Sat, 18 Apr 2026 17:23:14 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=33615#Comment_33615 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=33615#Comment_33615 Wed, 24 Sep 2008 19:46:06 +0100 Mike George Posted By: tonyMe too!

Chicken! The red mist has cleared now]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=33626#Comment_33626 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=33626#Comment_33626 Wed, 24 Sep 2008 22:14:36 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34640#Comment_34640 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34640#Comment_34640 Mon, 06 Oct 2008 17:51:32 +0100 arthur
Anwyay, back to walls:
Just how expensive is this adhesive that stingy use of it seems to cause such problems? I guess covering the whole surface of the plaster/insulation board (as you do with bathroom tiles) would be too expensive? But what about, as well as a continuous band around the perimeter, using several ribbons in a chessboard pattern over the board so any breaks in the ribbon only ventilate a cell and prevent major air movement. Would that be so expensive? Is it the labour that's expensive or the adhesive?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34650#Comment_34650 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34650#Comment_34650 Mon, 06 Oct 2008 18:26:57 +0100 Mike George
A general problem as I see it is that it is easier from a fixing point of view to just use blobs of thicker [texture] adhesive, which results in good air circulation in the voids - something which seems common, but which we don't want.

Covering the whole surface would be too hit and miss in my opinion. Using wet ribbons [only on flat surfaces] is a compromise which I find works well. I don't use this dot and dab on uneven walls anyway.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34763#Comment_34763 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34763#Comment_34763 Tue, 07 Oct 2008 21:00:03 +0100 arthur https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34784#Comment_34784 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34784#Comment_34784 Tue, 07 Oct 2008 23:07:52 +0100 Mike George https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34978#Comment_34978 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34978#Comment_34978 Thu, 09 Oct 2008 16:17:40 +0100 Mike George https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34981#Comment_34981 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34981#Comment_34981 Thu, 09 Oct 2008 16:30:19 +0100 Mike George ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34984#Comment_34984 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34984#Comment_34984 Thu, 09 Oct 2008 16:50:00 +0100 Paul in Montreal
Paul in Montreal.

p.s. no-one blobs and dobs over here - drywall is always screwed to either studs, joists or furring strips (even with masonry walls)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34987#Comment_34987 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34987#Comment_34987 Thu, 09 Oct 2008 16:59:26 +0100 Mike George https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34988#Comment_34988 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=34988#Comment_34988 Thu, 09 Oct 2008 16:59:59 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35010#Comment_35010 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35010#Comment_35010 Thu, 09 Oct 2008 20:54:44 +0100 Paul in Montreal Posted By: tonySo do how do your lot stop wind whistling arround behind the linings Paul?

Easy! Just make sure the external structure is airtight to begin with by using an air barrier!

Or, as is the case in our new house, the vapour barrier is foil-faced foam board that is installed on top of the studs (and taped at joints and sealed with acoustic sealant at change of plane) and then the furring strips are applied on top of that and then the drywall is screwed to the furring strips. No whistling wind at all.

In my on going renovation of an old brick house, the original plaster and lath has the lath nailed to battens which are nailed into wood strips that are embedded in the bricks at three different levels. In a couple of cases where the plaster and lath was removed (for various reasons) we put up foam board and then nailed furring strips through this into the nailing boards in the brickwork (after marking where these were. For the electrical outlets in a couple of cases where the wires were behind the foam board, we used "air tightness boxes" and taped and sealed these to the insulation to prevent any drafts. Drywall on top and everything is nice and tight. In a couple of other places we left the damaged plaster and lath in place, screwed foam board on top and then furring strips on top of that and did the same air tightness box trick for the electrical outlets (same thing in the ceilings too). We also spray foamed between the boards and the rim joist where necessary. All in all, no whistling behind any of the linings no matter how hard it blows outside.

Paul in Montreal.

p.s. I wasn't concerned about thermal mass either (in the old house) - there's so much wood in the house anyway that the temperature is very slow to respond to external changes. The 1.5 tonnes of wood we just laid on the upstairs floor has quite considerable thermal mass ;)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35088#Comment_35088 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35088#Comment_35088 Fri, 10 Oct 2008 19:24:19 +0100 arthur
In the brick house example, did you use a parge coat or just rely on the taped foam boards for airtightness? If the latter, don't you have moving air between the bricks and insulation which reduces performance? As Tony might say, doesn't it leave you with a tent of foam board within the brick structure and so not utilising the potential u-value of the brick layer itself?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35482#Comment_35482 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35482#Comment_35482 Wed, 15 Oct 2008 20:16:44 +0100 Paul in Montreal Posted By: arthurPaul, would be "it doesn't matter". Correct? You don't think air movement (convection) within the airtightness barrier will affect the insulation's performance?

In the brick house example, did you use a parge coat or just rely on the taped foam boards for airtightness? If the latter, don't you have moving air between the bricks and insulation which reduces performance? As Tony might say, doesn't it leave you with a tent of foam board within the brick structure and so not utilising the potential u-value of the brick layer itself?

I think preventing outside air from getting into the insulation in the first place is the most important aspect. Convection currents are driven by temperature difference so, in a solid foam situation, the air between the board and the cold wall will not have much of a driving force, neither will the air between the foam board and the plasterboard.

In my case, I didn't parge the brickwork (it wasn't practical to do this) and in some cases the brickwork was three courses thick. So there may be air between the brick and the foam board - which was carefully taped and foamed to make it as airtight as I could - but no real driving force to get that air to convect. As for the U-value of the brick, even three courses is not that much - equivalent to a 2x4 really (not even). Over here with the imperial R system, pine is R-1 per inch and a common 4" brick is about R-1 as well.

I also didn't add much insulation - just 12.5mm of polyisocyanurate - though this halves the heat loss of the wall but, hopefully, still allows enough heat through such that the brickwork won't get damaged by damp or frost.

And, all that said, air leakage is still around 38% of my total annual heat loss.

Paul in Montreal.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35485#Comment_35485 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=35485#Comment_35485 Wed, 15 Oct 2008 20:24:19 +0100 Mike George https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113158#Comment_113158 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113158#Comment_113158 Sat, 16 Jul 2011 13:38:45 +0100 spoonandfork 45mm eps backed plasterboard.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113171#Comment_113171 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113171#Comment_113171 Sat, 16 Jul 2011 17:33:52 +0100 tony
EWI is still better though.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113246#Comment_113246 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113246#Comment_113246 Mon, 18 Jul 2011 12:13:22 +0100 spoonandfork https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113263#Comment_113263 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113263#Comment_113263 Mon, 18 Jul 2011 16:30:54 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113267#Comment_113267 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113267#Comment_113267 Mon, 18 Jul 2011 17:33:46 +0100 spoonandfork https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113276#Comment_113276 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1070&Focus=113276#Comment_113276 Mon, 18 Jul 2011 18:34:35 +0100 tony