Alternatives to cavity wall insulation

[surreydave]

Just had a visit from an insulation company regarding wall insulation and the surveyor tells me that the cavity is too small in our 1903 built house. The cavity is only 3" and he said it needs to be a minimum of 5" to enable them to carry out the work.
Are there any alternatives to cavity wall insulation??? Our front wall faces north and that part of the house gets very cold in the winter.

Anyone got any ideas?? I have done the loft to 270mm across half of it and moved the loft boarding towards the south end of the house (we have a lot of stuff in the loft and not much storage elsewhere!!).

All ideas welcome!!
Many thanks

 

[Lime]

I'd try a different installer.
The 5 inch requirement may be to do with the insulation material the company use, others may be different.

 

[Feltwell]

I agree with Lime - shop around.

It's rare to get a house as old as 1903 that has a cavity at all, most would still have had solid 9" walls. A 1930's house I used to own had quite a narrow cavity, that had been insulated with what looked like rockwool, arranged by a prevous owner. It's blown in through holes drilled in the outside - with a smaller cavity I can imagine you'd need more holes.

I think you used to be able to get polystyrene beads blown in, which I would imagine would flow better.

 

[AMc]

Are there any alternatives to cavity wall insulation???

The alternatives to cavity wall insulation are internal insulation or external insulation on the wall.
Internally you build a stud wall against the internal face of the wall, fill the gaps with insulation then plasterboard (or insulation with plasterboard attached) over that, then skim with plaster.
Externally you do more or less the same thing but render or clad the external surface.
Both options are quite disruptive and change the window cills/boards, reveals etc. all of which can change the character of the house.
We're in the process of internally insulating the walls in part of our house to comply with building regs for the rest of the work. I wouldn't recommend it unless you are stripping back and renovating the whole house.

I agree with Lime & Feltwell - as you've got a cavity then I would try and find someone with a suitable blown material for the space you have.

 

[chuckey]

I find your surveyors remarks a bit disconcerting because the "standard" cavity is 2" !!! In my case the blown poly beads were priced at 5 Cu metres and a 2" cavity, but they actualy had to use 6 Cu metres due to the cavities being a bit wide. Very pleased with the results.
Frank

 

[surreydave]

Thanks for the comments. We had The Mark Group round to quote (via EON) and I read on the web that they are very good esp. with period property. The house is definately unusual in it build, being so old but with cavity walls. It was built by a brickworks (Dorking) as Site Manager accomodation and so was a bit of an experiment from what I understand. The mortar joints are much smaller than most and the bricks are incredibly hard so I don't want to ruin the look of the property and put 25/30mm holes all over it! Mark Group only use a 22mm drill bit which is appartently the smallest one used by any company and would have just about worked (I was still worried that 22mm would ruin the look aswell!).
I'll get onto someone else and see what they say, I was surprised that a 3" cavity was too small!

Thanks fothe input

 

[AMc]

Something that came up in a fairly recent thread about loft insulation is that the government grants to subsidise installation are very selective about the levels of insulation in place already and the new installation meeting the building regs minimum.
It could be that it's uneconomic for the EON installer to blow insulation into a 3" cavity because it won't provide sufficient benefit to trigger their subsidy? I'm not saying that's the case but as you're quote is via an energy supplier there may be a case for getting an independent quote from someone else.

 

[Mike6]

Hi
Cavity walls are fairly common by 1903,the earliest i have seen is 1869-with bricks as wall ties.Be careful if there is any chance of damp penetration.Some insulation can trap the moisture and allow it to cross the cavity.Ge the cavity checked for debris before you commit.