External Wall Insulation cost

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dodo

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Has anyone got the external insulation into their external walls of their house , what was the total cost and what was the grant. looking to see if there is value getting a 3 bed semi built in the 97 more energy efficient. tks
 
I’ve had it done. A few years ago. Detached house. 3 sides externally insulated. Last side internally insulated (part wall issues- neighbor wouldn’t let us insulate from their side- long story).

100mm external insulation. Acrylic render finish

Total was 21850
Grant was 6050
Net to us 15850
 
dodo said:
Has anyone got the external insulation into their external walls of their house , what was the total cost and what was the grant. looking to see if there is value getting a 3 bed semi built in the 97 more energy efficient. tks
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You really really need to be sure you are comparing apples to apples here because there are many ways of doing ewi, some are excellent and some are, lets say, lacking.
 
A few years ago I had a figure of 90 euro per sq m for external insulation. See if you can get a ball park figure like that and work out rough idea yourself.
 
€25k before grant. That included replacing a flat roof with an insulated one and pumping the kitchen extension.
 
I got quoted €125 per sqm at the ideal homes exhibition recently. Wasn't impressed by the company in question anyway so didn't follow up on it with them but are looking locally instead. Most of the providers seem swamped and the quality and speed, at least to this laymans eyes from what I see when I am out and about does seem to vary considerably
 
Micks'r said:
there are many ways of doing ewi, some are excellent and some are, lets say, lacking.
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Hi,

Can you elaborate on the good ways of doing this job. Spoke to 2 architects some time back and neither recommended it. One of them questioned that there is only a 15 year guarantee on the job and wondered what happens after that if anything goes wrong. I didn't get the time to question them for long on the merits etc.
 
No particular expertise in this area but I get the overall impression that "bang for your buck" is poor for ewi compared to other possible spending, eg attic insulation, solar PV, doors and windows.
 
Sue Ellen said:
One of them questioned that there is only a 15 year guarantee on the job and wondered what happens after that if anything goes wrong.
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Funny that, they're happy enough that the standard structural cover for the house itself is only 10 years and limited further to 5 years for certain issues, but expect EWI to last longer???
 
Right Winger said:
No particular expertise in this area but I get the overall impression that "bang for your buck" is poor for ewi compared to other possible spending, eg attic insulation, solar PV, doors and windows.
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It's going to depend on the house but agree on attic and windows etc. big advantage of EWI against internal dry lining is that you don't lose space or have to wreck the inside of the house. Also, once it's plastered and painted over, it can be a good way of literally covering over pebble dash.

personally, I've seen 2 where the house looked really better once done and one where it looked botched
 
Sue Ellen said:
Hi,

Can you elaborate on the good ways of doing this job. Spoke to 2 architects some time back and neither recommended it. One of them questioned that there is only a 15 year guarantee on the job and wondered what happens after that if anything goes wrong. I didn't get the time to question them for long on the merits etc.
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The creation of thermal bridges is one of the main considerations with adding insulation to a building and especially true for ewi. There are 3 places generally where these tb's occur; top of wall, bottom of wall and around windows & doors reveals. Thermal bridging not only allow excessive heat loss but also significantly increase the risk of mould internally. Therefore, thermal bridging should be designed out where possible. Depending on the building, you achieve this by extending the insulation down to the wall footing, up past the soffit to the top of the wall (and ensuring the roof insulation seamlessly meets the ewi) and move the window / door frames outwards to be overlapped by the ewi.
What I often see quoted for is going only to the path level on the bottom, soffit level on the top and the windows & doors not moved outwards.

I also find that the knowledge base on the above is poor enough with quite a bit of misunderstandings on the subject leading to less than desired outcomes.

Also, in the majority of cases, the actual insulating material is the cheapest element of the ewi install and for example doubling the insulation thickness from say 100 to 200mm might only add maybe 10|% to the overall cost but make quite a bit of difference to conductive heat loss.

There are many buildings with well installed ewi in place for many decades without issue and if an issue arises I don't see why it couldn't be repaired / addressed like any other building defect. However, if you have a budding county hurler in the household who likes bating a sliotar against the gable wall then perhaps ewi wouldn't be the best choice!

Finally, there is little point in getting ewi done if your airtightness weaknesses are not addressed.
 
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What was included in this quote? Was the ewi being extended to the footings, to the soffit, etc. as per Micks'r comment?

I've seen a few houses in my estate and the standard is v poor, obvious thermal bridging that with a little effort could have been addressed.
 
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