Plaster Cracking Around Double Glazing

[RedOnRed]

We had new hardwood double glazed windows fitted last November and ever since i've had to keep going round them filling cracks that have developed in the plaster work and in the filler they used. Two of the frames have slight play which is enough to make the crack expand by a mil or two when they're moved with some degree of force.

The cracks don't run the entire length of the windows frame but are haphapzard and typically within 5mm of the frame.

They made good the first time and i've been round three times, which makes it four times by last May and it looks like they're ready for another flexible 10% filling/painting session.

The installer has just told me that he's never known anything like this in

22 years of being in the business and would like me to send him some photos before he commits himself to a visit, as he's not convinced it could be due to the windows...lol.

The house is constructed of solid plastered walls.

It's a problem we never had prior to the windows being fitted and is a complete nuisance of a job that I hadn't expected to have to do every couple of months.

Anyone else had any experience of this type of thing or a view of what might be causing it would be appreciated?

[Dave Liquorice]

The frames are moving, as you point out they are loose in the wall. IMHO a timber frame from shouldn't move at all under the sort of forces a hand can apply. Timber will also swell and contract with the seasons and humidity this can crack plaster but such movemment is small 1/2mm or so not several.

[Weatherlawyer]

Pictures would be helpful. Is it a bay window? How much of the frame closes the cavity and how much is actually sitting in brickwork?

What do you mean the house is made of plaster?

[RedOnRed]

Although the cracking is currently noticeable when you open the windows, it's not severe enough to appear in a digital photo.

It's not a bay window. The frame completely closes the cavity and they are sitting on the brickwork. The walls are solid and plastered. It's not timber framed and dry lined etc.

[Phil Anthropist]

Regarding the two frames that move, movement of the window frames could cause plaster to crack. The frames shouldn't move. Why didn't the fitter fix this when they made good the first time? Regarding cracking of plaster around frames that don't move, there are a number of causes of this, some of which can relate to the damage caused by the removal of old windows frames and fitting new ones, and some of which have nothing to do with your new windows. Without being able to see the property it is difficult to say. You could ask a builder/plasterer for an estimate of the cost of repair to see what they think is causing these cracks. It is a waste of time repeatedly filling and painting if the cause is not found and dealt with.

[Phil Anthropist]

When you tap the areas of plaster that are subject to cracking, with the blunt handle end of a screwdriver, does it sound hollow and different to the sound when tapping others areas of plaster away from the windows? If so, the plaster near the new frames has come loose from the underlying masonry and needs to be hacked off and repaired.

[RedOnRed]

Cheers, an independent quote is a good suggestion that I was considering myself.

Despite having a 10 year guarantee, the installers initial reaction is to think of every reason possible why his windows shouldn't be causing it and blame my property.

He has blamed the weather - but it was occuring during the winter too.

Dry lining and timber framed construction - I have neither.

Subsidence - no evidence of that.

At the moment there's slight play on at least two windows and a screw head that's sheard off. So i'll somehow get them in to deal with those and get them to inspect the cracking too.

[RedOnRed]

Yes, some of the plasterwork that is cracking does seem to be making a hollow noise when tapped, but i've also noticed that plasterwork that shows no evidence of cracking is also making the noise too.

[Phil Anthropist]

Double glazing guarantees are often limited as to what they cover. For example, the sealed units are often guaranteed against misting for 10 years, and the window and door handles are often guaranteed for 2 years. That may be all that is mentioned in their written guarantee. What does your guarantee cover? You are entitled to a satisfactory standard of work under the Sale of Goods Act, so that would include satisfactory installation of the window frames. This company's reluctance to turn you into a satisfied customer doesn't look promising. Trading Standards may help.

[Phil Anthropist]

Sounds like plenty of work for a plasterer.

[meow2222]

problem located, replastering time.

NT