Cracks in plaster - is it the cold winter?

[Glencky]

Hi there, I'm a newbie on here so be gentle with me! I had a quick look and can't find any similar questions, so I wonder if anyone can help me.

My husband and I bought a chapel conversion 6 months ago. The building is mid-1800s and was converted 10 years ago. It's Cotswold stone and although it's not listed, (not sure how it escaped that really TBH) it might as well be. Anyway, inside it's all very modern. I think in many places the people who converted it used very traditional methods and materials e.g. lime mortar for repointing outside etc. But inside some of the walls are concrete block and although some are drylined and I think (from the colour) at least some have lime plaster, others have normal modern plaster. The house is 'upside down' - bedrooms and bathrooms downstairs, and then a big open plan double-height room above.

In the last few weeks my husband and I have noticed that for every room downstairs, hairline cracks have appeared in the plaster. They're mostly in the line between the walls and the ceiling, all the way around but there are a few others e.g. around some of the windows (which are almost all stained glass). I'm not sure what's causing it but have 2 possible theories:

1) we've been using a dehumidifier because our bathroom gets a bit damp and we're paranoid about that after bad experiences in our previous house. But could we have dried the atmosphere out downstairs enough to cause such cracking? It's about 45% humidity at the moment...

2) something to do with the cold winter? I'm wondering if there's been a bit of building movement? No reason to believe there's any history of subsidence, and we had a full structural survey which certainly didn't highlight anything.

This plaster has been there since the place was converted so about 10 years. Am puzzled as to why, suddenly, the cracks.

All thoughts gratefully received!

 

[MdB]

Hi Glenky, welcome to the forum.

hairline cracks have appeared in the plaster.

I would die for hairline cracks. Can I swap yours for the ones I can get my fingers into?

Monitor your cracks if you wish but I really wouldn't worry about them too much. Modern construction houses have them too.

 

[Glencky]

Hiya, thanks for that! hahaha yes, I do know what you mean. I wouldn't say I'm exactly panicking about this as obviously it's not appearing the building's about to fall down... but... it's just a bit strange that they've all suddenly appeared now, that's all - I am very curious as to what has caused them. I might be totally off base with the dehumidifer but if it could be that we'll have to stop using it and find a different solution to our ensuite condensation issue (probably rip out the stained glass and fit double glazing, hahahaha NOT!) But if it's the cold weather then obviuosly nothig to do but fill and redecorate (which we were planning on doing anyway). And if something else well maybe I'd need to worry...

Although this house is already converted I've been thinking about trying to go on some DIY courses as I'd prefer to be able to understand more and do a bit more, although realistically probably most things we need to get done will require people who really understand their stuff. Unfortunately my dad died a few years ago so my usual solution to this kind of problem is no longer available to me...!

This forum's great, I can't believe I didn't go looking for it previously!

 

[JoceAndChris]

A big welcome to the forum - your building sounds so interesting! We'd love to see some pics of it, if you feel like sharing.

I wouldn't worry too much about the cracks. It's been a very hard winter and I've noticed a lot of extra cracking and crumbling here.

I was recently talking to a real expert in old buildings about the repair of my very cracked ceiling. (1- 3 inch diameter cracks!) I asked him if it would be likely to crack again after repair, he said yes, it's an old building and they just crack - if you don't like to see it put up lining paper.

I know what you mean about the dehumidifier - they can just pull out too much moisture, if that makes any sense. Have it on gently and in summer months open the windows wide and dry laundry outside if possible.

 

[Andrew Bodenham]

Glencky,

Hello, and welcome.

In short, the answer to your question is yes. The cracking you are seeing, particularly at wall - ceiling joins is probably due to the drying out (and subsequent contraction) of timber elements in your property, e.g. joists, drywall framing, studwork etc. The long cold spell earlier in the year will have had low humidity associated with it; those of us with heating were probably running it harder than usual at the same time. These are conditions which lead to timber shrinkage. Your dehumidifier will be having the same effect.

I have noticed the same phenomenon in my own house over the winter, and more pronounced than in previous years.

In most buildings this would be nothing to worry about. You can fill the cracks if liked with something like acrylic decorator's caulk which retains some elasticity - the cracks will tend to close up later in the year.

 

[Penners]

Welcome, Glencky!

As Andrew has said, there is a likelihood that your dehumidifier activity has contributed to the plaster cracks that you're seeing. But they don't sound like anything to worry about.

Over the past few months the ambient humidity in your house has probably been bouncing around all over the place, because of the combined effects of the dehumidifier and Mother Nature. This has caused the structure - particularly the wood - to move a fair bit, causing the cracks.

I've rarely seen a house that doesn't develop cracks between the walls and the ceiling That's why cornice mouldings were invented! The rest of your cracks are also around wooden elements, which is the clincher for the above explanation.

Andrew's suggestion of using decorator's caulk to fill the cracks might well work for you. I confess that I've never managed to get an invisible "mend" using that stuff on a flat surface. If you experience similar problems, then I should try using Polyfilla One Fill. It won't have the flexibility of acrylic caulk, but it is very easy to use and it's easy to make cracks completely disappear with it. Just be prepared for the fact that you may experience further cracking - or you may not.

Oh, and cut back on the dehumidifying a bit! Condensation is best reduced with a combination of warmth and ventilation. Has your bathroom got an extractor fan?

 

[CatherineB]

Welcome, Glencky!

I've rarely seen a house that doesn't develop cracks between the walls and the ceiling That's why cornice mouldings were invented!

Must tell DH; he's still moaning about the cracks at the join where we had a new wall put in, which keep reappearing... :mrgreen:

 

[robgil]

Hair in your plaster usually helps to prevent cracking.

 

[Penners]

Sorry - I've got none to spare.

 

[Glencky]

Folks, just logged on briefly this morning and so pleased by so many helpful replies! will come back later when I'm not supposed to be working (!) and reply properly. Will also post some pics when I get the chance! Am very glad I found this interesting, helpful and friendly forum.

 

[Penners]

will come back later when I'm not supposed to be working (!)

Don't worry about that, Glencky. All of us here are supposed to be working in some form or another - either officially "at work" or slaving away on our period properties. PPUK is what's generally known as a "displacement activity", with the added bonus that we can look as though we're doing research or seeking information.

 

[Balaphuel]

A common reason for hairline cracks in plasterwork where plasterboard is used is when the boards haven't been staggered when they were fitted. Also, many plasterer companies will use the largest sheets of plasterboard available as they tend to be the cheapest, but this too will cause cracking. The only way to limit cracking on board walls is to use smaller plasterboards. When I served my apprenticeship as a plasterer, we used very small rectangular plasterboards called lath boards. These were designed specifically for period buildings.

 

[Flyfisher]

PPUK is what's generally known as a "displacement activity", with the added bonus that we can look as though we're doing research or seeking information.

:lol: :lol: :lol:
Damn! Rumbled. Oh well, more tea? I've got some kitkats somewhere.

 

[Penners]

Be careful of the KitKats, FF. They can induce assessment. And assessment - sooner or later - leads to work.