Plaster popping over screw heads

[chilluk]

Our loft conversion has been plastered about 4 / 5 weeks now and so I am painting it all.

Before the mist coat I noticed a handful of popped screw heads here and there and so dug out the plaster, filled with polyfilla and got on - I assumed this was normal to get a few go.

Over the last week or so another 10 or more have popped in various places, normally in corners between walls or between wall / celing.

Is this normal - I mean I guess so far I've scraped out and filled 20 - 30 in all, but how long would you expect this to go on for? Or shouldn't it be happening at all? I expected the structure was settling a little and wasn't worried at first, but I see a new one or two every time I go up there it seems!

I want to get on with top coating all the walls and ceilings but not if I'm going to get loads of holes appear.

If normal or not what is the best method / materials to use to fix permanently? Should I be moaning at the builder?

Cheers.

Chris

 

[Richard C]

Usually caused by either differential movement or if damp timber was used for the stud work; or both. If it’s damp stud timber, it will eventually stop but if you’ve got movement, it could remain a recurring problem. Most probably causes in this case would be insufficient stud size, poor construction or undersized roof (floor) joists; did you upgrade them as part of the conversion?

 

[chilluk]

Yep floor joists etc all done as per structural calcs -I saw them going in and they were substantial, same with the steels.

Timer prob was damp - the work was going on throughout firstly the wettest, and then the coldest weather we've had for years. So if it's this, when it's dried out it should stop happening hopefully?

How about the remdey - should I "prime" the screw heads first? Obviously make sure they are tight. Is polyfilla OK - I don't want to use caulk because I find it always shrinks back a bit and is unsandable of course.

 

[Richard C]

Damp stud & constructional timber may well be your problem; not particularly good practice but it should stop once it’s thoroughly dried out. It may take another 6 months or so this time of year but don’t be tempted to hurry things along with more heat up there than you need for normal use, it will only make things worse. You may get more screws popping & even some significant cracking, especially at the joins, depending on how damp & swollen the timber was. Use a screw driver to nip the drywall screws up if needs be but you don’t need to prime the screw heads before filling. I would be inclined to use Easyfill;
http://www.british-gypsum.com/produ...ries/gyproc_accessories/gyproc_easi-fill.aspx

but a sandable filler will do; don’t use caulk.