Cavity wall injection insulation

David _b

David _b

David _b

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N Ireland
Anyone on here know much about it or even went from not having it to getting it done and notice much difference?

Is there much or any difference in media used?

Got a quote today of 490 minus 150 grant so 340£ to do a gable end, front and rear of my house. Guy showed me the media, silver polystyrene balls that have a light resin to make them stick together

Just curious, want it to be done right :)
 
Make sure it's done properly. Next door noticed whole wall was empty when they knocked an old extension down.
 
The in-laws had theirs done 2 years ago, now getting damp on the inside of some walls. Can be a side effect of the cavity being completely filled so be aware.
 
I have had my house cavity filled and the gable end does get slightly damp to the touch, especially behind my fitted wardrobes :( but as long as you air the room out daily and we have some damp traps hidden away in corners then it doesn't become a huge problem.

It was done under the hard to treat scheme 18 months ago for free as a government project paid for it :D noticed a huge difference in heat retention straight away.
 
To be honest I am looking into it to hopefully help a current condensation problem on walls that seem to form damp
 
Don't do it!

I have never been a fan of blown cavity wall insulation and always refused to have it done, even when it was free. Now it appears many have been oversold and unsuitable houses are now experiencing damp problems.

Check this out from Which.

http://www.which.co.uk/energy/creat...ulation/cavity-wall-insulation-damp-problems/

now it also appears that claims companies are now pursuing damages, it's the new PPI lol.
 
The cavity is there for a reason. I've had problems from 15 year old blown fibre and I've also seen many other properties with damp problems caused by cavity fill.

I'd rather buy a jumper. Maccapacca FRICS
 
I had it done to our place. Not sure how much warmer our house is but it's much quieter... All done for free via British Gas, somehow.

Can't say we've noticed any damp, we're pretty good with opening windows when we're drying stuff/showering and the property was surveyed before it was done to make sure it was suitable and there weren't going to be problems.
 
Don't do it, this is what happened to the house we moved in to last year.

+Just to add this is an 1880's house that went like this within 2 years (south facing wall) after being 'dry' for as long as the previous occupant could remember.

We had the insulation and the mould removed by 'The Mark Group' who admitted it should never have been installed in the first place (for a host of reasons) but it was painful and did more damage to the wall ties and bricks in that wall in that time than the previous 100 years as it remained wet for the entire time. (It was installed for free, previous owner was 92 at the time, draw your own conclusions, they also insulated the roof to 270mm according to the job sheet I found, but I could only measure 150mm)

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avoid like the plague, the cavity allows the house to breath so moisture can escape.
you fill the cavity you create a whole host of damp problems.
 
David _b said:
Right enough of that plan lol


Plan C. (That was B) is fit a positive air system, nuair drimaster Heat jobby
Click to expand...


So you're doing this for insulation or humidity reasons? As a PIV unit won't make your home any warmer, it's there to reduce air humidity.

If you want to make your home warmer without using cavity insulation you need to look at external insulation (costly), or put a jumper on :D
 
Ye, my main drive was because of a few spots of black damp on internal walls. I was thinking if I can insulate the wall cavity then the internal wall will hold more heat and any humid air won't condense on it
 
Hmm some of the expanding foams are carcinogenic, can trap moisture/between the outside brick and inside block.

Better to rip down the plaster to the block, install another insulation layer and then replaster over that. You may loose an inch but less issues than the cavity fill.
 
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I'm not really worried about how hot or cold the house is, just need to stop the damp. I fitted trickle vents the other week to help air flow outwards, hoping with PIV it should sort it long term
 
I put 50mm of celotex on internal walls.

makes a massive difference, see below - 1880's house and the heating is off overnight, I lose no more than 1 degree.

it also has the effect of removing the opportunity for the warm humid air inside the house to hit cold walls, so no damp* (*from condensation, actually I'm getting penetrating damp but that's another story! :() either.

5jxqknaepcf7wl7vtre6yrleacokmyj3.png
 
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Ahh yes- this house had really bad walls you could see the block pattern in our living room. We had mould in the corners too of fitted wardrobes. I inspected the outside gable wall of the house and the pointing - found several holes and used some 15 min quick setting concrete to fill. Job done - two years and no block pattern, even with our massive amount of rain this year..

Rules I follow are - reduce condensation from the kitchen and ensure enough warmth so that you don't get condensation on the walls. Having a good extractor fan in the bathroom too. Once in a while just open the windows in the house after having the CH on.. let all the moisture blow out. We also have two moisture traps - one in the conservatory and one in the kitchen (no cooker hood until we refit the kitchen :/).

During the boiler replacement search I noted that if your boiler is faulty it can leak CO and moisture back into the house.
 
dctek said:
I put 50mm of celotex on internal walls.

makes a massive difference, see below - 1880's house and the heating is off overnight, I lose no more than 1 degree.
Click to expand...

That's the stuff I'd prefer to fit here - between block and plaster.

It also works for the roof too. Currently I have the silver bubble wrap lining the roof and two sets of insulation down between the joists.
 
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