Type I, II and III, and why it matters
ASTM F793 sorts commercial wallcovering into durability categories, driven mainly by weight per square yard plus abrasion, tear and adhesion performance. The categories are not grades of quality. They are fitness for a location.
| Type | Weight (oz/sq yd) | Where it belongs |
|---|---|---|
| Type I | ~7–13 | Light duty. Private offices, guest rooms, low-traffic walls. |
| Type II | ~13–22 | Medium duty. The commercial norm: corridors, lobbies, lifts, public areas. |
| Type III | 22+ | Heavy duty. Where impact is expected. |
Specifying Type I where Type II belongs is the most common durability mistake in the trade. It does not fail immediately. It scuffs along a corridor at cart height and opens at the seams a year or two in, by which point everyone has forgotten the specification decision that caused it.
Fire rating
Most commercial interiors require Class A, which under ASTM E84 means a flame spread index of 25 or less and smoke developed of 450 or less. Code generally requires Class A in exits and exit access corridors, with some relief in smaller rooms depending on occupancy and sprinklering.
The rating belongs to the assembly, not the roll. Adhesive and substrate are part of the tested system. Confirm the requirement against the project specification and the authority having jurisdiction rather than reading it off a product data sheet and assuming.
What the substrate has to be
A heavy textured Type II vinyl will cover a competent Level 4 finish. A light, thin, tightly woven or high-sheen material will not, and wants Level 5. The failure is joint banding and fastener shadowing telegraphing through the face, and it typically only appears once the wall is lit, which is after the goods are hung.
When the specification is silent and the goods are light or reflective, we either price Level 5 preparation or state the assumption in the bid. We do not discover it on the wall.
Hanging over existing material
It can be done. It is usually a bad idea. New adhesive rewets old adhesive, so the existing material can release and bring the new goods down with it. Existing seams telegraph. And if what is already there is vinyl, you have just added a second vapour-impermeable layer to the wall.
Removal, substrate repair, skim coat and the correct primer is the durable path. The exception is a sound, well-adhered, tightly seamed lightweight substrate with a liner over it, and that is a call to make on site, not from a drawing.
The mould question, answered properly
Vinyl is a vapour retarder. In a hot humid climate with an air-conditioned interior, vapour drives from outside toward the cool inside. At the back of a vinyl wallcovering on the inside face of an exterior wall it has nowhere to go, so it condenses on the gypsum and feeds mould.
This is an assembly problem, not a product defect, and it is why permeable goods or a rethought vapour strategy get specified on exterior walls in those climates. On interior partitions in a dry climate it is a non-issue. Anyone who tells you vinyl wallcovering simply causes mould has skipped the part that actually determines whether it does.
What we hang
- Type I, II and III vinyl. The commercial workhorse, in every weight.
- Textiles, silks, sisal and grasscloth. Natural goods with railroading, shading and panel-sequencing considerations that vinyl does not have.
- Acoustical wall wraps. Site-built track and wrap systems and prefabricated panels, where the finish quality lives in track layout, corner detail and fabric tension.
- Digital murals. Panel-sequenced, drop-matched, with the registration checked before anything is cut.
- Removal and preparation. Strip, repair, skim coat and prime, which on remodel work is most of the actual labour.
What drives the price
Material and labour move independently. A standard Type II is a modest material cost; silks, acoustical wraps and custom murals can be many times that. On labour, the drivers are substrate condition, whether existing material has to come off, pattern repeat and match, wall height and access, and whether the building is occupied while we work.
A straight-run corridor in new construction and a pattern-matched mural in a live lobby are not the same job at the same rate. A square foot number quoted without the drawings is close to meaningless, and it is usually revised later.
Getting a number
Send the architectural set, the finish schedule and the finish legend, plus any addenda. Tell us the bid due date, the anticipated start, and whether the building will be occupied. Lump sum with a scope letter, alternates priced separately.