Yes, trim pieces around all the units to cover the join between the new units and old plaster. It's quite normal to do this rather than replastering up to the new units. From what i saw whilst the work was being carried out, the new units do butt up to the old plaster, apart from small areas where it was broken away when removing the old units.
Cavity insulation can fail and “slump” and I had a case recently where the surveyors on both sides were utterly baffled until they opened up the wall and discovered what had happened. It also happened right at the 25 year mark. They’re still arguing between themselves about whether the failure of the CWI caused cold bridging which in turn caused condensation or whether it acted as a conduit for external water to cross the wall. But, again, it’s puzzling that it’s all over, more or less all at the same time and so uniform.
The walls have been filled with cavity wall insulation(the small balls) for @6yrs, @3yrs before the widows were fitted.
It may not be your windows but the cavity wall insulation causing damp. Removing a brick from the wall near the window should allow you to examine the insulations condition. Back in the 80’s I bought a new build and had issues like, but not as severe, yours. It was cured by spraying the brick with a water seal product.
You will see a lot more of this. In older buildings, they were naturally leaky as hell due to older workmanship. On more modern buildings they are so much more airtight. This is compounded with new windows as these units are bloody well made these days. So whats happening is insufficient ventilation. However, there should have been some thermal bridging insulation and vapour proofing undertaken when installed. This may have been insufficient. But ventilation is usually the main culprit. Not saying thats the case here.
Nasher, I haven’t had time to read the whole thread. Just off to work, I am a window fitter, run my own business for 30 years, first point of call is your gutters and roofline, this looks like classic leaking from above and showing itself around the window line, check your roof felt hasn’t deteriorated and fell behind the fascia.
Sorry, I have not read all the way through, so will jump straight in with both feet! I worked in the industry for 35 years, the last five years as a professional surrveyor. Condensation can form, even with double glazing, on cold surfaces. Subject to moisture in the air, humidity. But.. Damp at the plaster line? I cannot see what the build type is on your property to be sure on this one but often the original timber windows will have a dpc, sometimes fastened (nailed) to the back of the old frames. Alternatively, there may have been a ‘cavity closer’ sometimes fastened to the back of the timber frames*. If either of these are removed with the old frame, which can happen easily when stripping out, you can end up with water ingress over time between internal and external wall. * damaged dpc or cavity closers should be re-instated. Sometimes cavity closers that fasten on to the old frames will mean the new windows are a tight fit. Sometimes ‘window fitters’ throw them away, rather than cut them down and retain them! All difficult to know from the photo. Is it all of the windows replaced, is it windows that get the weather more than others (1), are the windows in bedrooms(2)? 1. Could indicate dpc/cavity closer issues 2. A lot of moisture come from the people in the house simply breathing at night, holding breath is not an option
I think the key point here is the windows were fitted 3 years ago and the problem has only come to light, so what has changed ? or something he’s deteriorated.
I didnt look at all the photos, was on the way out…looking at the house/bungalow facing the property, I assume the same construction? Windows fitted under soffit? If so then definitely check out the condition of felt above. If rotten, short of gutter/facia, then that may well a be a big factor.
Many thanks Many thanks I really do appreciate everyone's comments and insight over this. It's had exactly the result I wanted, in that I've been directed to look at things I know nothing about, and I'm now far better equipped to deal with Anglia when they come back and look at it. I'm going to be pushing for them to completely remove one of the fitted units to examine the installation and inclusion or omission of a dpc or cavity closer. To answer these specifically. The windows affected are in a mixture of North and South facing rooms. One room effected is a bedroom used every night. One is my office that I do not use at night One is the spare room that is used very infrequently My lads bedroom used every night is affected, but far less than the other rooms.
I’ve just had another look at the photos and I reckon it’s penetrating dampness coming from behind the decor rather than condensation on the surface as a result of cold bridging. Is there a flat roof or defective guttering above the affected windows? Edit: I typed that before I saw Simmy and JBiker’s posts. It looks like you’ve got two very well qualified chaps on the team now, so hopefully you’ll crack the case soon.
Your dpm argument works for the sides of the window but not for the top of the window as there is obviously no vertical dpm there, if they have plastic cavity closers then these are impossible to remove during window fitting as they go across the cavity onto the inside brick and removal would take all the plaster off. Have you had any loft work done recently, placed something over your air brick in the loft, is your roofing felt tar based or fabric based, is your roof hipped or do you have gables, check your down pipes are not blocked , how’s the pointing on your gable tiles, I have seen this type of damp many times and the answer is nearly always caused by something above the window.
This probably isn’t the same issue as yours but I had a problem not long after moving into my house where there was an awful lot of damp in a particular window - and then there was a storm with driving rain coming from a different direction to the prevailing weather patterns. The damp became water pouring in from the top of the window recess. When I inspected the outside of the house I could see that all of the brickwork had been repointed above the window - extending a long way up the gable end - and extensive sealant work had gone on around the window. On the inside as I scraped off the now blown plaster I found evidence of previous repair and it was obvious that this had occurred before and various unsuccessful attempts had been made to fix the issue. After inspection and a little deductive reasoning I figured that water had no way of ingress around the window itself - so it must be coming down the inside of the cavity - hitting the top of the window lintel and then running through and soaking the plasterwork. As all of the brickwork had been repointed and there was nothing structurally wrong with the outer face of the brickwork I surmised that the cause was a combination of cavity wall insulation and corners cut on the original build. My choice was to either get a builder in to rip out the brickwork above the window and fix a proper waterproof channel above the window or prevent water getting through the brickwork in the first place. I gambled on the cheaper option first of course! I coated the whole of the gable end above the window with stormdry masonry waterproofing cream http://www.stormdry.com/ and since then I have had no issues regardless of driving rain direction or intensity of storm. It’s not cheap and needs to be applied properly but it does prevent water from penetrating the outer layer of brickwork - and by doing so is a bit of cheat to avoid having to deal with ripping out the window to fix issue with cavity closers, dpc, damp bridges etc. It worked for me so thought I would share.
Great example that, I really get it all the time, it’s always the window at fault but most often it’s something else, the window breaks the cavity , if there was no window then the water will continue down the cavity to below the damp corse, ideally above the window there should be a cavity tray and weep vents to direct water away from the lintel/ window. It can really be trying to find a needle in a haystack, it’s amazing how water tracks, a bit like trying to find a oil leak on a engine but on a greater scale.
I've seen exactly this, not saying it is the same reasons, but just the same results... The shortest distance from the outside to the inside is exactly where the damp is seen. We have a house that has been waiting for exterior cladding/rendering.. and when the wind blows the rain in a certain direction it causes the damp to make it diagonally through the blockwork. Personally I would be treating the outside of the house around the window area with a product such as this: https://www.amazon.co.uk/Sika-SKWATREP5-Water-Repelent-Kit/dp/B01JYXFRCY/ref=sr_1_60?keywords=sika+waterproofer&qid=1680624869&sprefix=sika+water,aps,427&sr=8-60 In fact, now that I think on.. we were getting the same issue in the bottom corners of the inside bedroom windows.. the water was coming through the stone window ledge...again shortest distance from outside to inside... Edit: PS: bloody 'ell that 5L container is actual size... (sorry cut n paste)
We’re on certain tasks only allowed to use Sika, we switched to 3M briefly but had a lot of issues with their product.
I can remember having so much respect for 3M as a schoolboy, but try not to go anywhere near the brand since the frying pan scandal, truly outrageous.
