Best way of insulating down into the eaves?

[timski]

Hi Guys,

My house has a roof where the top rooms go up into the attic area slightly so the corners of the ceilings are slanted. I think they call them skeelings?

There is no insulation in between the ceiling and the tiles so it's really cold during the winter.

I tried insulating a small area by pushing 50mm celotex insulation board down into the eaves but I was surprised to find there doesn't appear to be any difference... at least not according to the Black and Decker heat/thermal leak detector I used. Same reading coming back from insulated section and non-insulated section. I've tested the detector on other areas where I would expect to see a difference and the detector itself appears to be working.

I think the problem is there is a small ridge (maybe a batten) half way down the eave which means I can only get 50mm celotex down into the eave above the ridge leaving a 40mm gap below the celotex. Ideally I guess the celotex would be against the ceiling and the gap above but that isn't possible due to the ridge. The rafters are 90mm. You can see this in the picture below.

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• timski
• 17 Oct 2014
• 1

Another option I had considered is pushing some mineral wool down into the eaves and using some kind of vent to keep a bit of a gap for ventilation but above the insulation so the gap of cold air isn't between the insulation and the ceiling but the insulation and the tiles.

I'd appreciate your advice.

Thanks,
Tim.

 

[catlad]

Your making hard work for yourself for little reward, my advice is to buy insulated plaster board as thick as possible and screw it to the underside of your ceiling joists/rafters or build a false ceiling.

 

[timski]

Your making hard work for yourself for little reward, my advice is to buy insulated plaster board as thick as possible and screw it to the underside of your ceiling joists/rafters or build a false ceiling.

Thanks Catlad, I think that is what I will do in the longer term when I've got the money and can afford the disruption. Every room upstairs in the house would need to be cleared and we've only recently moved in, are more or less still living out of boxes and are adjusting to having twin boys to deal with so maybe next year

I'm boarding the loft to make space so then we could do a room at a time but I thought improving the insulation in the eaves is something I could maybe do from within the loft space in the meantime?

Thanks,
Tim.

 

[timski]

I was thinking maybe something like the pic below would work but I can't find them for sale in the UK. I think they call them eave baffles.

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• timski
• 18 Oct 2014
• 1

Thanks,
Tim.

 

[catlad]

Never seen that stuff before but I have seen a lot of cavity walls filled and insulated with polestyrene balls, which you can buy in large bags generally sold as bean bag filling which you could pour down your voids.

 

[freddiemercurystwin]

They are quite common here and are what would be specified if this were a new build, they're called rafter vent trays https://www.google.co.uk/webhp?hl=en&gws_rd=ssl#hl=en-GB&q=rafter+vent+tray though retro-fitting them would be easier said than done.

 

[catlad]

I don't think he is after venting more insulating

 

[freddiemercurystwin]

He will need to retain the venting after he has shoved any insulation in the gap.

 

[catlad]

I can see the backs of his tiles so on this occasion I don't think its necessary.

 

[freddiemercurystwin]

Good call.

 

[timski]

That's right guys. There is no felt. Does that mean ventilation isn't an issue here?

Thanks,
Tim.

 

[catlad]

Any moisture that gets into your loft will be able to escape through the gaps between your tiles.