External wall insulation

m0t

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My concrete rendered walls were sprayed with a paint type finish before we brought the house, unfortunately they failed to prepare the walls at all so it is now coming off in big chunks.

I've started stripping the paint off using a pressure washer and it's mostly coming off fairly easily (although it is very messy). This has revealed a lot of cracking in the render below that will presumably need repairing prior to repainting.

I had the walls looked at by a plasterer/renderer last year and he thought the best solution would just be to fix external insulation to the exterior because this would only require knocking off the loose paint and would be fairly quick.

My local council is offering 50% back on ewi until the end of Sept but the part that is putting me off is the total cost. The scheme indicates total cost of around £13k for a semi, so I would need to find £6.5k, which seems ridiculous.

I had a look and priced up the material at £2.5k for 65m2 and having watched a slightly bigger house round the corner get done by a single bloke in about 6 days can't belive that it's £10.5k for the labour involved (which apart from the rendering appears fairly low skilled).

Has the scheme massively overestimated the costs in their literature (I'd have to pay £100 for an assessment before I could then ask for a quote )?
 
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Looked into exactly this for a client recently. The quote for 75m² of EWI was £22k, which seems very high to me and didn't even state which product they were planning to use. (client would have had to pay 50% of that) I called the company and asked them for some info but they were not forthcoming at all. I eventually got out of them that they were planning to use an expanded polystyrene product which is nearly 100mm thick. When I asked him about rates he said he didn't know the rates per metre. I asked him how long they anticipated the work taking - he said he didn't know. When I asked him about the render finish he put the phone down. I advised the client to go elsewhere but when I tried a couple more companies they weren't much different. One bloke told me he wouldn't give me their rate per metre because 'he had to be fair to the other companies'. Whatever that bullshit means.
 
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Couple of years ago I was quoted £80/sq m excluding scaffolding and misc nonsense (moving guttering mainly)
 
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Couple of years ago I was quoted £80/sq m excluding scaffolding and misc nonsense (moving guttering mainly)

I'd consider this reasonable when compared with the rates I paid to a gas safe plumber, registered spark and a pair of plasterers.

The other thing that hacks me off is that our taxes are paying part of these costs and the charges are far higher than they should be.

If it wasn't for the building control I would have a bash myself since 75% of the wall space is at ground level (the rest is scaffold tower territory).
 
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And you probably won't get the grant if you DIY (like all the other Green Deal stuff)
 
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And you probably won't get the grant if you DIY (like all the other Green Deal stuff)

True but if it costs me £2.5k for materials and worse case another £2k for rendering then I'd probably still be ahead on the circa £6k green deal cost.
 
And you probably won't get the grant if you DIY (like all the other Green Deal stuff)

True but if it costs me £2.5k for materials and worse case another £2k for rendering then I'd probably still be ahead on the circa £6k green deal cost.
And you wouldn't get a bunch of monkey's doing the work either.
 
Are there BRE standards laid down for the work? I was thinking of the detailing, such as above and around window recesses, under window sills, what to do with the Gutter/drainpipe/ power cables/TV aerial cable/ BT landline cable. . . What about cheapo fixings that let go due to rust or only stainless steel including the mesh and render stops?
Frank
 
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It's all hypothetical but phone and TV cables aren't a problem because they all enter through unrendered bits.

Gutters on 2 sides would need to be moved the rest are attached to fascias (which need repainting incidentally). I have 3 pipes coming out the wall (kitchen waste, bath sink and bath) that would need extending.

Suspect cills need extending plus extension required under tiles to cover top of insulation (house round the corner has a upvc trim here that looks fine).

In terms of windows they put the insulation on the wall up to the reveals but didn't put anything in the reveals and just rendered them so they are all square, looks good. They did have to shape the insulation next to the bay window at an angle.

I made a call to the company running the local scheme this morning and an waiting for a call back. Will update when I have spoken to them.
 
I had EWI installed on my 4 bed detached last spring. The total cost was just under £20k. We paid about £13k of that.

Our 'system' was provided by Alumasc and consisted of Kingspan Phenolic boards 60mm, reinforcing mesh scrimmed on top with adhesive, then a grey-coloured render 3-5mm thick, then a primer and finally silicone top coat. The whole job took about a month, stop and start due to a few muckups with ordering the wrong colour top coat.

You are quite right to point out the issue of detailing around windows, cills, eaves, and etc. This was one place where the eastern Europeans that were subbed in to do the work were just left to their own devices, making it up as they went.

They blocked all of the window weep holes and left multiple places where water could get into the system (e.g. behind gable end verge trim), so I would strongly recommend that you don't let anyone start the job without knowing clearly how they'll finish these tricky areas. The window cills are awkward to put right if they use overcills and block the drainage slot. I had to spend another 1.5k on aluminium overcills and fitting to fix up the mess the original installation co. left.

Most of these issues are sorted now, the house is much much warmer, looks a whole lot better and our energy bills went down from £180/mo to £104/mo (you have to take this in context with the mild winter and falling energy prices of course).

Would I do it again? Yes, but I'd use a different company - perhaps a smaller local co. instead of one of the biggest!
 
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On the face of it yes. But there's more to it than that. The house needed re-rendering in any case (we had water coming through one wall in last year's wet winter). So the net payback is probably quite a bit shorter. And it's a lot more cosy than it was prior to EWI.

Seriously, before we had EWI the 2 winters we had in this house were not comfortable. It's much, much better now. I would do it again even if the payback was longer....

and I probably won't ever buy a house with solid walls again!!
 
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Ouch, that's quite a cost. Thanks for the tips on what to look for.

Had the call back from the scheme provider and am now waiting for an appointment with the contractor who will quote.
 
Having mine done at the moment. £100 per square meter all in. (145sqm) I could have put the insulation on myself but no way the multiple coats of render. Its also aken many man weeks. Some days there have 5 guys working on it. I did get the grant but just £3750.

Looking good so far but agree about detailing.
 

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