Plaster Repairs in Grangemouth: A Homeowner's Guide

Work out the cause before anyone mixes a bag

Tap the area gently with your knuckle. A solid, dull sound means the plaster is still stuck to the wall behind it. In that case you are probably looking at a surface crack. A hollow, drummy sound means the plaster has lost its grip, and no amount of filler will fix it. Anything drummy needs cutting out.

Then look at the pattern. Fine cracks spreading from the corners of doors and windows are usually movement and shrinkage, and only on the surface. A stain with a tide mark low down points to rising damp, or a damp proof course that has been bridged. Damp patches high on a gable wall or below a window more often mean rain getting in. The cause might be blocked gutters or worn pointing. These are common on the west and south walls that take the wind near the Forth.

What Grangemouth housing stock throws up

A lot of the town is housing from between the wars and just after. There are also 1950s and 1960s ex-council semis and terraces around Bowhouse, Newlands and Charing Cross. Two things come up again and again in homes of that age.

First, lath and plaster ceilings in the older houses. Your ceiling may have sagging areas, long cracks and a slight bounce. That means the plaster holding it to the wooden laths has snapped. A patch buys you a little time. The honest fix is to board over it, or take it down and put up new boards.

Second, artex and other textured coatings. If the texture went on before 2000, it may contain a small amount of asbestos. It should not be sanded or scraped dry. A test on a small sample does not cost much and is worth doing before any work starts.

Salt is the other thing worth knowing about. When plaster has been wet for a long time, salts move into it. They keep drawing water from the air, so the wall still looks damp even after the leak is fixed. That plaster has to come off down to the stone or brick. Then it is replaced with a suitable render and skim, not just painted over.

• Drummy or hollow when tapped: cut out and replace
• Hairline cracks only: fill, tape if needed, then skim
• Sagging, bouncy ceiling: likely lath and plaster failure
• Tide marks or salting: strip back, treat cause, re-render

Patch, skim or full re-plaster

A patch repair suits damage in one small spot, such as a knocked corner, a removed radiator or a small blown area. The join can sometimes show when light hits the wall from the side, especially through a shiny paint. So on a wall that is easy to see, a patch is often best followed by a skim of the whole wall.

A skim coat over sound plaster gives you one flat, smooth surface. It is the usual answer when the wall is basically fine but tired, patched or marked by old wallpaper. A full re-plaster means stripping the wall back and starting again. It is for walls that are badly blown or damaged by salts.

Plan around the timings. Skimming one room usually takes one to two days. The plaster then needs 7 to 10 days to dry before painting, and longer in a cold room or in winter. Fresh plaster needs a watered-down mist coat first. Never put a vinyl emulsion straight on, because it will peel.

What affects the cost

Every repair is priced on access, ceiling height, how much preparation is needed and whether damp work is involved. A small patch is a quick job. A lath and plaster ceiling that has to come down and be reboarded is a much bigger one. We look at the job for free and give you one fixed price before any work starts.

Be wary of any quote given without someone seeing the wall. Be even more wary of one that says nothing about fixing the cause of the damp. A cheap skim over a live leak means paying twice.

Common questions

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