Tue, 19 Dec 2023 08:36:33 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300460#Comment_300460 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300460#Comment_300460 Sun, 26 Feb 2023 20:36:30 +0000 David Lam Can I pick your brains please.
I'd like to add some IWI to my front wall (victorian terrace with a bay window). It's quite a small area and I plan to have max 60mm insulation. So tiny job really.
It's partially to make the walls plumb as I've now had high quality windows installed.
My main issue is that the wall is highly irregular.
The plan is to frame it out so the wall becomes level and plumb and true with the windows. This will create a small cavity which I would like to fill with insulation.
However if I used batts there will be lots of gaps as the wall above the window sticks out about 50mm more than the below the window.
I thought about boarding it out with OSB and then shoving something like Gutex thermofibre in it.
This is the sort of blown insulation that you're supposed to use a special machine for which would be ridiculous in my situation.
What do you think? Do you think using the blown insulation but just pouring it in would work?

Thank you]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300461#Comment_300461 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300461#Comment_300461 Sun, 26 Feb 2023 22:03:33 +0000 tony
I would avoid battens and cavities]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300465#Comment_300465 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300465#Comment_300465 Mon, 27 Feb 2023 10:14:55 +0000 fostertom And if walls are pretty straight/plumc, but rubble-stone-rough, the parge only needs to be thick enough to bury the high spots? Which in some areas would be quite thin, like 6-8mm. Or in that case, governed by the minimum thickness that lime render has to be, for easy application?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300467#Comment_300467 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300467#Comment_300467 Mon, 27 Feb 2023 10:54:12 +0000 Jeff B http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300469#Comment_300469 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300469#Comment_300469 Mon, 27 Feb 2023 11:50:26 +0000 djh Posted By: David LamDo you think using the blown insulation but just pouring it in would work?Generally no. The blown-in stuff is designed to be blown in under pressure to achieve the required and certificated density. There are often equivalent products designed for loose-fill. e.g. we have blown-in Warmcel in our roof, but they also sell a loose-fill product for laying in lofts.

But certainly some blown-in or tipped-in product seems like the way to go for your situation. In our case they blew in to open spaces that they covered with muslin and then we fitted plasterboard over the top.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300473#Comment_300473 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300473#Comment_300473 Mon, 27 Feb 2023 13:36:22 +0000 Doubting_Thomas
https://www.ecologicalbuildingsystems.com/solutions/renovation-retrofit

It looks to offer what you are after, by applying a thick (20mm) levelling plaster first as Tony and Tom have suggested and then insulating & boarding over the top. You may even be able to taper out to different insulation thicknesses if the difference is greater than this.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300475#Comment_300475 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300475#Comment_300475 Mon, 27 Feb 2023 15:08:50 +0000 Nick Parsons http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300487#Comment_300487 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300487#Comment_300487 Tue, 28 Feb 2023 07:20:57 +0000 Beau

Ours is an old barn that was not only uneven but had water coming through on the most exposed walls. You probably don't need this first layer but we tanked with a plastic membrane like Delta, Safeguard etc. Then used adjustable screws similar to these into brick plugs in the membrane https://www.fischer-international.com/en/products/screws/adjusting-spacing-screws/adjustable-screw-juss You screw them through a batten and then you can unscrew them but the batten remains attached to the rings under the head. Best when the battens are still a bit wet. Then the controversial bit a layer of multifoil insulation. Then cross battens over the top and plasterboard to finish

I know multifoil in controversial but we ended up with flat walls and an easy-to-heat barn. If using the wood fiber you may still find the adjustable screws very handy for leveling your wall]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300493#Comment_300493 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300493#Comment_300493 Tue, 28 Feb 2023 10:58:57 +0000 fostertom Posted By: Nick Parsonswe used 40, 40 and 20 and 'wrestled' it over a 'wibbly wobbly' parge coat. Needed more fixings than usual, but it worked well.So Nick does 'worked well' mean an aesthetic preference for the original old 'wibbly wobbly' finished walls instead of the dead hand of squared-up modern utilitarianism which also involves significant loss of room interior dimension?

And Beau, I think I've seen your barn, if it's that building, and it's airy and simple enough to look great all straightened up. Excellent idea, those screws - I was not aware of them.

Perhaps I'll start a new thread, but wd love response to my parging Qs a few posts back.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300552#Comment_300552 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300552#Comment_300552 Thu, 02 Mar 2023 09:46:07 +0000 lngn2 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300559#Comment_300559 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300559#Comment_300559 Thu, 02 Mar 2023 13:04:57 +0000 Nick Parsons
''So Nick does 'worked well' mean an aesthetic preference for the original old 'wibbly wobbly' finished walls instead of the dead hand of squared-up modern utilitarianism which also involves significant loss of room interior dimension?''

In some ways I suppose it meant that, as a 'not-a-plasterer' there was no way I was going to (be able to) square that wall up and also that I agreed with the client that a 'rustic' rubble-stone wall did not necessarily want too may straight lines. The 'worked well' mainly referred to the 'wrestling' of the 3 thicknesses of WF board, about which I was by no means certain when I started. Lots of 'fluff-caulking', though.



and

''Perhaps I'll start a new thread, but wd love response to my parging Qs a few posts back.''

Which I guess was:

''Yeah, parge coating - is it OK to use insulating lime plaster?
And if walls are pretty straight/plumc, but rubble-stone-rough, the parge only needs to be thick enough to bury the high spots? Which in some areas would be quite thin, like 6-8mm. Or in that case, governed by the minimum thickness that lime render has to be, for easy application?''

Sorry, missed this one.

Straight answer, I do not know, but since the parge coat is, for me, a 'wet' air-tightness layer I cannot see why an insulating plaster would not work. I always use lime, for breathability, and many (but not all) insulating plasters contain lime. I tend to go for 6-10mm, but there again I am no longer contracting on a regular basis, so it's a bit more theoretical now!

I hope that's of some use.

Cheers,

Nick]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300561#Comment_300561 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300561#Comment_300561 Thu, 02 Mar 2023 13:56:38 +0000 fostertom Anyone else?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300575#Comment_300575 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300575#Comment_300575 Fri, 03 Mar 2023 09:54:08 +0000 GreenPaddy
Is it OK to use?? I explained to the people at "Ecological" what I was going to do and they had no issues. I can't say for sure if it was air tight, but at about 20mm thick, it certainly gave a homogenous appearance.

I installed a timber stud frame (with frametherm32 wool between studs), so I wasn't too concerned about parge coat appearance... though I got the builder to draw a straight edge over it, to remove ay high spots, in a vaguely plumb manner

I used the insulated render rather than just lime, to capture a bit more insulative build-up. In hindsight, since I added insulation, it might have been more cost effective to use regular lime, and do a bit more with added insulation layer. You gotta try these things sometimes, and not just contemplate.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300578#Comment_300578 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300578#Comment_300578 Fri, 03 Mar 2023 10:35:30 +0000 fostertom
Shoulda before - am starting a new topic to continue this, hopefully http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17765]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300583#Comment_300583 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300583#Comment_300583 Fri, 03 Mar 2023 14:16:19 +0000 WillInAberdeen
I've been nervous about wool in contact with cold/cool masonry, due to potential condensation on the masonry surface that soaks into the wool. Many IWI suppliers seem to recommend either: moisture-buffering IWI (woodfibre, cork plaster, etc) that can absorb said condensation and wick it back into the room; or moisture-resistant IWI (foiled&taped polyurethane insulation boards, etc).

How did the mineral wool insulation fare? As you said it is great if it has been tried for real!]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300606#Comment_300606 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300606#Comment_300606 Sun, 05 Mar 2023 11:00:39 +0000 Beau

And Beau, I think I've seen your barn, if it's that building, and it's airy and simple enough to look great all straightened up. Excellent idea, those screws - I was not aware of them.



Hi Tom.

Yes, it is how we did the barn you have seen. Screwfix used to sell the adjustable screws but not sure of the best source these days.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300616#Comment_300616 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300616#Comment_300616 Mon, 06 Mar 2023 08:23:43 +0000 GreenPaddy
I expect the inch of cork parge, and the lime mortar joints, will control any vapours, with travel in both directions. My feeling is that once it's parged, there won't be any of the fortuitous ventilation, to spirit away the moisture, so I want it to travel back into the house or through the lime mortar in "dryer" months.

We've got some cold weather coming this week I believe, so might call in and ask if I can open a couple of socket back boxes.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300710#Comment_300710 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300710#Comment_300710 Sat, 11 Mar 2023 11:04:23 +0000 GreenPaddy
The stone walls with 20+ mm of Diathonite were dry to the touch. They also felt warm, or at least not cold, but that might be the cork reflecting the warmth from my hand rather than actual wall temperature?? Considering it's been minus 10oC the last few nights, quite a lot of winter weather already occurred, and one of the sockets was part of the open plan kitchen (higher humidity challenges perhaps??), I'm comfortable that this approach, for this particular house works.

Plan to repeat it on two similar current stone cottage refurb projects. My GUESS is the parge coat of Diathonite makes a big difference at the wool insulation interface.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300712#Comment_300712 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300712#Comment_300712 Sat, 11 Mar 2023 11:26:59 +0000 WillInAberdeen http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300716#Comment_300716 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17757&Focus=300716#Comment_300716 Sun, 12 Mar 2023 11:51:21 +0000 djh Posted By: GreenPaddyThey also felt warm, or at least not cold, but that might be the cork reflecting the warmth from my hand rather than actual wall temperature??Yes, what you feel is moderated by the 'admittance' as well as the temperature. That's why metal feels cold, whilst sheeps wool etc rapidly feel warm. Metal conducts heat away rapidly, whilst wool or cork doesn't so its surface temperature rapidly rises to match your hand. What you feel is whether you're losing or gaining heat to/from a surface.]]>