Cavity Wall Insulation

[Squirrel_Basher 17,100]

Let's put it to rest shall we .Cavity full fill is only as good as the firm doing it .The polestyrene balls are very good if forced in properly and cover the WHOLE cavity which is only done by holes drilled no further than 1.2 apart (4 ft ).

If done further apart cold spots will be left ,the whole lot then sinks in time leaving a gap up high in bedrooms where mould develops .Modern celotex (the dense silver foil coated stuff)works best when in contact with a warm heat source is the under leaf or concrete floor ,plasterboard etc that is within a heated area .The theory is that the celotex holds the warmth transferring it to nearby materials ,easily tested by sitting on a sheet for a few minutes lol.Trust me I'm a builder lol.

[Fly The Boy 339]

Parents have it in bungalow and and house is too hot, before was grand, now u can't breath in the house to stuffy....

[scothunter 12,609]

I did it as a job for years.IF its done properly they shouldn't be any problems.

However if you're wall ties are thick with old mortar or rubbish (bits of wood half bricks etc ) it will cause voids and dampness. I have seen brickies tip there mortar boards and rubble down cavities.

 

Also good fitters are hard to find these days and with the goverment grants for warm deal these companies are hiring anybody and have know clue how to set up the machine or a proper drilling pattern. IMO if you aren't sure whos doing it dont get it done. Seriously it can f**k a house up.

[The one 8,505]

But its no polystyrene balls now they use old sheeps fleeces as its more natural and they hold water

[whiteracer 258]

I did it as a job for years.IF its done properly they shouldn't be any problems.

However if you're wall ties are thick with old mortar or rubbish (bits of wood half bricks etc ) it will cause voids and dampness. I have seen brickies tip there mortar boards and rubble down cavities.

 

Also good fitters are hard to find these days and with the goverment grants for warm deal these companies are hiring anybody and have know clue how to set up the machine or a proper drilling pattern. IMO if you aren't sure whos doing it dont get it done. Seriously it can f**k a house up.

The lad I had round put it this way didn't feel my head with confidence, I have a conservatory on the back and he wanted me to pay out for scaffolding otherwise they would need to drill in thru my daughters bedroom ( just been decorated) I asked him what it is they pump in and he said 'rock wool'!! Think I pissed him off as made him take his shoes off as he wanted to go all round the house and the carpet hasn't been down long! Bollox to it I ll turn the heating up a notch ....... I personally don't think it's needed but the wife keeps moaning she cold all the time while she sat in a jumper and a blanket over her while I am in shorts ?

[villaman 9,983]

When we've done new build houses weve used kingspan insulation boards that are held to the inside course . There is wall ties that attach the outside and inside courses and we always try to keep as much cement from falling on them because they act as a bridge for water if their covered in cement . Few days after laying the blocks so the cement is all dry we (usually me) is up above the wall with a length of battern and a torch checking if any cement is dried on the metal . If it is I use the battern to tap it off. I'd be pissed off if someone came and filled it all with something

Building inspector told me they checked 1000 house with kingspan or celotex in and 1000 houses failed ,because to many gaps in between sheets

[stumfelter 3,034]

 

Damp is not going to travel through the foam insulation is it.

wow a scientist, new houses have a layer of foam attached to the inner skin but the cavity is wider to allow an air gap, in older houses the cavity is a bit narrower and some smart ass sales man comes around and tells you it's best to insulate, you then pay him an arm and leg and in return he sends round a van with a pump a couple of tons of recycled rags and a pair of retards, they then drill holes all over your house and pump in the shitty mess stick a bit of shit in the holes and gel on, over time the recycled rags get wetter and heavier slowly sinking to the bottom of the house therefore causing a soggy wet cavity that is bridging in the damp by the bucket load, I think that's the best I can do without a blackboard and chalk

Your answer is a bit vague, should he have it done or not?

[Welsh_red 4,719]

 

When we've done new build houses weve used kingspan insulation boards that are held to the inside course . There is wall ties that attach the outside and inside courses and we always try to keep as much cement from falling on them because they act as a bridge for water if their covered in cement . Few days after laying the blocks so the cement is all dry we (usually me) is up above the wall with a length of battern and a torch checking if any cement is dried on the metal . If it is I use the battern to tap it off. I'd be pissed off if someone came and filled it all with something

Building inspector told me they checked 1000 house with kingspan or celotex in and 1000 houses failed ,because to many gaps in between sheets

 

 

Gaps between sheets? do you mean whenthey are putting them in their not butting them up tight to each other?

[villaman 9,983]

 

 

When we've done new build houses weve used kingspan insulation boards that are held to the inside course . There is wall ties that attach the outside and inside courses and we always try to keep as much cement from falling on them because they act as a bridge for water if their covered in cement . Few days after laying the blocks so the cement is all dry we (usually me) is up above the wall with a length of battern and a torch checking if any cement is dried on the metal . If it is I use the battern to tap it off. I'd be pissed off if someone came and filled it all with something

Building inspector told me they checked 1000 house with kingspan or celotex in and 1000 houses failed ,because to many gaps in between sheets

 

 

Gaps between sheets? do you mean whenthey are putting them in their not butting them up tight to each other?

 

Not butting up probably or muck causing gaps in between and losing heat from house

[stevo79 569]

 

 

When we've done new build houses weve used kingspan insulation boards that are held to the inside course . There is wall ties that attach the outside and inside courses and we always try to keep as much cement from falling on them because they act as a bridge for water if their covered in cement . Few days after laying the blocks so the cement is all dry we (usually me) is up above the wall with a length of battern and a torch checking if any cement is dried on the metal . If it is I use the battern to tap it off. I'd be pissed off if someone came and filled it all with something

Building inspector told me they checked 1000 house with kingspan or celotex in and 1000 houses failed ,because to many gaps in between sheets

To true and they give you the tape to tape up the joints only trouble when it rains it peals off! Edited March 1, 2017 by stevo79

[Squirrel_Basher 17,100]

Not due to material fail though mate .Slap dash workmanship .We use duck tape on the joints and corners having racked up the inner skin fair high first ,at least to top of windows ,match outside skin and upwards .Dirty wall ties in old houses are the main cause of damp issues I would say .A dry cavity will take any sort of added insulation IMO.

[The one 8,505]

 

I did it as a job for years.IF its done properly they shouldn't be any problems.

However if you're wall ties are thick with old mortar or rubbish (bits of wood half bricks etc ) it will cause voids and dampness. I have seen brickies tip there mortar boards and rubble down cavities.

 

Also good fitters are hard to find these days and with the goverment grants for warm deal these companies are hiring anybody and have know clue how to set up the machine or a proper drilling pattern. IMO if you aren't sure whos doing it dont get it done. Seriously it can f**k a house up.

The lad I had round put it this way didn't feel my head with confidence, I have a conservatory on the back and he wanted me to pay out for scaffolding otherwise they would need to drill in thru my daughters bedroom ( just been decorated) I asked him what it is they pump in and he said 'rock wool'!! Think I pissed him off as made him take his shoes off as he wanted to go all round the house and the carpet hasn't been down long! Bollox to it I ll turn the heating up a notch ....... I personally don't think it's needed but the wife keeps moaning she cold all the time while she sat in a jumper and a blanket over her while I am in shorts

 

Must be a woman thing i come down at night with my shorts on and you get REALLY ? while shes tucked up with a jumper and a blanket then once there past the flush of youth the hot flushes start and they will be wanting all the windows open so im going to give it a miss

[Lab 10,979]

Very interesting. I stay in an old bungalow...around 1920s built. The walls are stone cold and the back room is got a bit mould. I think this is due to the central heating system that was fitted was not the correct one and should have been fitted in a home with mains water pressure...(I don't have that).

So instead of me having these oil heaters in each room...cost a fortune. As someone already asked.....what about these insulating boards that are fixed to the outside of the house and then roughcasted over. Surely they are good?

[Qbgrey 4,143]

if i build myvown house again,i think im going with a 75mm clear cavity and will insulate on internal skin with celotex glued plasterboard or similar.and put a few brick vents in external brickwork to vent cavity around building.

[KES2 171]

I've had both and no damp with the cavity insulation - I'd be tempted to stud the walls on the inside and avoid cavity filling now if I needed more insulation value. Its all a matter of how much it costs and the saving in electricity/gas/oil.

Internal ventilation is also v important. Keeping a flow of air from inside to out tends to compensate for the amount of water now in houses through washing /drying/mopping/showers etc.