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i have to say that a few times, i've run T/E in the dwarf wall, sitting atop the insulation. it's supported: current demand is very low, so derating is no problem; it won't get damaged as the only work being done near it is fixing the pvc frames. can't see a problem. and if rats etc. do get to it. then it's been badly built in the first place.
 
I sort of agree , but I would rather have a bit more protection than just PVC/pvc . Agree with demand,the most your gona to have is a tv + dvd player and a table lamp,will always ask just in case he wants to weld in his conservitry lol
 
totally agree with Eng54 , glad someone has at last given a real world view.
i dont see why pyro or swa is suggested as the only appropriate cable types for sticking in a cavity ??
none of their unique properties are needed for a few metres inbetween walls.
its probably the most impact and fire free area of any property.
and as for transmitting damp between the 2 skins , lol , no chance.
 
just need to make sure that you evict the cable munching fairies from the cavity first.
 
So what are the ties doing then?? Let alone the dollops of mortar that gets dropped in/down the cavity of just about every brick/block built building ever constructed... Or even, what about the insulation sheets come to that??

The ties should slope from the inner leaf of the wall to the outer to wick moisture to the outside. They should also have 'drip bends' in them to cause the moisture to bead up and drop.

There shouldn't be any dollops of mortar in the cavity as the inner faces of the brick and block should be cleared as each course goes up.

The insulation sheets should be held to the inner leaf of the wall using plastic clips over the ties. This prevents bridging and allows air movement in the cavity to reduce condensation.

All this of course is according to the building regs, but I suppose any of the trades can choose which bits they want to follow and which they don't?
 
If the regs state it why not implement it rather than going against the grain,not saying I would use swa or mi that's going too far , sling in a bit of conduit happy days or a lesser version of swa sorted jobs a good one
 
The ties should slope from the inner leaf of the wall to the outer to wick moisture to the outside. They should also have 'drip bends' in them to cause the moisture to bead up and drop.

There shouldn't be any dollops of mortar in the cavity as the inner faces of the brick and block should be cleared as each course goes up.

The insulation sheets should be held to the inner leaf of the wall using plastic clips over the ties. This prevents bridging and allows air movement in the cavity to reduce condensation.

All this of course is according to the building regs, but I suppose any of the trades can choose which bits they want to follow and which they don't?

I think we both know, as well as everyone else, that none of these things are adhered too!! 50% of those wall ties would be installed upside down anyway. You can't really avoid dropping mortar between the courses, you can only clear some of it as you go. Haha, never seen any clips holding those insulation sheets to the inner wall. So how do they hold the insulation balls and flakes in place then, that can be retro injected into these cavities spaces??
 
Absolutely, I doubt you'd find 5% of walls built to the regs in those respects. However they are the regs, and by running cables along the cavity either vertically or horizontally the regs wouldn't be followed for that reason.

It's one of those areas where common sense applies. So for example the cable running through at the top of a dwarf wall 500 -600mm high would cause no more issues than the lower face of the timber or plastic which closes the top of the cavity.

My point being ignorance of the regs, or ignoring the regs, is unacceptable. Choosing an unusual method is perfectly acceptable as long as the person doing so knows why a specific reg has the requirements that it does, and that their chosen departure/alternative can be shown to be as effective or better.

Balls, flakes, fibres and foams aren't covered by the current regs other than to exclude them from use when building to current regs.
 
compared to 50 years ago, houses today are thrown up. they may be built to hold a bit more precious heat inside, but i challenge you to come up with 0ne improvement other than that, over a hose built entirely with bricks and real wood (none of this thermalite dust crap, and chipboard, mdf, roof trusses that totally bar access to lofts, dry lining cardboard that won't take a fixing........ etc.etc.
 
I accept the challenge :)

Cinder blocks which were used prolifically in the '40s '50s and '60s are no longer allowed. They were just as crumbly as the modern thermal blocks, and they also started to burn if the building caught fire because they were essentially compressed cinders from the coking plants.
 
Challenge aside, I do agree with you. Modern construction techniques mean that buildings have built in obsolescense, and I don't think thermal efficiency is the reason. If a building lasts for a hundred years it's bad for all the industries involved in putting it up. If it lasts for thirty or so there is a turn around which keeps everyone in business/work.
 
I accept the challenge :)

Cinder blocks which were used prolifically in the '40s '50s and '60s are no longer allowed. They were just as crumbly as the modern thermal blocks, and they also started to burn if the building caught fire because they were essentially compressed cinders from the coking plants.

I bet those houses built with those cinder blocks will outlast anything built from the 70's onwards. Most of the council houses, and probably the low rise flats were built with them. Those in my parents house (built in 51) where i grew up, were pretty dam solid, as were the bricks that were used...
 
I bet those houses built with those cinder blocks will outlast anything built from the 70's onwards. Most of the council houses, and probably the low rise flats were built with them. Those in my parents house (built in 51) where i grew up, were pretty dam solid, as were the bricks that were used...

Which is just like saying that an old rewireable fuse board will outlast a modern board. It's true, but misses the point.
 
I sort of agree , but I would rather have a bit more protection than just PVC/pvc . Agree with demand,the most your gona to have is a tv + dvd player and a table lamp,will always ask just in case he wants to weld in his conservitry lol

I know several people who don't have central heating in their conservatory, just plug in a 3kw fan heater when it gets cold.
 
Neither the cinder blocks, nor the old style rewireable fuse boards are as safe as their modern counterparts.

Totally agree. Longevity is no substitute for improvement in safety. Give me an RCD board any day over one with only rewireable fuses. That said, I reckon the new crabtree stuff will be around for a good while yet. Just like me...robust, yet safe :)
 
Neither the cinder blocks, nor the old style rewireable fuse boards are as safe as their modern counterparts.

What are you saying, literary 100's upon 100's of thousands of Council homes are unsafe, because of the use of the old cinder blocks, ...that's just cobblers!!! I'd like to see any of these modern wooden framed houses and buildings withstand a house fire better than those old council homes....

As far as the electrical argument goes, for sure RCD protection is better to have than not have, the same goes for MCB protection over rewireable fuses...
 

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