Skimming is the thin finishing coat of plaster that turns a rough, patched or tired wall into a flat surface ready for paint. In North Berwick we see everything from Victorian and Edwardian villas off Westgate to 1970s bungalows and newer builds out towards the Glen, and each type behaves differently under a trowel. Here is what actually matters before you book anyone in.
Skimming works when the background is sound. If your walls are structurally solid but covered in old wallpaper scars, patchy filler, textured coatings or hairline crazing, a 2 to 3mm skim over the whole wall will give you a flat, paintable finish for a fraction of the cost of replastering.
It is the wrong fix when the plaster underneath has failed. Tap along the wall with your knuckle: a hollow, drummy sound in an older North Berwick property usually means lath and plaster or lime render has lost its key and is sitting away from the wall. Skimming over that just adds weight to something already letting go, and it will crack again within a year or two.
Being a few hundred metres from the Firth of Forth changes things. Older sandstone and rubble-built homes near the harbour and along the seafront were designed to breathe, and wind-driven rain from the east gets into them. If those walls have previously been sealed with gypsum plaster and modern paint, moisture has nowhere to go and you get blown plaster and tide marks at skirting level.
On solid stone walls, a lime plaster system is often the honest answer rather than a gypsum skim, even though it costs more and takes longer to cure. On timber-framed and blockwork homes in the newer estates, standard board-and-skim is perfectly appropriate. Any plasterer worth using will tell you which category you are in before quoting.
Preparation is most of the job. Wallpaper comes off completely, loose material is scraped back, edges are cut out and filled, and the surface is treated with PVA or a bonding agent so it does not suck the moisture out of the plaster too fast. Plasterboard joints get scrimmed with tape. Skipping any of this is the usual cause of a finish that looks fine on day one and cracks by spring.
Two coats go on, are flattened, then trowelled up as the plaster sets. A single average bedroom wall might take a couple of hours; a full room including ceiling is typically a day for one plasterer, or a day and a half if there is heavy prep.
As a rough guide in East Lothian, skimming a single wall commonly lands somewhere around 150 to 300 pounds, and a full average bedroom of roughly 3.5 by 3.5 metres with ceiling in the region of 400 to 700 pounds. Access, ceiling height, the state of the existing walls and whether it is one room or a whole house all move that figure, so treat it as a starting point rather than a quote.
Fresh plaster turns from dark chocolate brown to a pale, even pink as it dries. Allow four to seven days in summer and up to two weeks or more in a cold, damp winter month before painting. Do not blast it with a heater to speed things up, as that causes cracking. When you do paint, the first coat should be a watered-down mist coat of contract matt emulsion, roughly three parts paint to one part water, otherwise the paint sits on the surface and peels away in sheets.