Super Quilt Multifoil Insulation - Anyone used it in an already boarded out loft where the house has recently been re-roofed?

[Craig_S]

Hi All

I was wondering if anyone had a real world experience using Super Quilt Multifoil insulation. 

Let me give you a bit of background. 

Our roof was quite old and in the loft you could feel air movement and there was quite a bit of temperature change depending on what it was like outside. There is some fibreglass insulation between the joists and then flooring put on top of the joists. There was no insulation in between the rafters so I brought some Super Quilt Multifoil insulation I was going to put this over the rafters, inside the loft as I was told this would increase the insulation.

Unfortunately before I got a chance to put the Super Quilt up it was discovered there were some quite series issues with the roof so we had to have it re-roofed. 

Loft is a lot better now. Less temperature variation, though still some, what you would expect from a new roof without rafter insulation. There is the appropriate ventilation installed but there isn't the air movement that we had previously. I don't feel any. Also feels a lot dryer.

My intention is to still install the Super Quilt to the inside of the rafters to increase the insulation. My only concern is will condensation form between Super Quilt and the inside of the tiles as there is so much less air movement? 

I have spoken to the supplier and they have said as long as there's gaps at the bottom, where the rafters and joists meet it should be OK. 

I just wondered if anyone has done a similar sort of thing in a similar situation and how things are over time?

Thanks in advance for your help.

Let me know if you need anymore information.

[JohnMo]

A traditional roof is designed to be fully vented, so insulation above the ceiling only. Adding insulation to the underside of the roof will achieve nothing at best or worst lead to your rafters rotting as they will have no ventilation to drive of any accumulation of moisture. 

 

Your money would have been better spent adding more floor insulation to the loft