Foam cavity wall insulation

[mike]

Anyone any experience - good or bad - of pumped foam cavity wall insulation?

Is it worth having? Are there better alternatives?

Are there any disavantages --- formaldehyde emissions or increased risk of damp penetration?

How do they stop it going where it's not meant to be --- is it likely to block airbricks and cause problems with suspended timber floors?

Any tips for picking a decent installer/ questions to ask/ guarantee to expect?

Thanks for any advice.

Mike

[Set Square]

It is well worth having cavity walls insulated. You will notice an immediate benefit (in winter!) in comfort levels - quite apart from the fuel savings.

I don't think formaldehyde-based products are used much (if at all) these days. My father-in-law recently had his bungalow done using something called "Knauf Supafil" in which a candy-floss-like material was used, which formed into small beads as it passed along the injection pipe.

Depending on the current level of insulation of your home there may well be (non-means-tested) grants available to assist with the cost. My f-i-l got half of his paid for with a grant - and he's not on any state benefits apart from a state pension.

You should start by contacting your local Energy Efficiency Advisor. I believe that ringing 0800 512012 will get you to your local office regardless of where you live. They will tell you about grants, and will also put you in touch with competent local installers. AIUI, the approach to the installer needs to be made by them rather than you in order to qualify for any grant.

A competent installer will ensure that the air bricks are not blocked - and will also do a before and after smoke match test on any working chimneys to ensure that they haven't accidentically become blocked. The risk of it going in the wrong place is small because they drill a matrix of holes (less than a metre apart, I think) and only fill a small section of wall through each hole.

The modern material apparently doesn't transmit moisture in the way that earlier materials did - so it doesn't matter of some goes into the cavity below the dpc.

HTH.

[mike]

Thanks for the info, SS.

Mike