insulating eves

jdpl28

hi,

I'm insulating the attic, but at the eves, the ceiling is sloaped. should i stuff insulation into these eves? or should i be worrying about ventalation? is there anything i can do about it? cause it seems like it's a big enough area to leave uninsulated?

thanks,
J

10-10-20

You will get some basic guidance from these spec sheets.

http://www.insulation.kingspan.com/ireland/k7.htm
See Product and Applications Details.
See pages 10 onwards.

You don't want to block the vents, you have to leave them open.

pullandbang

Get as much insulation into the joists without blocking the vents. You need to make sure the air can circulate. Mind you that in itself causes problems because you are ciculating cold air in from the outside and causing draughts which in turn causes more heat loss. Catch 22!

Try this www.smartrinsulations.com it might help.

gsxr1

jdpl28 wrote: »

hi,

I'm insulating the attic, but at the eves, the ceiling is sloaped. should i stuff insulation into these eves? or should i be worrying about ventalation? is there anything i can do about it? cause it seems like it's a big enough area to leave uninsulated?

thanks,
J

insulate between the joists(not rafters) . Then blanket over the insulation running it across the joists again with 150 mm insulation.

Do not push the insulation into the sofit. The insulation should not go beyond the wall plate that you roof seats on. a space should be kept clear so air can circulate . You need this for house and cavity ventalation . condensation prevention ect....

KAGY

jdpl28 wrote: »

hi,

I'm insulating the attic, but at the eves, the ceiling is sloaped. should i stuff insulation into these eves? or should i be worrying about ventalation? is there anything i can do about it? cause it seems like it's a big enough area to leave uninsulated?

thanks,
J

From the building regs (2002 are the last ones I have, haven't updated them after my house was built!)
I would suggest using foil lined rigid insulation, that way you get a higher U value than stuffing the space with fibreglass and you will keep the ventilation gap at the top.
I'm assuming that you will be just shoving it down from the attic rather than removing the plasterboard.

Part F2003 wrote:

2.2 The traditional method of limiting condensation in roof spaces is through the provision of adequate ventilation for cavities or attic spaces on the cold side of the roof insulation. Alternatively, where such cavities or spaces are absent, an effective vapour barrier is provided on the warm side of the insulation so that vapour from the building cannot permeate the insulation.

See attachments for pics

PART L 2002 DWELLINGS wrote:

Installation guidelines and precautions.
The insulation is installed in two layers, one between the rafters (and battens) and the second below and across them. To limit water vapour transfer and minimise condensation risks, a vapour control layer is required on the warm side of the insulation. No material of high vapour resistance, e.g. facing layer attached to insulation to facilitate fixing, should be included within the overall thickness of insulation.
Care must be taken to prevent roof timbers and access problems interfering with the continuity of insulation and vapour control layer.
Provision must be made for ventilation top and bottom of the 50mm ventilation gap on the cold side of the insulation.
Care should be taken to avoid thermal bridging at roof-wall junctions at eaves, gable walls and party walls.