External wall insulation to side and rear only?

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David_Dublin

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We've a partial red brick house, front ground floor and corner quoins are red brick. We're end of terrace, gable end is pebble dashed. Ground floor sitting dining on suspended timber floor, return is a few steps down and not suspended, not insulated. Soffit and fascia are solid concrete, it's a 1920s built house.

Plan is to extend at gable end, 2 storey. Considering backfilling the suspended floors to improve insulation and air tightness. We're replacing all windows - a more snug house is a factor on the extension/refurb.

Would it be possible, and make sense, to wrap the back and side of the house with EWI? Leave the front alone, or maybe internal insulation. South facing front, sun all morning/afternoon.

The thinking is to maximise snugness. I don't mind losing some quoins on the back/rear side. And it would avoid having to internally insulate rear and side walls.

Any issues that could not be solved? Any gotchas with the concrete soffit and fascia with EWI and cold bridging?
 
I don't know if you're intending on using SEAI grants but you can't get a grant for EWI to cover anything but all the external walls. There are possible exemptions relating to extensions (which may already be insulated).

It's a similar story for internal insulation, with exemtions allowable for example where a kitchen is fitted to the internal face of a wall.
 
Thanks for the reply. I see some companies do slip brick solutions to allow for recrrating existing red brick look, so that might be an option for full EWI.

Then the only question is in relation to the concrete fascia and soffit, and cold bridging.
 
There is no reason why your concrete fascia/soffit thermal bridge cannot be eliminated with proper detailing. Maybe talk to these guys
 
David_Dublin said:
Thanks for the reply. I see some companies do slip brick solutions to allow for recrrating existing red brick look, so that might be an option for full EWI.

Then the only question is in relation to the concrete fascia and soffit, and cold bridging.
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These do not at all look like a traditional brick wall, and the difference is immediately obvious. It's also nearly always a bad idea to cover historic brickwork. Many many buildings have been ruined from this.

Personally in my own house, I left the front brick wall alone, and insulated well everywhere else. And the house is very cosy. The loss of heat through the wall is counterbalanced by the heat from the south facing sun.
 
tinymouse said:
These do not at all look like a traditional brick wall, and the difference is immediately obvious.
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This is no longer the case. You can get brick slips from salvaged brick even - it's just a matter of specifying the correct final finish.
 
I'm willing to be corrected, but every example I've seen looks completely wrong. Old brick has all kinds of detailing at windows and roofs, which is what gives it most of its character, and you're never going to get it right covering it in slips.
 
tinymouse said:
I'm willing to be corrected, but every example I've seen looks completely wrong. Old brick has all kinds of detailing at windows and roofs, which is what gives it most of its character, and you're never going to get it right covering it in slips.
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You might be surprised with what can be done. In any case, who goes right up to those bricks to see if they're this, that or the other?
 
tinymouse said:
Old brick has all kinds of detailing at windows and roofs, which is what gives it most of its character, and you're never going to get it right covering it in slips.
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All down to the person doing it. It's possible recreate all that character with slips, but it requires a tradesperson who knows what they're doing and isn't just out to take shortcuts.
 
We had the wrapping done seven years ago , The brickwork is just plaster with a dye , From passing our house you would easily know , That does not bother us as our heating bill is less than half of what it was , Unless the whole of the property is insulated you will not receive the grant , Why not dry line the front of the house and wrap the rest .
 
I think we'll end up wrapping the side and back, and internally insulating the front, unless we see VERY persuasive examples of slip bricks being used. @pablo123 - to your point about grants, leaving out the front costs €4,500, i.e. the grant for end of terrace - that's quite a cost. And you'd also forego the internal as you'd be doing some EWI/some internal.
 
David_Dublin said:
I think we'll end up wrapping the side and back, and internally insulating the front, unless we see VERY persuasive examples of slip bricks being used. @pablo123 - to your point about grants, leaving out the front costs €4,500, i.e. the grant for end of terrace - that's quite a cost. And you'd also forego the internal as you'd be doing some EWI/some internal.
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My understanding is that if you mix drylining and external insulation you receive the grant for the one which is the majority. I asked this question of an SEAI rep at an energy-efficiency event as we are going to be in that exact situation (drylining the redbrick front to end-of-terrace house which will have EWI to side and rear) and he came back with that via email.
 
House has suspended timber floors. One option we were consderinf was filling the cavity, cuttong out the joists and pouring a eent floor. This to improve air tightness, amongst other things. Probably no air tightness consideration if doing full EWI, right?
 
David_Dublin said:
House has suspended timber floors. One option we were consderinf was filling the cavity, cuttong out the joists and pouring a eent floor. This to improve air tightness, amongst other things. Probably no air tightness consideration if doing full EWI, right?
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suspended floors have to be vented to avoid damp, insulation or not. Even if you bring the EWI down below the level of the floor (which you should, but my observations suggest a lot of contractors don't bother) you still need vents so the underfloor space will be still be "cold" which can lead to draughts and cold floors.

I don't know if it's cheaper to fill the void or to insulate the floorboards - both options are pretty disruptive. The void under some of our rooms is 5 feet deep so would require a lot of concrete. It's one of the things putting me off EWI (as well as the ludicrous cost and I'm dubious about the longevity and environmental impact of the cladding).
 
shweeney said:
suspended floors have to be vented to avoid damp, insulation or not. Even if you bring the EWI down below the level of the floor (which you should, but my observations suggest a lot of contractors don't bother) you still need vents so the underfloor space will be still be "cold" which can lead to draughts and cold floors.

I don't know if it's cheaper to fill the void or to insulate the floorboards - both options are pretty disruptive. The void under some of our rooms is 5 feet deep so would require a lot of concrete. It's one of the things putting me off EWI (as well as the ludicrous cost and I'm dubious about the longevity and environmental impact of the cladding).
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Thanks @shweeney - I forgot that backfilling would be a requirement for EWI as otherwise one ends up with rotting floorboards. I may be wrong, but I would have thought that there are options when filling deeper voids, i.e. top x cms is concrete, the rest something cheaper .
 
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David_Dublin said:
Thanks @shweeney - I forgot that backfilling would be a requirement for EWI as otherwise one ends up with rotting floorboards. I may be wrong, but I would have thought that there are options when filling deeper voids, i.e. top x cms is concrete, the rest something cheaper .
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you don't have to backfill, just make sure you leave vents to the underfloor void. You have to put vents into your rooms as well, which unless you have some form of baffled vent or heat recovery, is going to undo a lot of the benefit of the EWI as well.

proper retrofitting is expensive and disruptive. My impression is that most people just get the EWI and skip the other bits, how much does this save them on gas/oil and improve their comfort, I don't know. My neighbours have said their house is much warmer since they had it done but they still seem to have an oil truck pulling up outside every few weeks.
 
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