Rafterloc Query

Southern Comfort

Can anyone tell me if the Rafterloc width of 565 mm is available in Ireland. Or is it only available here in 360 mm width?

Thanks.

Fergus

And while you guys are at it.. another question ..

The thicknesses available seem to be 75mm, 100mm, etc. If I preserve the 50mm ventilation gap with the roof, the 75mm rafterloc will be proud of the rafters on the underside by around 10mm. This will produce an air gap when a second layer of insulation is placed across. Is that a problem and if so how do you get around it? Thanks in advance.

tred

Fergus wrote: »

And while you guys are at it.. another question ..

The thicknesses available seem to be 75mm, 100mm, etc. If I preserve the 50mm ventilation gap with the roof, the 75mm rafterloc will be proud of the rafters on the underside by around 10mm. This will produce an air gap when a second layer of insulation is placed across. Is that a problem and if so how do you get around it? Thanks in advance.

I was about to put in a rafterloc type insulation, but after talking to about 5 experts stayed away, and went for another product..... To be honest its handy and everything, but its candidate for some minimum cold bridging, no matter how good u are with a saw, can u guarantee straight cuts laser like!.....

Fergus

tred wrote: »

I was about to put in a rafterloc type insulation, but after talking to about 5 experts stayed away, and went for another product..... To be honest its handy and everything, but its candidate for some minimum cold bridging, no matter how good u are with a saw, can u guarantee straight cuts laser like!.....

Can you explain exactly where you would envisage the cold bridging problem.

sydthebeat

tred wrote: »

I was about to put in a rafterloc type insulation, but after talking to about 5 experts stayed away, and went for another product..... To be honest its handy and everything, but its candidate for some minimum cold bridging, no matter how good u are with a saw, can u guarantee straight cuts laser like!.....

well the sales pitch of the rafterloc is that it is cut oversized, and is squashed accordion like between the rafters.... so the cuts do not have to be laser like

tred

sydthebeat wrote: »

well the sales pitch of the rafterloc is that it is cut oversized, and is squashed accordion like between the rafters.... so the cuts do not have to be laser like

I was all for it from the start, but having listened too a few guys,i just felt more comfortable with what i went for in the end. Even when i priced it of one vendor, he was advising me that it was the best product with regards to performance at the pitch of the roof. I must dig out the email and post on exactly what he said.

Southern Comfort

tred wrote: »

I was all for it from the start, but having listened too a few guys,i just felt more comfortable with what i went for in the end. Even when i priced it of one vendor, he was advising me that it was the best product with regards to performance at the pitch of the roof. I must dig out the email and post on exactly what he said.

Hi Tred. What did you go for in the end?

I'm now going for 100mm of Moy Metac (U value of 0.34), with a breathable membrane, above my attic's plasterboard ceiling.

I would have gone for Knauf Rafter Roll 32 (U value of 0.32) but I found it almost impossible to source it. We're removing the tiles and putting it in from the outside.

tred

Southern Comfort wrote: »

Hi Tred. What did you go for in the end?

I'm now going for 100mm of Moy Metac (U value of 0.34), with a breathable membrane, above my attic's plasterboard ceiling.

I would have gone for Knauf Rafter Roll 32 (U value of 0.32) but I found it almost impossible to source it. We're removing the tiles and putting it in from the outside.

150 metac. what made u change ?

Southern Comfort

Two reasons really.



1. My plasterboard ceiling isn't foil backed and a builder said I'd have a problem with dampness/condensation if I used Rafterloc.



2. My rafters aren't evenly spaced and it would be difficult for my man to cut it accurately. And it would take him much longer to do the job.



I'd love to be able to use 150mm of Metac but my rafters will only take 100mm. 100mm has a U value of 0.34 but 150mm has a U value of 0.23. http://idevelop.ie/iproducts/productinfo.php?Product=436&prodgroup=72&display=



That's pretty good!

Southern Comfort

Duplicate post......