Upholstered seating is where most custom-furniture projects either shine or stumble. The gap is rarely the frame — it is the foam, the fabric, and the fire-safety paperwork. For European and US importers, getting the upholstery specification right up front is the difference between a product that passes customs and one that is recalled. This guide walks through what to specify before you quote.
1. Foam density and support
Foam is measured in two numbers buyers should learn: density (kg/m³) and ILD (Indentation Load Deflection, how hard it feels). A seat that sees daily use should sit around 30–45 kg/m³ HR (high-resilience) foam; back cushions can be lighter. Density is what resists collapse over years, not the initial softness. State both numbers in the RFQ and ask for a mill sample, because the same chair can feel wildly different on 22 kg/m³ versus 35 kg/m³ foam.
2. COM and COL: who supplies the cover
COM (Customer's Own Material) and COL (Customer's Own Leather) mean the buyer sends the cover fabric or leather to the factory. This is common for designers matching a scheme. Two rules matter: the material must be upholstery-grade (abrasion rating, usually 30,000+ Martindale rubs for contract use), and the buyer must supply enough with a cutting allowance (typically 15–20%) for pattern matching and mistakes. If the factory supplies the fabric, ask for the FR (flame-retardant) treatment certificate up front.
3. Fire-safety compliance by market
This is the part importers underestimate. The rules differ by destination:
United States (CAL 117): California Technical Bulletin 117 is the de-facto US standard for residential upholstery smolder resistance. Many states adopt it. Spec it for any US-bound seating.
United Kingdom (BS 5852): The UK requires ignition-source testing (cigarette and match equivalents) on both cover and interliner. A composite test report is needed.
EU (EN 1021): EN 1021-1 (cigarette) and EN 1021-2 (match) govern smolder and flame resistance across the EU, backed by the General Product Safety Regulation.
Note that the old California TB 133 (full-scale institutional) applies to hospitality and contract installations, not homes. Name the exact standard in your PO so the factory treats foam and interliner accordingly.
4. Interliners and FR treatment
When a decorative fabric is not inherently flame-retardant, a barrier interliner (or FR back-coating) sits between foam and cover to meet the standard. Specify whether the FR treatment is chemical (and low-VOC, to satisfy REACH) or a physical barrier cloth. Keep the test lab report — customs and retailers will ask for it.
How Vashone builds upholstery
At Vashone, every upholstered program starts with a foam-and-fabric sign-off: we provide a density/ILD spec, source COM/COL or our own FR-certified covers, and build a prototype that we flame-test to the target standard before mass production. Our Houjie (Dongguan) workshop handles sofas, lounge chairs and banquettes for EU and US clients, with full EN 1021 / CAL 117 documentation on file. Send us your cover and we will engineer the seating to pass on the first try.