I'm looking to insulate an old 1930s built house, it's very drafty in the winter, i've been looking about and have come across a liquid based foam that turns into a foam type planket for the solution to keep heat in, I understand that you inject this liquid A and B stuff into the wall and it expands into a foam, although my concern is, that when injected correctly every bit of space in it's way will be feeled with foam, and am i correct in saying that if I do the whole house, there will be no way for the house to breath, or is that why we have windows? Also, you have pipes and electrical wires in the walls, if I spay this stuff over/on top would I be likey to cause a fire hazard or give my self a problem when maintenance comes around for pipes and electrical wireing in the furture?

Cheers,

Some houses are not suitable for this type of insulation, there was a case not so long ago where this stuff was used on an early 1900's house, among other things it blocked the air bricks, leading to dry rot and rising damp..putting it right cost a fortune,

My advice would be to get an insulation specialist to assess whether your property is suitable or not before proceeding.

_________________
.

If you feel you have benefited from the Free advice given on the Forum, Please consider making a donation to UHM's Nominated charity, read all about it and donate here :

http://www.donnasdreamhouse.co.uk/


__________________________________
__________________________________

Verwood Handyman
I Know it says I'm On-line, but I might have just left myself logged in, whilst I'm out....

not really the answer i was looking for but surpose it's better being told the truth, cheers

The better way is to have loose polystyrene 'balls' injected into the spaces.

_________________
This post may contain nuts

What type of finish is the exterior walls, ie if they are rendered go for external insulation with a new render finish.
Spray and expandable foam will cause all kinds of problems.

Kelly do you mean something like this?

http://www.myonlinediary.com/wall-insulation/

Hi YidDannyK,
Spray foam is an excellent product but does have its limitations, we are spray foam applicators and do cavity wall injection. Im not on here trying to sell you a product but can help you decide if its right or wrong for your property. You will need a survey which any good company will do for you free of charge. Spray foam when injected will fill all the gaps, its injected with a much smaller hole pattern than beads of fibre and during the process we inspect the filling process using a borescope. It is superior in the fact that it bonds the inner and outer wall together, where wall tie failure has occurred the foam combats this problem. It will totally seal your property and a great vapour barrier.

The below is not my product or my website (somebody will have to say something)

Have a read about the product here . http://www.isothane.com/pdf/Technitherm ... tSheet.pdf they also have a video to watch the process.

The cost of foam is greater than any other wall insulation, but in my eyes used the the right property its far superior. It allows smaller cavities to be filled, often anything less than 50mm and the other companies will not touch it.

With regards to ventilation you will find that your house will already be ventilated, windows, doors, loft insulation all give plenty of ventilation to your property.

With the foam you will get a seamless thermal barrier so no air leakage will occur. The R value is about 6 per inch depending on what foam is used and the U value can come down to about 0.3 depending on your wall structure. People always write about spray foam will cause problems but im yet to see any in my years of applying it, never has anyone showed me a picture with a defect caused by spray foam.

I hope this is of some help with your choice.
Regards