External Wall Insulation

[meic]

The council came knocking on the door offering free external wall insulation, the neighbour is going for it and it seems sensible to have my walls done as well.

Is there anything about external wall insulation that they are not going to tell me?
Long term maintenance?

The walls in question are three foot wide with a rubble filled central cavity, no damp course.
Some parts are concrete rendered with pretty mica chips and others are lime rendered.
Also a fair proportion of one wall can not be accessed as there is a garage 18" away from it.

[thirdcrank]

I presume the scheme is a national one (even international in your case )

Leeds City Council was offering all sorts of insulation schemes earlier this year although we had cavity wall insulation and more in the loft 30 years ago. (I think there were only two houses in the street who still needed it doing.) The council employed what seeme dto be a reputable firm to do the work: the house directly opposite ours was done by people I'd have been happy to have working on my own house. In short, I think the scheme is kosher.

Having said that, when they came round offering the scheme, the person who spoke to me was a bit disappointed when I said "no," even though to somebody who knows about the subject, the evidence of the work having been carried out is plain to see where the holes were resealed. That suggests to me tghat at the stage where they are "selling" it to you, they may not be technically competent to explain the subject and the people arriving to do the work may be the first to appreciate that an individual house is unsuitable. I'd ask some careful questions if you have any doubts.

[meic]

Yes stage one, I imagine was just a salesman.
When stage two arrives it will be someone with technical knowledge and I wouldnt be surprised if he said not a good idea without damp-course.
On the other hand I would not have thought many houses with these sorts of walls have damp-course.

[gaz]

Slightly OT but I recently had a non-salesman call (I know he was a non-salesman because of the way that he opened the conversation, "Don't worry, I'm not trying to sell you anything). His company had done some work recently in the area (certainly true), renovating roofs. He was offering a free survey to see if ours could benefit from their service. "I'm sure there's nothing wrong with your roof" was one of his phrases.

Frankly that was his downfall. I know that there are things wrong with my roof. I was up there on the end of a ladder a few weeks back making temporary repairs. Any trained roofer and many unskilled idiots would be able to see that there are things wrong with my roof.

So given that I know what's obviously wrong with my roof I made an immediate judgement on the competence of his company to deal with the matter and said "no thanks".

[caer urfa]

Hi Meic

This link and other info on this 'site may be of interest?

http://www.energysavingtrust.org.uk/In- ... insulation

Cheers

CU

[meic]

Thanks for that, it does seem quite a gift that I am being offered.

Which makes me think "dont look a gift horse in the mouth"

or was it "If its too good to be true..."

[[XAP]Bob]

Its good, no long term maintenance required, but if your cavity really is rubble filled where will they put the insulation?

[meic]

I am beginning to understand why some of the replies were not quite getting the point.

I am being offered external wall-insulation, not external-wall insulation.


The walls are effectively solid walls with no useable cavity. The insulation is by having the external walls refaced, a much more difficult and costly task than drilling holes and pumping in fluff.

[Deckie]

I've long thought that we put insulation on the wrong side of the wall.

If you put the insulation on the outside of a wall the material in the wall can act as a storage heater releasing heat back into the house - the thermal mass effect. In large parts of the world the external walls of houses are built with materials with a high thermal mass inside the insulation to take advantage of this effect.

[patricktaylor]

I'd steer clear of it. Too risky and could mess up the outside of your house.

[meic]

That is the worry, however if the neighbour is going ahead, I am caught by her decision a bit too.

At present my wall is zero maintenance, quite pretty and looks as if it will stay like that for a century quite easily. I lack such faith in modern materials and workmanship.

[Deckie]

As an addendum to my above comment -

I am not a fan of "spray on" insulation, or render. If not applied in perfect conditions to a correctly prepared and dry wall it can have the opposite effect to that intended and lead to serious damp problems for the property by trapping and holding moisture against the walls.

By external insulation I mean a reasonable thickness of a solid insulation material then clad with a weather protective layer (stone, timber, brick, render, whatever the vernacular architecture of the area dictates). The material used can be whatever your taste / budget / ethics dictate from closed cell foam to dense straw provided it is used in sufficient quantity to impart sufficient insulation for the given property.

[patricktaylor]

... The insulation is by having the external walls refaced ... At present my wall is zero maintenance, quite pretty and looks as if it will stay like that for a century quite easily ...

That says most of it IMO. If you cover the outside walls of the house with something, there is its value to think of as well. A loss of value may well outweigh any benefits (assuming there are some). With walls 3 feet thick I doubt if any external treatment will do anything insulation-wise.

[meic]

I dont think that the thickness of the walls will prevent the insulation being effective.
Old buildings like this have a "steady state" with a days worth of heat stored travelling through the walls.
The outside of the walls loses heat just as quickly as any other wall, it just takes it longer to get there through the wall.

[PDQ]

Energy wise it's a no brainer not to go for it. The house will be more comfortable to live in and you will save a good deal of the folding stuff on your heating bills.
Whether you find the change in appearance acceptable is another question and only one that that you (and your neighbour)can answer.