Hi.

As the wind blows in terrible upstairs is it possible to block the upstairs floor void under the dormer stud wall with no worry of causing condensation problems or other problems??


I lifted some upstairs floorboards to find big gaps ( some places two courses of bricks) where the joists go through & the cavity stub wall meets the dormer stud wall?? (the stud wall is nearly all hidden in the roof void) I've read on other forums that it was there for ventilation purposes??

As a temporary fix I've wedged rockwool in the floor void between the joists & the downstairs ceiling/upstairs floorboards. This stops the draughts in most places but in some places I had problems wedging it in as the central heating pipes were in the way so you can still feel a slight draught if you put your hand there. Will this cause a problem when I have the carpet refitted??

What would be the best long term fix for this problem if there is one??

Thanks.

Thanks for your reply Tony & the info.

I've never done nothing like this before so am still confused to how it would be done?? Also whether it would be DIY job or a job for a expert (what trades person would do this job?)

As I said in my first post I've wedged pieces of Rockwool into the upstairs floor void up to the gap where the bricks are missing as a temporary measure. I've done the three bedrooms but not the bathroom (the winds still blowing in there) as I don't have access there yet. In the the three bedrooms it's much better but still not 100% draught proof as it was difficult where the central heating pipes are. Do you think it will still be ok to leave this Rockwool there until I get the job permanently done in the summer as I've not managed to do all the upstairs floor void & in places where I have done it you can still feel some draughts & I don't want this to cause problems with condensation etc. I'm having the carpets put down next week so if you don't recommend leaving it there I will take it out over the weekend.

When we come to do the job permanently looking at the photos would it be possible do think to remove the UPVC soffits & original soffit to gain access to the roof void. When in there add a vapour/air barrier to the outside part of the stud wall & down fixed to the outside of the cavity wall cutting it around the joists. Then when this is done & fixed add insulation to the outside of the vapour/air barrier?? (what insulation & vapour barrier would you recommend)

I should add at the moment where the bricks are missing from the top of the stub wall where it meets the stud wall in the roof void the cavity is open. It has been cavity wall insulated but will the draughts still get through into the floor void if it was done as above via the cavity??

As I said before I'm a complete novice when it comes to things like this so if my interpretation of what needs to be done is completely wrong would it be possible to give me a idiots guide of what to do please??

Thanks again.

Thanks again Tony for your reply & offer to come & help me. If I lived about 80 miles nearer to Reading I would take you up on your generous offer to save it from possibly being a DIY disaster.

From what you said I should be hopefully ok to leave the Rockwool that I've already wedged into the first floor floor voids in the three bedrooms up to the gaps. (just that someone from work put doubts in my head as they said it could cause problems?)

It would be in the the summer when I hopefully try to tackle the main problem of trying to do the roof void. As I've only looked into the floor void by lifting some floorboards to see the large gaps below the stud wall I'm still struggling to picture what will need to be done on the exterior in the roof void & it all seems double Dutch at the moment. I've tried to google it but have had no success yet.

Would it be possible to email you over the weekend a pencil drawing of what I could see in the floor void & then what I thinks in the roof void so you could correct me if I'm wrong?? Hopefully this way I could grasp it better what needs to be done.

Something that I've thought about today that I've not mentioned before is that the clad UPVC soffits don't have vent holes in so how's the roof currently vented??

Thanks for your help & advice again. As I mentioned before I'm a complete novice when it comes to things like this.

Thanks again for your advice & help Tony.

Just one final question if that's ok.

When looking at other threads on this & other boards it seems that a lot other people have had the same problem with these type of houses (draughts coming from the upstairs floor void). Why was it they were all built & left like this with large gaps where the joists go into the roof void?? Was the thinking then on houses like this it was best left with the floor void ventilated/open & now the thinking is that the floor void is best left unventilated/sealed??

Thanks again.

Hi

I'm hopefully going to finally try to start insulating the stub walls on the dormer windows & trying to seal the gap in the upstairs floor junction in the next few weeks by removing the eaves soffits (27" deep) & few rows of tiles.

I've had two lots of people round for quotes & they both said they would cut a big hole in the plasterboard below the window & then crawl into the roof void to do the work. They then said they would attach insulation onto the back of the plasterboard when it was fixed back in.

I recently cut a 3"x3" hole in the plasterboard stub wall below one of the windows to see what was actually in the roof void & as you would probably guess it went straight into the void with no insulation at all & like living in a plasterboard box. I also know that I'll only get a true picture when I remove the soffit. From what I can see the studs are 4" deep with what looks like a 2"x2" brace fitted diagonally across the studs. This leaves approx 1" gap from the plasterboard to the brace. I also should say that the brace doesn't go all the way to the top of the 4" vertical stud. There is also 4"x2" fitted in front of the 4" stud that I think supports the rafters. It looks like to try to get to top most of the 4" stud (under the window cill) would be difficult with this in the way & the slope of the roof??

I know I was previously advised to fit a vapour/airtightness barrier & solid board type insulation but I'm thinking this may be difficult to get a good fit with the diagonal brace being there?? Looking around on the 'net I found this http://thumbandhammer.com/projects/attic-3.html . I was wondering if I could do something like that using say 4" Rockwool between the studs & around the brace & then staple/tape Tyvek House Wrap on the outside of the studs?? Or would the solid board still be the best option?? (Having not ever used them before I'm not sure how easy it is to work with) I should also say that there are radiators fitted on all these Walls in the three bedrooms.

As for blocking the floor junction I did read on another website of someone getting heavy duty plastic bags & filling them with quilt insulation, taping the bags up, then wedging this in to the gap between the joists/wall & finally foaming around these. Would this be a good solution??

Thanks for looking.

Hi Tony.

Thanks again for your advice & informatoin.

Yes I think removing the plasterboard would be the best option but we were trying to do it another way as we had two bedrooms decorated/fitted wardrobes etc before finding out these Dormer style houses were poorly insulated upstairs. We were also going to leave the roof insulation until the roof needed doing & then get it hopefully better insulated from above.

The good news for us is though the two rooms that we've not yet touched upstairs are the bathroom & small bedroom that both have the sloping ceiling in. We were going to take the plasterboard off the sloping ceiling & put some solid board in there leaving a 2" gap at the top. Again though until I knock some plasterboard off I'm not sure what depth I'll get in there. As for the dormer cheeks I'm not sure what I'll find in those as they have external vertical tiles fitted as with the stud walls between the windows upstairs??

I know we will never get this house brilliantly insulated but we would like to get it done the best we can for the situation we're in.

Hi Tony.

Thanks again for your reply & info.

So I could get away with a 45mm ventilation gap in the sloping ceiling then which would allow me a bit thicker insulation?? What would be inside the dormer cheeks then if they are externally vertically tiled?? Would I need to leave a ventilation gap in these??

As you've done a house like this in Reading would like to do another one? ;-)

Thanks again.

The best way to stop the wind blowing through a dormer roof is to remove the roof tiles and cover the roof with a layer of plywood or OSB board, then put a layer or 2 of Polystyrene on top of the plywood and make it into a warm roof which doesn't need ventilating.

You could just fix a 70mm(ish) layer of insulation board between rafters then re-batten and tile, wouldn't think thermal bridging of rafters would be too excessive in that situation.

Hi Tony, Viking House, Davipon

Thanks for your advice & help.

I keep looking at it but I suppose I'm a bit of a scaredy cat at doing it myself.

I've looked on the net & also had a few people round to give me advice & prices to get it done.

A few things I've found & been told that I would like your advice on are:

1. What are your thoughts on the Icynene insulation product?? I've read mixed reports on it from this site & others.

2. Do I wait for the government backed green deal to start hopefully later this year?? With insulating houses hopefully it will a bit more than the normal loft & cavity wall insulation help.

3. I've had some tradesmen come round. The 1st suggested cutting a hole in the plasterboard on the front & back dwarf wall & then crawling into the roof void & insulating the wall with Rockwool. The 2nd suggested the main heat loss was through the flat uninsulated?? dormer roof. They suggested putting a warm deck on top of the original roof.

Thanks again for your help.

Try the warm front scheme they seem to do it for free!

Thanks all for the replies & advice.

I've been on the Warm Front web site but I don't think we would qualify for anything, but I'll give them a call tomorrow to just clarify this.

Just on the off chance could anyone recommend someone to do this type of work in the West Midlands/Worcestershire area.

Thanks again.

Hi Nick.

Thanks for your help & I'll have a look at it.

Thanks again.

probably open to the main roof and uninsulated. on the basis that they are small roofs you could fill them full of insulation from underneath, thermally line under the joists with a vapour barrier and call it done

do the flat roofs have puddles or need replacing?