Loft insulation - what to do about some cables?
- Thread starter Patroller
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Hmmm
Patroller does neat work, however in the photo it looks like you have taken the insulation right into the eaves.
If you have , then you have very likely blocked the vents which are provided to ventilate the loft area and prevent any build-up of moisture/condensation.
Patroller does neat work, however in the photo it looks like you have taken the insulation right into the eaves.
If you have , then you have very likely blocked the vents which are provided to ventilate the loft area and prevent any build-up of moisture/condensation.
good spot, mointainwalker.
I would also be thinking of increasing the depth of insulation, the recommended depth is 270mm
I would also be thinking of increasing the depth of insulation, the recommended depth is 270mm
Thanks both. Dont worry, I have a huge overhang at the front of the house (pictured) and there is over a foot of ventilation that side. The other sides all have plenty too. I dont have any felt under the tiles so loads of ventilation there too.
As for needing more insulation, there is already 270mm there! What you can see is the second layer (170mm). The first layer (100mm) is between the joists.
As for needing more insulation, there is already 270mm there! What you can see is the second layer (170mm). The first layer (100mm) is between the joists.
Sound like you have done a good job then, may I offer you my congratulations.
Hope you looked after the cables
Hope you looked after the cables
I think you can just about make one of them out on that picture, but overall they didnt lend themselves to laying ontop of the insulation. I suppose, in theory, I could rewire the whole lot.....!
They have been buried under piles of rubbish, including felt, for decades. Most of it is now on top of the first layer of insulation. Some of it is therefore under the top layer now.
They have been buried under piles of rubbish, including felt, for decades. Most of it is now on top of the first layer of insulation. Some of it is therefore under the top layer now.
mmmmm........ 
Don't wish to go over old ground.
But are these cables are a suitable CSA (cross sectional area) for the environment?
Taking in to consideration your original post's question and what has been posted earlier, regarding dissipation of heat from power circuits, the cables method of installation, current carrying capacity and the rating of the protective devices (fuse/MCB/RCBO) and derating factors of cable in thermal insulation.
or was the only problem area, above the utilities, which you have done as posted previously?
If so a picture of that would be more relavent to the thread
Don't wish to go over old ground.
But are these cables are a suitable CSA (cross sectional area) for the environment?
Taking in to consideration your original post's question and what has been posted earlier, regarding dissipation of heat from power circuits, the cables method of installation, current carrying capacity and the rating of the protective devices (fuse/MCB/RCBO) and derating factors of cable in thermal insulation.
or was the only problem area, above the utilities, which you have done as posted previously?
If so a picture of that would be more relavent to the thread
I apologize, maybe a bit confused with other comments made by others posts.
The questionis really regarding your power circuits, the lighting circuits should be fine but any power circuits buried in the insulation will have a cable derating factor, that will mean it is potentailly dangerous.
Like I said old ground.
So the question in simple terms is
You have not buried these cables without consideration of the cables current carrying capacity being reduce have you?
Only some of the cables have been buried, and no significant parts of any big cables such as the electric shower.
When I say 'buried', I mean some parts of them have a bit of insulation over them as opposed to a mountain of old felt and decades worth of dust and dirt etc.... so the term 're-buried' may be better!
When I say 'buried', I mean some parts of them have a bit of insulation over them as opposed to a mountain of old felt and decades worth of dust and dirt etc.... so the term 're-buried' may be better!
To be honest, I would be concerned if any cables other than that of a standard lighting circuit protected by a 5/6A protective devices, were buried or partially buried within thermal insulation. regardless of the fact they have in a previous life been covered in dirt and old felt.
I can't tell you of any derating factor that can be applied for cables covered by old felt and dirt or even the fire risk.
But I can inform you of the requirements and the best methods of installation/design when cables are buried within thermal insulation and the guidelines, recommendations of the safest way to prevent the risk of fire, according to BS7671:2008.
I can only stress how important it is to prevent this risk, not only to you, your family, your property, any pets or animals you may keep but that of your neighbours safety too, their family, their pets etc....
So just don't assume that because it was okay buried by felt, that the same will apply to thermal insulation, they are two different types of material and serve different purposes, so please be careful.
I can't tell you of any derating factor that can be applied for cables covered by old felt and dirt or even the fire risk.
But I can inform you of the requirements and the best methods of installation/design when cables are buried within thermal insulation and the guidelines, recommendations of the safest way to prevent the risk of fire, according to BS7671:2008.
I can only stress how important it is to prevent this risk, not only to you, your family, your property, any pets or animals you may keep but that of your neighbours safety too, their family, their pets etc....
So just don't assume that because it was okay buried by felt, that the same will apply to thermal insulation, they are two different types of material and serve different purposes, so please be careful.
The vast majority of the cables are on the lighting circuit. The only place where there are a few power cables thrown in is above the bathroom and (because of this) the insulation is 'bitty' as you cant just lay a big roll down without having to go under or around cabling.
But as you have mentioned all of the above I will give it the once over when I'm next in the loft to check everything is the best it can be!
But as you have mentioned all of the above I will give it the once over when I'm next in the loft to check everything is the best it can be!
Nice one and don't leave it to long.
PS buried or slightly buried does not make a difference, the term should really be totally surrounded.
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