Phil Mac'avity

[papasmurf]

Well Im just glad all is well in the Duchy and Papa is nice and toasty in  his rockwool insulated prefab . Its people like papa that make you proud to be British , getting by against all the odds ,despite the Tories , food shortages , the NHS , tourists , knife attacks and damp problems . Im just in awe , the man deserves a knighthood .

It isn't a prefab, it is a semi detached bungalow. I am English not British. (Ancestral DNA test.) My wife and I are getting by but a lot of the local population are not.  

[Streetwalker]

Blanket/ insulation  no wonder you've amused SW.

Well Im just glad all is well in the Duchy and Papa is nice and toasty in  his rockwool insulated prefab . Its people like papa that make you proud to be British , getting by against all the odds ,despite the Tories , food shortages , the NHS , tourists , knife attacks and damp problems . Im just in awe , the man deserves a knighthood . 

[cromwell]

Because they were not suitable to have cavity wall insulation or it was installed by cowboys. (That is why I posted the Hansard link.)
You blanket condemnation of cavity wall installation does not fit the reality of the majority.

Blanket/ insulation  no wonder you've amused SW.

[Streetwalker]

[papasmurf]

You may dispute the numbers ,it is though estimated that 25% of retrofitted homes have problems , thats over 2 million homes .Other experts within the industry put the figure at nearer 3 million .

Because they were not suitable to have cavity wall insulation or it was installed by cowboys. (That is why I posted the Hansard link.)
You blanket condemnation of cavity wall installation does not fit the reality of the majority.

[Streetwalker]

There is six inches of insulation in the roof. There are no moisture problems in my home.

The bridging problem you refer to only happens when home has not been built properly, or was never suitable for it.
I dispute your many houses do have a problem.

Nobody gives a monkeys what your happens in your house . Im sure its great ,for now . Rockwool retrofit is probably the poorest of the options of CWI methods with degrading and cold spots common so again well done if you got away with it . 

You may dispute the numbers ,it is though estimated that 25% of retrofitted homes have problems , thats over 2 million homes .Other experts within the industry put the figure at nearer 3 million .
The government will never admit its a major problem as it will derail their green agenda that would see all homes insulated wether its the right thing to do or not . They wont admit its the product or a poor product for the materials used in the original build . Saying its been poorly installed is a cop out and a failure to properly investigate its failures .Thats not to say there were not some cowboys operating in the industry but even that doesn't negate the fact that there are problems that some would dispute 

https://www.thisismoney.co.uk/money/news/article-10390579/Botched-cavity-wall-insulation-ruining-homes-causing-damp-mould.html

[Nick]

My home is not brick built, not are any of the surrounding houses. All are rendered externally. No problems with damp at all in my home since the cavity walls were filled with rockwool back in 1986.

What is the DPC made of?

[papasmurf]

The U.K. has a really high humidity level, houses with a large wall facing a constant prevailing wind and the UK's harsh winter mean the wall will constantly be damp. Depending on the age of the house, the DPC  might be totally inadequate and the outer brick will be wet. The moister penetrates the brick and then tracks across the CWI. This doesn't necessarily mean the build quality was bad. If you pump blown rock wool into a cavity it WILL drop below the DPC and bridge the DPC in an older home. Bad move.

My home is not brick built, not are any of the surrounding houses. All are rendered externally. No problems with damp at all in my home since the cavity walls were filled with rockwool back in 1986. 

[Nick]

There is six inches of insulation in the roof. There are no moisture problems in my home.

The bridging problem you refer to only happens when home has not been built properly, or was never suitable for it.
I dispute your many houses do have a problem.


Cavity Wall Insulation - Hansard - UK Parliament


Although cavity wall insulation was an excellent way to improve energy efficiency in many homes, which it is if it is correctly installed, in those cases it was discovered tragically that those homes were never suitable for cavity wall insulation or that the work that had been carried out was defective.

The U.K. has a really high humidity level, houses with a large wall facing a constant prevailing wind and the UK's harsh winter mean the wall will constantly be damp. Depending on the age of the house, the DPC  might be totally inadequate and the outer brick will be wet. The moister penetrates the brick and then tracks across the CWI. This doesn't necessarily mean the build quality was bad. If you pump blown rock wool into a cavity it WILL drop below the DPC and bridge the DPC in an older home. Bad move. 

[papasmurf]

Every building has different reasons for damp ,I would suggest yours was an internal problem rather than a cavity issue . Filling a cavity with rockwool would make your home warmer (which would solve internal issues) but wont cure any moisture bridging from the outside skin

40 years is a good lifespan for rockwool . It will in time degrade and you will find the top of your house will be without  insulation . Im not saying every house that fills its cavity will have problems , just that many do . A lot will also depend on ventilation and the materials used in the construction. 

There is six inches of insulation in the roof. There are no moisture problems in my home.

The bridging problem you refer to only happens when home has not been built properly, or was never suitable for it.
I dispute your many houses do have a problem.


Cavity Wall Insulation - Hansard - UK Parliament


Although cavity wall insulation was an excellent way to improve energy efficiency in many homes, which it is if it is correctly installed, in those cases it was discovered tragically that those homes were never suitable for cavity wall insulation or that the work that had been carried out was defective.

[Streetwalker]

I had the wall cavities in my home filled with rockwool. It stopped the damp problem. (Still no problem nearly 40 years on.)

Every building has different reasons for damp ,I would suggest yours was an internal problem rather than a cavity issue . Filling a cavity with rockwool would make your home warmer (which would solve internal issues) but wont cure any moisture bridging from the outside skin 

40 years is a good lifespan for rockwool . It will in time degrade and you will find the top of your house will be without  insulation . Im not saying every house that fills its cavity will have problems , just that many do . A lot will also depend on ventilation and the materials used in the construction 

[Streetwalker]

When I had my extension done about 3 years ago, the builder dug the footings and floor out, filled it with 100mm of MOT then blinded it with sand, DPC, 100mm Celotex boards, another DPC, more sand and then concrete, finished off with screed. Walls are Concrete block on the outside, breeze block on the inside and Celotex boards fastened to the inside wall of the cavity. Don't think the heating has ever been on in that room, you can tell the difference when you walk into that part of the house immediately.

Sounds about right Nick , the key being is you have a gap between the cavity insulation and the outside skin which prevents moisture bridging .

[Nick]

https://www.bbc.co.uk/news/articles/cxwwr7vyrj0o


When I was a lad


Doing my apprenticeship the cavity wall was just that ,a cavity . Much of the 'science' behind the teaching was to keep the cavity clear and clean at all times . Inspection of work on site revolved around the cavity, as an apprentice you always got the job of cleaning any debris ,mortar on wall ties .Coring holes were left at the bottom of the wall for cleaning purposes .
The final inspection was a key day on the job , cavity inspection before handing the house over to the roofers , much beer was drunk with a pass ,payday for the subbie and bonus for the lads .

Fast forward 20 years and the fecking idiots are filling them up with foam , bridging the cavity and allowing moisture to transfer into the building . I never let them anywhere near mine , its going to be a big problem for many that did .

When I had my extension done about 3 years ago, the builder dug the footings and floor out, filled it with 100mm of MOT then blinded it with sand, DPC, 100mm Celotex boards, another DPC, more sand and then concrete, finished off with screed. Walls are Concrete block on the outside, breeze block on the inside and Celotex boards fastened to the inside wall of the cavity. Don't think the heating has ever been on in that room, you can tell the difference when you walk into that part of the house immediately.

[papasmurf]

Fast forward 20 years and the fecking idiots are filling them up with foam , bridging the cavity and allowing moisture to transfer into the building . I never let them anywhere near mine , its going to be a big problem for many that did .

I had the wall cavities in my home filled with rockwool. It stopped the damp problem. (Still no problem nearly 40 years on.)

[Streetwalker]

https://www.bbc.co.uk/news/articles/cxwwr7vyrj0o


When I was a lad


Doing my apprenticeship the cavity wall was just that ,a cavity . Much of the 'science' behind the teaching was to keep the cavity clear and clean at all times . Inspection of work on site revolved around the cavity, as an apprentice you always got the job of cleaning any debris ,mortar on wall ties .Coring holes were left at the bottom of the wall for cleaning purposes .
The final inspection was a key day on the job , cavity inspection before handing the house over to the roofers , much beer was drunk with a pass ,payday for the subbie and bonus for the lads .

Fast forward 20 years and the fecking idiots are filling them up with foam , bridging the cavity and allowing moisture to transfer into the building . I never let them anywhere near mine , its going to be a big problem for many that did .