lizzie Posted August 20, 2017 Share Posted August 20, 2017 Hi all be grateful for some help on a worrying (to me) scenario that has developed on our mbc frame in the last few days. Lots of rain and the building is not watertight, the roof boards leak like a sieve even with a membrane. We are going as fast as we can with trusses to get it ready for single ply membrane finish. The mbc roof boarding is really wet in places and so are the joists underneath. The walls are wet but too a lesser degree. We have puddles all over the place inside with water collection in dips in the slab so its a very warm moist atmosphere due to window openings being covered in heavy duty polythene awaiting window arrival. Yesteday I notice what appears to be black mould spots on the roof boards and the joists. Can anyone tell me if this is an issue both for construction and health. I have a serious health issue and cannot tolerate any mould whatsoever, part of the reason for the build was to have a clean air healthy house and now I have seen the mould I am very worried and in something of a panic. Pics attached. All input gratefully received. Many thanks Liz Link to comment Share on other sites More sharing options...
dpmiller Posted August 20, 2017 Share Posted August 20, 2017 Is there a problem with the picture (stitched?), or do the last three posijoists in the bottom pic have a break in them towards the middle of the image? Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 2 minutes ago, dpmiller said: Is there a problem with the picture (stitched?), or do the last three posijoists in the bottom pic have a break in them towards the middle of the image? I think it must be something with the photo I dont recall seeing anything like that on site. Well spotted! Link to comment Share on other sites More sharing options...
Barney12 Posted August 20, 2017 Share Posted August 20, 2017 Hi Liz Don't panic. Our MBC frame got drenched for weeks during and after installation, it's rains up here like knowhere ive ever seen (well apart from the Western Isles of Scotland!). Pools of water everywhere (our slab too is far from level). As you say the roofing membrane doesn't keep the water out. Flooring was completely soaked. It will dry dry out relatively quickly once you're watertigh and you're problably going to need a mild bleach solution to wash away that surface mould. The only damage we have as a result of the water is all the floorboard edges have swelled. When the time comes I'm going to have to hit the floor deck with 40g on a belt sander but when I think just how drenched it was that's not any great hardship. Oh oh and if you read through the archives you'll see that I didn't want to build in the winter to stop this very issue. British summertime!! yeh right!! 1 Link to comment Share on other sites More sharing options...
Barney12 Posted August 20, 2017 Share Posted August 20, 2017 P.S. I recall you're in Devon too? Drop me a PM if you want to see a now dry MBC frame. The guys are here at the moment doing all the airtightness work. Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 1 minute ago, Barney12 said: Hi Liz Don't panic. Our MBC frame got drenched for weeks during and after installation, it's rains up here like knowhere ive ever seen (well apart from the Western Isles of Scotland!). Pools of water everywhere (our slab too is far from level). As you say the roofing membrane doesn't keep the water out. Flooring was completely soaked. It will dry dry out relatively quickly once you're watertigh and you're problably going to need a mild bleach solution to wash away that surface mould. The only damage we have as a result of the water is all the floorboard edges have swelled. When the time comes I'm going to have to hit the floor deck with 40g on a belt sander but when I think just how drenched it was that's not any great hardship. Oh oh and if you read through the archives you'll see that I didn't want to build in the winter to stop this very issue. British summertime!! yeh right!! Thank you so much that is a huge comfort! We too waited for the great 'British Summer' would have been better off starting in Feb not June! Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 Just now, Barney12 said: P.S. I recall you're in Devon too? Drop me a PM if you want to see a now dry MBC frame. The guys are here at the moment doing all the airtightness work. I'm in the Midlands near Stratford upon Avon. Would love to see will pm thank you. Link to comment Share on other sites More sharing options...
ProDave Posted August 20, 2017 Share Posted August 20, 2017 I wonder what membrane they use? Protect VP400 plus kept out house dry all bar a few drips for months before I got the roof tiled. 1 Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 4 minutes ago, ProDave said: I wonder what membrane they use? Protect VP400 plus kept out house dry all bar a few drips for months before I got the roof tiled. god knows what it was, mbc put it on I have no idea just a sort of pale grey colour Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 28 minutes ago, ProDave said: I wonder what membrane they use? Protect VP400 plus kept out house dry all bar a few drips for months before I got the roof tiled. found it on a pic. It was ' Amatop Aero plus'if that means anything Link to comment Share on other sites More sharing options...
Mr Punter Posted August 20, 2017 Share Posted August 20, 2017 It is not ideal but will not be an issue as it is short term. Sweep out any big puddles on the floors. Try to get the roof on ASAP. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted August 20, 2017 Share Posted August 20, 2017 Our MBC frame also got thoroughly drenched, as we had a day of very heavy rain whilst the frame went up. No significant impact, other than some discolouration and a little bit of minor swelling of the OSB flooring at the joints when it dried out. The latter was easily sanded out, and there was no long term damage. I think it's just one of those hassles of trying to build in the UK - the chances are it will rain a lot at some point before you get the roof on............ Link to comment Share on other sites More sharing options...
PeterW Posted August 20, 2017 Share Posted August 20, 2017 It's not just TF that suffers. We have Egger Protect and it was exposed for nearly 4 months - I had glued the joints and it basically became a swimming pool in some places ..! It held water well, and we would regularly sweep bucket loads off it. In one or two places there are slight swells in the joints. On the other hand, the old ordinary chipboard was exposed for 3 weeks and it turned to mush ..! We took it out with a sledghammer through it and it took longer to pull the nails up than it did to remove the board ...! Link to comment Share on other sites More sharing options...
lizzie Posted August 20, 2017 Author Share Posted August 20, 2017 Thank you all. Your advice is very much appreciated. We have torrential rain here again and I don't even want to think what it will be like on site tomorrow. We are on solid clay and water does not go very far! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now