Cavity expanding foam with wool insulation?

eamon11

hello everyuone,

my house is cold an I want to insulate.
However it already has mineral wool which dates back many many years
I suppose to some other owner. Anyway it doesnt seem to do much.It sags a
lot im told and is water absorbant.They cannot do the beads because of it an
can only do an expanding foam spray which will compress the wool.

Do u think this is ok?

Thanks a lot

Eamon

heinbloed

The sagging - if present- can be checked with a thermal image camera. This would show 'hot' spots on the wall where there is a thermal bridging.
Dampness of the walls can be checked with a hygrometer.

Foam has to have free space to expand, the bubbles won't be created by the gas if glasfibres 'puncture' them.

So check for the reason why the building feels uncomfortable.

Maybe there is floor insulation missing, bad windows etc.,maybe the heating system needs an overhaul or replacement.

Are there any signs of mould or discolouration at the internal walls?Wall papers coming off,the paint blistering ?

A structural surveyor would be the right specialist to ask to do a total check.

brendankelly

Eamon. This is the same debate as the stuff in your attic. Heinbloed will give you scientific reasons why this should be removed and not replaced with more crap. I will tell you the same from practical experience and others will tell you leave it there and pump more crap in on top of crap. Others will tell you it is there for 30 years and is harmless and PVA, Expanding foam and silly cone will fix every thing.

Nonmonotonic

Brendan, you old cynic, thats a lot of crap!;):)

Eamon, how do you know there is mineral wool there, is it dry lined? Why cant beads be used? Dont worry about the wool being compressed if its not doing its job.

TENEGUIA

Hi eamon
I got 100 mm isulated plasterboard fitted great all round coverge and heat retension good value as well.
i will pm you the contractors email get a quote

brendankelly

I did up my daughters home a few years ago and it had this crap in the cavity. It had all sagged down to about a foot above DPC level and was wet , mouldy crap that was creating a bridge for moisture to travel from the outer block into the inner block. We poked the lot of it down under the DPC with a 2 by 1. We had to replace all the windows anyway so we worked from the window opes. My daughter got a good deal on the house because it was damp.cold and mouldy.

eamon11

Thanks for replies,


Have checked at the fuse box and the wool is there.However its not rolls but blown in fibers. Also up in the attic on the inside gable end walls there are the drill holes left, all in orderly sequence. Coming out of these holes are some of this stuff.
in the process of upgrading attic insulation at the mo.
Heating system was overhauled. Windows are double glazed. Floor insulation was partially upgaded. A big issue might be the windows. Although they are double glazed, they are hugh. 3m in lenght and 100 cm high. I suppose the best thing would be to get this thermal imaging done. But if they results are bad, what can I do? Taking out the windows to compress the stuff down is a big job.

Thanks again

Eamon