant is harsher. This means Wyzenbeek counts tend to be lower than Martindale counts on equivalent fabrics.

However, this relationship is not consistent across all fabric types. Different fibres and constructions respond differently to the two abradants and the two motion patterns. There is no reliable conversion factor between Wyzenbeek double rubs and Martindale rubs. Various informal conversion ratios circulate in the trade — most commonly the suggestion that one Wyzenbeek double rub equals approximately two Martindale rubs — but this ratio has no scientific basis and should not be relied upon for specification.

The only reliable way to compare two fabrics on a like-for-like basis is to ensure both have been tested to the same standard. When building a specification, always confirm which test method produced the figures on the data sheet.

UK and European Thresholds: Martindale

The following thresholds represent current UK and European contract specification practice for Martindale rub counts. For full detail on each threshold and the reasoning behind it, see our Martindale rub test guide.

Light domestic use: 15,000 rubs minimum. Heavy domestic use: 25,000 rubs minimum. Light contract: 30,000 rubs minimum. General contract — hotel lobbies, restaurant seating, office seating: 50,000 to 60,000 rubs. Heavy contract: 80,000 to 100,000 rubs. Severe contract: 100,000 rubs and above.

US Thresholds: Wyzenbeek

The following thresholds are used in the US contract market for Wyzenbeek double rubs. They are not equivalent to the Martindale thresholds above and should not be compared directly.

Residential use: 9,000 to 15,000 double rubs minimum. Light commercial: 15,000 double rubs minimum. Heavy commercial — hotels, restaurants, office seating: 30,000 to 50,000 double rubs. Severe commercial: 100,000 double rubs.

Which Test to Specify and When

For any project in the UK or continental Europe, always specify Martindale to ISO 12947. This is the expected standard, the one UK test houses use, and the one UK and European contract furniture manufacturers certify their fabrics against. If a fabric supplier provides only a Wyzenbeek result and cannot provide a Martindale result, request that the fabric be tested to Martindale before specifying it for a UK contract project.

For projects in the United States, specify Wyzenbeek to ASTM D4157. For international hospitality projects drawing from both European and American suppliers, request both test results where possible and compare within the same test method rather than across methods.

For yacht and marine projects, the fire standard takes precedence over abrasion performance. See our IMO marine fire standards guide.

Pilling: A Separate Test

Both Martindale and Wyzenbeek measure abrasion resistance — structural wear of the yarn. Neither measures pilling resistance, which is the formation of surface fibre balls through tangling of loose fibre ends. Pilling is assessed by a separate test, ISO 12945-2, also run on the Martindale machine but using a different abradant and a different assessment scale. A fabric with an excellent Martindale abrasion count may still pill badly in use. Always request both the Martindale abrasion result and the ISO 12945-2 pilling grade for contract upholstery specification. See our pilling resistance guide.

Quick answers

What is the difference between Martindale and Wyzenbeek?
Martindale rubs the fabric sample in a multidirectional figure-of-eight motion against a worsted wool abradant, counting each cycle as one rub. Wyzenbeek rubs the fabric back and forth in straight lines against a cotton duck canvas abradant, counting each back-and-forth cycle as one double rub. The abradants, motions, and pass criteria are different. The results cannot be directly compared.

Can I convert Wyzenbeek double rubs to Martindale rubs?
No reliable conversion factor exists. Informal ratios circulate in the trade but have no scientific basis and produce unreliable results across different fabric types. The only reliable approach is to test the same fabric to both standards.

What Martindale count should I specify for a hotel?
For hotel bedroom seating: 30,000 rubs minimum. For hotel restaurant and lobby seating: 50,000 to 60,000 rubs. For hotel bar and high-traffic areas: 80,000 to 100,000 rubs. See our hotel fabric specification guide for full detail.

Is Wyzenbeek used in the UK?
Wyzenbeek is not the standard abrasion test in the UK. Martindale to ISO 12947 is the expected test for UK and European contract specification. Wyzenbeek results may appear on data sheets from American suppliers. Always confirm which test standard produced the figures before using them in a UK specification.

What abradant does Martindale use?
The standard Martindale abradant for upholstery fabric testing is worsted wool fabric to ISO 12947-2. Results against different abradants are not directly comparable. Always confirm the abradant used when reviewing a Martindale certificate.

For Martindale thresholds by application, see our Martindale rub test guide. For pilling resistance, see our pilling resistance guide. For hotel specification, see our hotel fabric specification guide.

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Fabric Specification at Each RIBA Plan of Work Stage

Fabric Specification at Each RIBA Plan of Work Stage

The key decision points: Stage 2 establishes palette and mood. Stage 3 fixes performance requirements. Stage 4 produces the procurement specification. Stage 5 manages delivery and installation.
The most common error: Leaving detailed fabric specification to Stage 4 without having confirmed fire standard, Martindale requirements, and cleaning compatibility at Stage 3. Late changes at Stage 4 cause programme delay and cost increase.
For architects: The RIBA/BIID contract schedule of services explicitly covers FF&E specification. Understanding where fabric decisions sit in the Plan of Work helps coordinate the design team’s responsibilities.

The RIBA Plan of Work is the standard framework for organising building projects in the UK, used by architects, interior designers, contractors, and clients to structure the design and construction process from inception to completion. It divides a project into eight stages numbered 0 to 7. Fabric specification decisions are made at different stages with different levels of detail and different commercial consequences. Understanding which decisions belong at which stage prevents the most common fabric specification failures: late changes that cause cost overruns, incomplete fire certification documentation at handover, and procurement without confirmed dye lot availability.

This guide is relevant to both interior designers using the RIBA Plan of Work as a project framework and to architects who carry interior design services within their scope under the RIBA/BIID professional services contracts.

Stage 0: Strategic Definition

Stage 0 is the briefing stage, before the design team is formally appointed. Fabric specification is not a Stage 0 activity, but the strategic brief established at this stage determines the fabric specification constraints that will apply throughout the project.

Key questions that should be answered at Stage 0 and that directly affect later fabric decisions include: Is the building subject to specific fire safety regulations beyond standard Building Regulations — a hotel, a healthcare facility, a licensed premises? Will the interior be maintained by in-house staff or a facilities management contractor, and what are their cleaning capabilities and product preferences? What is the refurbishment cycle — how long must the interior last before planned replacement? Are there sustainability or environmental certification requirements for the project?

These answers will constrain the fabric specification options available at later stages. A project requiring BREEAM Excellent with Oeko-Tex or GOTS certification requirements for textiles should establish this at Stage 0, not discover it during Stage 4 procurement when the chosen fabric ranges may not hold the required certifications. For sustainability certification guidance, see our fabric sustainability certifications guide.

Stage 1: Preparation and Briefing

Stage 1 develops and finalises the project brief. For projects with significant interior design content, Stage 1 should establish the performance requirements that will govern fabric specification at later stages. This is not a stage for selecting specific fabrics, but it is the correct stage to establish the specification envelope within which fabric selection will occur.

Establish the fire standard applicable to each area of the building at Stage 1. For a hotel this means confirming the applicable BS 7176 hazard category for each room type. For a healthcare project it means confirming the HTM 05-03 requirements and the relevant BS 7176 hazard category. For guidance on fire standards, see our Crib 5 guide and hotel fabric specification guide.

Establish the Martindale rub count requirement for each area at Stage 1. The Martindale threshold is a function of the anticipated use intensity. See our Martindale rub test guide for threshold recommendations by room type.

Establish the cleaning regime requirements at Stage 1. Confirm with the client or facilities team what cleaning products will be used in each area, how frequently, and who will apply them. This information is essential for fabric cleaning code compatibility assessment at later stages.

Stage 2: Concept Design

Stage 2 is where the design concept is established and the spatial, material, and aesthetic language of the project is defined. Fabric decisions at Stage 2 are directional rather than specific. The concept palette might establish that lounge seating will be in a warm neutral mohair velvet, dining chairs in a deep blue contract textile, and bedroom headboards in a coordinating soft texture. These are design direction statements, not procurement specifications.

The Stage 2 concept design report should note — even at this directional level — which areas will require Crib 5 certified fabrics, which will require specific Martindale thresholds, and which will require specific cleaning code compatibility. This ensures the Stage 3 specification work begins with the performance envelope already established.

At Stage 2, initiate contact with key fabric suppliers to confirm that fabrics in the intended style and performance category are available within the project budget range. A concept that requires 100,000 Martindale mohair velvet in 40 colourways from a single supplier that does not offer that performance level will fail at procurement regardless of how well it is designed. Early supplier engagement at Stage 2 prevents this.

Stage 3: Spatial Coordination

Stage 3 is the most important stage for fabric specification. This is where specific fabrics are selected, performance criteria are confirmed against the Stage 1 brief, and the information required for cost planning and procurement is assembled. Errors or omissions at Stage 3 are the primary cause of fabric specification failures at Stages 4 and 5.

Confirm the specific fabric range, colourway, and width for every fabric in the scheme at Stage 3. Obtain the relevant technical data sheets from the supplier and confirm that each fabric meets the performance requirements established at Stage 1. For fire rating, obtain the test certificate — not just a supplier’s statement of compliance — and confirm that it covers the filling and construction being used in the specific project. For Martindale, confirm the rub count for the specific colourway ordered, not just the range average.

Obtain sample cuttings and confirm sample availability for mock-up testing if required. For large-scale hospitality or commercial projects, testing a mock-up panel or sample assembly to the required fire standard before committing to procurement is standard practice and eliminates certification risk at Stage 5.

Confirm lead times for every fabric at Stage 3 and identify any long-lead items. Specialist fabrics, bespoke colourways, and fabrics from European mills with minimum order requirements may have lead times of twelve to sixteen weeks or more. For lead times by fabric type, cuttings, dye lot reservation, and the custom colour matching process, see our lead times, cuttings and custom colour matching guide.

Produce a fabric schedule at Stage 3. The schedule should list every fabric in the scheme with its supplier reference, colourway, width, fire certification reference, Martindale count, cleaning code, lead time, and the locations in the building where it will be used.

Stage 4: Technical Design

Stage 4 converts the Stage 3 fabric schedule into procurement specifications — quantities, dye lot requirements, delivery programme, and coordination with the upholstery and curtain making workrooms.

Calculate fabric quantities at Stage 4 using confirmed cut sizes, seam allowances, and — critically — pattern repeat allowances for any patterned fabric in the scheme. See our pattern matching guide for the correct method of calculating pattern repeat allowances. Ordering without pattern repeat allowance is the single most common fabric quantity error and is discovered only when the workroom runs short.

Confirm dye lot availability with suppliers at Stage 4 before issuing purchase orders. For large quantities of a single colourway — a hotel project requiring 800 metres of a specific mohair velvet — confirm that the required quantity can be produced in a single dye lot. Dye lot variation between separately produced batches of the same colourway is visually detectable and will not be acceptable in a high-quality interior.

Coordinate the fabric delivery programme with the upholstery and curtain making workrooms at Stage 4. For upholstery, allow a minimum of four to six weeks between fabric delivery and installation for standard pieces. For complex bespoke upholstery, allow eight to twelve weeks. Build these lead times into the Stage 4 programme and work backward from the site installation date to establish the required fabric order date.

Stage 5: Manufacturing and Construction

Stage 5 is the construction and manufacturing stage. The designer’s role at Stage 5 is quality assurance and programme management rather than specification — the specification was established at Stages 3 and 4.

Inspect fabric on delivery to the workroom before cutting begins. Check the colourway against the approved sample under the lighting conditions of the finished room. For guidance on colour matching and metamerism, see our colour naming and specification guide. Check for any visible defects in the fabric surface. Check that the dye lot reference matches the order. Defects identified before cutting are the supplier’s responsibility to remedy.

Obtain all fire certificates and technical data sheets at Stage 5 and compile them into a building user guide or handover file. For commercial buildings, the Regulatory Reform (Fire Safety) Order 2005 requires the responsible person to be able to demonstrate that all furnishings comply with the applicable standards. The test certificates are the evidence of compliance and must be retained throughout the life of the installation.

Stage 6: Handover

Stage 6 is practical completion and handover to the client. The fabric-specific deliverables at Stage 6 are the fire certification documentation compiled at Stage 5, the fabric schedule updated to reflect the as-installed specification including any late changes, cleaning and care instructions for every fabric in the scheme, the supplier contact details for future reorders, and a maintenance schedule specifying when FR certification should be reviewed.

Quick answers

At what RIBA stage should I select specific fabrics?
Specific fabric selection — confirming the range, colourway, and technical data for each fabric — belongs at Stage 3. The design direction is established at Stage 2 and the procurement details are fixed at Stage 4, but Stage 3 is where the specific selection must be confirmed and tested against the performance requirements established at Stage 1. Leaving specific fabric selection to Stage 4 compresses the time available to identify and resolve problems with fire certification, Martindale counts, and lead times.

When should I order fabric for a large project?
Calculate the required order date by working backward from the site installation date. Allow for workroom production time — typically four to eight weeks for upholstery and curtains. Allow for fabric delivery from the supplier — typically two to four weeks for stock fabrics, up to sixteen weeks for made-to-order or specialist fabrics. Add the pattern repeat allowance calculation time. On a large hospitality project, the fabric order may need to be placed at or immediately after Stage 4 completion to meet a Stage 5 installation programme.

What documents should I hand over to the client at Stage 6?
Fire test certificates for all upholstered seating and curtains, cleaning and care instructions for each fabric in the scheme, the as-installed fabric schedule with supplier references and colourway codes for future reordering, and a note of any re-treatment or re-certification requirements during the life of the installation. The responsible person for the building requires the fire certificates to demonstrate compliance under the Regulatory Reform (Fire Safety) Order 2005.

For Building Safety Act 2022 documentation requirements across all RIBA stages, see our Building Safety Act and fabric specification guide.

For fire certification guidance, see our Crib 5 guide and hotel fabric specification guide. For Martindale thresholds by room type, see our Martindale rub test guide. For pattern repeat allowance calculation, see our pattern matching guide.

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Pattern Matching in Upholstery and Curtains: A Practical Guide for Interior Designers

Mohair, Cotton and Silk Velvet Textured Upholstery Patterned

Pattern Matching in Upholstery and Curtains: A Practical Guide for Interior Designers

The two pattern types: Straight match — each row of pattern repeats horizontally across the width at the same height. Half drop — each alternate width drops by half the vertical repeat before the pattern continues.
Extra fabric required: For a straight match, add one full vertical repeat per cut length. For a half drop, add one and a half vertical repeats per cut length.
The most expensive mistake: Ordering without accounting for pattern repeat on a large-scale repeat fabric. On a 64 cm vertical repeat, the wastage per cut length can exceed 50% of the usable fabric.
The practical rule: Always calculate yardage with the pattern repeat confirmed before ordering. Never estimate.

Pattern matching is one of the most practically consequential fabric skills in interior design and one of the most frequently handled incorrectly at the ordering stage. The error is almost always the same: the quantity of fabric ordered does not account for the waste inherent in aligning a patterned fabric across multiple widths and cut lengths. The result is fabric that runs short before the job is complete, requires a new order from a potentially different dye lot, and causes programme delay and additional cost. This guide explains how pattern repeats work, how to calculate the correct quantity, and how to specify pattern matching requirements clearly to upholsterers and curtain makers.

Understanding Pattern Repeats

A pattern repeat is the smallest unit of the pattern that, when tiled continuously, produces the complete fabric design. It is defined by two dimensions: the horizontal repeat (also called the width repeat or across repeat) and the vertical repeat (also called the length repeat or drop repeat).

The horizontal repeat determines how many times the pattern occurs across the width of the fabric. For a fabric 140 cm wide with a 35 cm horizontal repeat, the pattern repeats four times across the width. This is important for matching patterns across seams in upholstery and across drops in curtaining.

The vertical repeat determines the distance along the length of the fabric before the pattern returns to the same position. For a fabric with a 64 cm vertical repeat, a mark at a given point in the pattern will appear again 64 cm further along the length. This is the dimension that drives fabric wastage in cutting, because cut lengths must begin at the same point in the repeat to allow the pattern to match across widths.

Straight Match vs Half Drop

A straight match (also called a set match) is the simpler of the two main pattern arrangements. Every width of the fabric begins at the same point in the vertical repeat. When two widths are laid side by side, the pattern runs horizontally straight across the join without any vertical offset. Calculating the cut lengths for a straight match requires only one additional vertical repeat per cut length to account for the cutting waste.

A half drop match offsets each alternate width by half the vertical repeat. Width one begins at the top of the repeat. Width two begins at the halfway point. Width three returns to the top. When the widths are laid side by side, the pattern appears to step diagonally across the fabric. The half drop creates a more dynamic, less rigid pattern arrangement and is used for many large-scale geometric and floral repeats.

Calculating yardage for a half drop is more complex than for a straight match. In practice the effective usable repeat per cut length is the full vertical repeat plus half a repeat, not simply the full repeat — giving one and a half repeats per cut length as the minimum allowance.

Calculating Extra Fabric for Pattern Repeats

The standard industry method adds one full vertical repeat per cut length for a straight match, and one and a half vertical repeats per cut length for a half drop. These figures are the minimum safety allowances. For complex upholstery pieces with many separate panels, the wastage per panel compounds and may require a larger safety allowance.

A worked example for curtaining. The window requires four widths of fabric each 280 cm in length. The fabric has a 64 cm vertical repeat and a straight match. The base fabric required is four widths at 280 cm each, totalling 1,120 cm (11.2 metres). The pattern repeat allowance is one full repeat per cut length: four widths at 64 cm each, totalling 256 cm (2.56 metres). Total fabric required: 13.76 metres, rounded up to 14 metres. Ordering 11.2 metres would result in the job running approximately 3 metres short.

The same example with a half drop. The repeat allowance becomes one and a half repeats per cut length: four widths at 96 cm each, totalling 384 cm (3.84 metres). Total fabric required: 15.04 metres, rounded up to 16 metres. On a large scheme — a hotel with 40 windows of this specification — the difference between correct and incorrect pattern repeat calculation is significant in both cost and fabric quantity.

Pattern Matching in Upholstery

Pattern matching in upholstery is more complex than in curtaining because the pattern must be centred and aligned on each visible panel of the piece — seat, back, arms, and cushions — while the joins between panels must match. An upholsterer working with a patterned fabric must plan every cut from the fabric before cutting anything, to confirm that the pattern will align correctly across all panel joins and will be centred on each visible face.

Centring is the starting point. The dominant element of the pattern should be centred on the seat and on the back panel. This centring determines where the first cut of the pattern must be taken from on the fabric width. If the horizontal repeat does not divide equally into the seat width, some pattern will be lost at the sides. This is expected and acceptable. What is not acceptable is an unchecked centring that places a partial motif — half a flower head, half a diamond — at the centre of the seat.

Panel joining must be planned simultaneously with centring. If the seat panel requires the pattern to begin at a certain height, the back panel must begin at the same height in the repeat to allow the join to match at the seat-back junction. Planning all of these alignments together before cutting is the mark of an experienced upholsterer working with pattern fabric. The designer should confirm this planning process will be followed before the upholsterer cuts the fabric.

Large-Scale Repeats: Special Considerations

Large-scale pattern repeats — vertical repeats of 60 cm or above — require the most careful yardage calculation and pre-cut planning. At these scales the wastage per cut length can represent a significant proportion of the usable fabric. For a fabric with a 90 cm vertical repeat used on a chesterfield sofa requiring twenty separate panels, the pattern repeat allowance per panel may be the full 90 cm vertical repeat regardless of the panel height.

Large-scale repeats also demand that the upholsterer confirms the cut plan with the designer before cutting. Once the fabric is cut the pattern alignment is fixed. If a cut is wrong, the pattern in subsequent panels will be permanently misaligned and there may not be enough remaining fabric to recut.

Specifying Pattern Matching Requirements

When handing fabric to an upholsterer or curtain maker with a pattern repeat, specify the following in writing. The pattern type — straight match or half drop. The vertical repeat in centimetres. The horizontal repeat in centimetres. The centring requirement. The join requirement. And the instruction that a cut plan must be presented for approval before any cutting begins on pattern-critical pieces.

On complex pieces, consider requesting a paper pattern plan — a diagram showing which part of the pattern repeat each cut begins and ends at, with all panel joins annotated — before the fabric is handed over. This adds no significant time to the job while preventing the most common pattern matching failures.

Quick answers

How much extra fabric should I order for a patterned fabric?
Add one full vertical repeat per cut length for a straight match pattern. Add one and a half vertical repeats per cut length for a half drop pattern. For upholstery with multiple panels, apply the same allowance per panel rather than per complete piece. Always confirm the exact repeat dimensions from the fabric data sheet, not from the physical sample, before calculating.

What is the difference between a straight match and a half drop?
In a straight match, every width of the fabric begins at the same height in the pattern repeat. The pattern runs horizontally straight across joins. In a half drop, alternate widths are offset by half the vertical repeat. The pattern appears to step diagonally across the fabric. Half drops typically require more fabric and more complex cutting planning than straight matches of the same repeat size.

How do I centre a pattern on an upholstered piece?
Identify the dominant or focal element of the pattern. This element should be centred on the seat panel and the back panel. Lay the fabric across the seat frame or the cut panel template before cutting to confirm the centring visually. Once confirmed, use this as the reference point for all subsequent panel cuts to ensure joins align correctly.

Should I ask my upholsterer to produce a cut plan?
Yes, for any pattern-critical piece — a sofa or armchair with a large-scale repeat, a headboard with a central medallion, multiple matching pieces in a scheme. A cut plan shows which part of the repeat each panel is cut from and confirms that the pattern will align correctly across all joins before any fabric is cut. Make it a standard requirement for any patterned upholstery job.

For how much plain fabric a chair, sofa, or headboard needs before the pattern-repeat allowance is added, see our how much fabric to upholster furniture guide.

For fabric hand and handling properties, see our fabric hand and tactile properties guide. For fabric specification within project stages, see our RIBA Plan of Work fabric specification guide.

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