Is the wall ready for wallpaper?

Is the wall ready? It is ready when it is sound, dry, smooth enough for the material, evenly porous and free of anything that will come away later. Most walls fail at least one of those on first inspection, and the expensive paper does not fix any of them. A fine finish makes an uneven wall more noticeable, especially under side light or with a smooth, reflective material such as silk or a plain contract vinyl.

What does “sound” mean?

The surface has to hold. Old paint that is chalky or poorly bonded, filler sitting on dust, distemper, and the paper backing left from a previous hang will all let go under the pull of a drying wallcovering. The wall can look fine and still fail this test, which is why we look at the behaviour of the existing coating rather than its colour. A scratch test and a damp cloth tell you more than a photograph.

Is it dry?

Fresh plaster, new filler and recent repairs need time and the right conditions before they are covered. A calendar date is not proof: a moisture reading is. Where there is any history of damp, a cold patch or a stain that has spread, the cause is investigated before anything decorative goes near it. Our aftercare page explains why humidity and settling matter after the hang as well as before it.

Is it smooth enough for this material?

Smooth enough depends on the covering. A textured grasscloth forgives small undulations that a silk or a plain vinyl will show in raking light. Where the specification includes it, preparation means stripping old paper, sanding with dust extraction, and making good cracks and uneven surfaces before anything decorative goes up. Period walls can take days of filling and sanding before they are true. At Brown’s Hotel, the hours spent filling and priming decided everything that followed on wide-width printed papers.

What is lining paper for, and does this wall need it?

Lining paper is a plain paper hung before the finish. It does three jobs: it gives the finish one even, consistently absorbent surface instead of a patchwork of old paint, filler and plaster; it bridges hairline cracks and fine filler lines so they do not telegraph through; and it lets the joints of the finish sit away from anything beneath. It will not hold a coating that is letting go, cure damp, or straighten a wall that is out of true. Those are fixed first.

Whether it is needed is the maker’s call. de Gournay says “all walls should be lined with plain white 1000 or 1200 grade” lining paper, hung with the same adhesive as the panels, and that cross-lining “is not necessary so long as the vertical joints between the lining panels do not meet up” with the joints of the finish. Farrow & Ball recommends horizontal cross-lining “around 1200–1400 grade”, left for at least 12 hours before hanging. Zoffany recommends cross-lining too. Most contract vinyls are hung without a liner. Where lining is used, its joints never coincide with the joints of the finish, and it is dry before the top paper goes on.

Why prime or size, and with what?

A primer or size controls suction so the adhesive dries at the right rate, and on vinyl and contract products it is what lets the covering be stripped cleanly years later. The right primer and adhesive are a pairing chosen for the wallcovering and the substrate together, and the product’s instruction names them. de Gournay says new plaster and very absorbent surfaces “must be properly sized”, warns against oil-based primers that stay flexible, and says not to prime over its lining paper. Farrow & Ball asks for newly plastered walls to be “carefully sized”. Zoffany does not recommend thinning its paste “unless you’re sizing a porous wall”. Phillip Jeffries asks for “a hard, acrylic, pigmented, wall-protecting primer” made for wallcovering installation under its grasscloths (Grandview Grass instructions). Vescom, whose bespoke wallcovering we installed at Raffles London at The OWO, specifies its own Primer/Sealer, diluted or neat depending on the substrate, and its own adhesives on its adhesives and accessories page; that applies to Vescom wallcoverings, not to a residential paper or silk.

What none of them asks for is neat PVA brushed on as a universal sealer. It is the common shortcut, and it fails in a known way: it dries to a sealed, slick film that a water-based paste cannot soak into or grip, so the paper slides, dries slowly and can let go at the seams. Size or prime as the product’s instruction says. There is no single sealer or adhesive that solves every situation.

What needs a site inspection?

Photographs plan the job; they do not answer every question. Anything that cannot be confirmed until the old paper is off, a test area is tried or a moisture reading is taken should be recorded as uncertain in the scope, with an agreed way to authorise extra work. Typical cases: walls previously painted with gloss or a vinyl silk emulsion, walls with past water damage, new plaster that has not yet dried through, and walls where the specification calls for paper on joinery.

How does preparation affect the programme?

Preparation discovered late moves the installation date, and that is expensive when deliveries, decorators, joinery and occupancy have already been arranged. Ask for preparation to be described separately in the quotation, with what is included and what is subject to inspection; our guide to what changes the cost shows how. The survey is also a judgement on the wall: if it is not ready for the material specified, we say so before anyone orders the last drop.

When does this advice stop being reliable?

This is general guidance for domestic and hotel walls in reasonable condition. Damp, structural movement, lime plaster, historic fabric and any wall where the specification carries a fire or acoustic requirement need the product’s own instructions and, often, the specifier’s confirmation. The maker’s hanging instruction for the actual product takes precedence over everything on this page.