What “C.O.M.” Means — and How to Spec Fabric for a Custom Workroom

C.O.M. stands for “Customer’s Own Material” — fabric you, the designer, specify and supply, which the workroom then fabricates into drapery, upholstery, shades, or bedding. It’s the standard way trade work gets made: you control the textile, the workroom controls the craft. Getting the spec right the first time is what keeps a project on schedule and on budget.

If you specify window treatments or upholstery for clients, here’s how C.O.M. actually works — and where projects most often go sideways.

Why workrooms work in C.O.M.

A true trade workroom doesn’t sell fabric. It fabricates to your drawings, your finishes, and your goods. That’s the whole point: the pleat style, fullness, lining, and hardware are decisions you make, not defaults you inherit from a catalog. C.O.M. is simply the mechanism that lets you put the exact textile you sourced — at any price point, from any mill — into a piece built to your specification.

You’ll occasionally see C.O.L. (Customer’s Own Leather) for upholstery, measured in hides/square feet rather than yards. The principle is identical.

How much fabric to send: calculating yardage

Yardage is never a flat number — it depends on the piece and the goods. The variables that move it most:

• Fullness. Drapery is specified at a fullness ratio — commonly 2× to 2.5× the rod width. A 100-inch window at 2.5× fullness needs 250 inches of fabric width before hems and returns, which is what drives total yardage up fast.
• Width of goods. Most decorative fabric runs ~54 inches wide. Whether a panel can be cut in one width or has to be seamed changes the count.
• Pattern repeat. A large repeat means extra yardage so the pattern matches across panels, widths, and adjacent treatments. The bigger the repeat, the more you “lose” to alignment.
• Railroading. Running fabric sideways (railroaded) can eliminate seams on wide pieces like a sofa back or a wide valance — but only if the pattern allows it. Whether goods can be railroaded is one of the first things an experienced workroom checks.

The practical move: send the workroom the fabric details (width, repeat, content) and the drawings, and let them return a yardage requirement before you order. A good workroom would rather spend ten minutes on the math than watch you over- or under-order.

The CFA and approvals: don’t skip this step

A CFA — “Cutting for Approval” — is a swatch cut from the actual roll that will be used, sent for sign-off before anything is cut. It catches dye-lot shifts, the difference between a screen color and a real one, and flaws in the goods. On a high-end project, approving the CFA (and a strike-off on custom or printed goods) is cheap insurance against a very expensive remake.

How to send your goods to a workroom

A few habits that keep projects clean:

• Confirm yardage in writing first — order against the workroom’s requirement, not a guess.
• Ship to arrive before fabrication is scheduled, and label every bolt with the project, room, and piece.
• Flag direction and repeat — note nap, one-way patterns, and any railroading intent so nothing is cut the wrong way.
• Send extra for repeats and rematches — the workroom can advise how much.
• Inspect on arrival. A workroom that has been doing this for decades will catch a flaw or a short cut before it becomes your problem on site.

The mistakes that cost the most

In practice, the avoidable problems cluster: ordering yardage off a rough estimate instead of the workroom’s count; skipping the CFA and discovering a dye-lot shift after panels are sewn; missing a large repeat so patterns don’t align across a wall of windows; and assuming a fabric can be railroaded when it can’t. Each is a remake — time and material — and each is prevented by one conversation up front.

How a workroom quotes C.O.M. work

When you bring C.O.M. to a workroom, the quote covers labor, lining, hardware, and finishing — not the face fabric, which you’re supplying. The clearest workrooms tell you their yardage requirement, their lead time, and how they handle measuring and installation before you commit. If you ask how they’d handle an unusual return, a curved track, or a 14-foot drop and the answer is specific and immediate, you’re in good hands.

Working with Valley

Valley Studio is a trade workroom serving designers and architects in Los Angeles, New York, and San Francisco. We fabricate custom drapery, upholstery and reupholstery, shades, and furniture from your specified materials — by hand, since 1985 — and coordinate measuring and installation in each market.

Have C.O.M. on the way and a project to build? Start an inquiry and tell us what you’re working on.