Two different jobs
Skimming and replastering sound similar, and people often use the words for the same thing. They are not the same. A skim is a thin finishing coat applied over an existing surface that is basically sound. Replastering means taking the old plaster off, or the failed parts of it, and building the wall back up with new backing and finish coats, or sometimes boarding it instead.
Skimming is quicker, less messy and usually costs less. Replastering is more work, but it is the right answer when what is underneath has given up. The point of an assessment is to find out which one you are dealing with, rather than picking the cheaper option and hoping for the best.
What Luc looks for
The first check is whether the existing plaster is still bonded to the wall. Tapping along a wall will often show hollow-sounding areas where plaster has come away, usually called blown plaster. Small blown patches can be cut out and filled before a skim. Large areas, or walls where the plaster crumbles when touched, usually need taking back.
Cracks tell you something too. Fine crazing across a ceiling is common and often skims well. Wide cracks, cracks that keep coming back, or ceilings that have dropped or bowed may need more than a surface coat. Structural movement is not something a plasterer should diagnose, and if there is any sign of it, it is worth getting the right professional to look first.
Then there is the surface itself. Many layers of old paint, wallpaper residue, gloss on walls or heavy textures all change how a new skim will grip. Sometimes that means a bonding coat or extra preparation. Sometimes it means the old finish should come off.
Homes in Croydon and Streatham
Both areas have a wide spread of housing, including Victorian and Edwardian terraces, inter-war semis, mansion blocks, converted flats and modern developments. Older properties may have lath and plaster ceilings or lime-based walls, and newer ones are often plasterboard. But the age of a house does not decide the job. Plenty of older walls are perfectly sound, and plenty of newer ones have been damaged by leaks, poor repairs or hurried building work. Each room gets assessed on what is actually there.
Lime plaster needs a bit of thought. It behaves differently from modern gypsum, and patching it with the wrong material can cause problems later. Where it is relevant, Luc will say so and explain the options, including when a specialist would be the better call.
Textured ceilings and older coatings
Some ceilings and walls have textured coatings that were popular for decades. Older textured coatings can contain asbestos, and you cannot tell by looking. If there is a textured finish of unknown age, it should not be sanded, scraped or drilled until it has been tested by a suitably qualified person. Once the result is known, it may be possible to skim or board over it, or it may need specialist removal. Luc will not disturb it before then.
Why there are no fixed prices here
It would be easy to put a price per room on a page like this, but it would not be honest. Two rooms of the same size can need very different amounts of work. The price depends on condition, size, access, how much preparation is involved, and whether decorating follows. Photos are a good starting point, and a visit settles the details.
The same goes for timing. A skim on a sound wall and a replaster on a solid wall dry at different rates, and that affects when the room can be painted and used again. Luc will explain how that plays out for your room once he has seen it.
Getting your room looked at
If you are in Croydon, Streatham or nearby and are not sure whether your walls need a skim or something more, send a few daylight photos with your postcode to novacoat.plaster@gmail.com, or ring 07424 459772. Luc is based in Upper Norwood and will give you a plain view of what the room needs, and what it does not.