skim cracking

15 Apr 2005
Reaction score
United Kingdom
In 2010 I had my lounge skimmed, and now there are long hairline cracks everywhere!!!

Is this normal? Why has it happened? The house is 100 years old, is it because of minor movement? Or the plaster drying out? The plaster skim coat was done over a very rough old plaster, so thought it'd do well in terms of "sticking" to the wall!
Sponsored Links
It is not unusual. Often the cracks will emanate from the corners of a door casing or window etc.

It can happen on new plasterboards.

Skimming should never be relied upon 100%.

In fact all plaster to some degree will be vulnerable to cracking, some more than others.

There are many factors which can contribute, but i will say that a brick built structure (internal skin) that has been wet plastered will probably fair the best.

The worst buildings are those built on clay out of lightweight aerated blocks that were laid wet.
Sponsored Links
Arf, arf!

What i will say is that skimming over walls is by no means a panacea for all things cracking, far from it.

If it was prone to cracking beforehand then it is likely to crack again.

However we have had the greatest success with over-skimming by preparing the walls or ceilings with a product called blue grit.

Expensive but good stuff. Worth the extra dollar.
I go to a lot of jobs where the plaster has cracks in it and it needs skimming, the trouble is if the plaster is cracked it can sometimes mean the browning has become "live" (lost suction to wall) and over skimming does not sollve the problem as the backing coat is loose and as skim is only 2- 3mm thick and will eventually crack.

I tend to scrim over all hairline cracks first, this helps ! but to solve the real problem you need to take all browning and plaster off wall ....... alot more expensive !

The trouble is you tell customers what need doing and they run a mile understandably, they then get joe blogs in to skim room at a fraction of cost and a year later the cracks re-appear.

I have done plenty of skimming jobs where really it need chopping off completley but I always warn customers that skimming is not guaranteed to recrack !
Funnily enough I thought the same thing. :mrgreen:

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links