Semi roof & new extension retiled

[Basecoat]

Hi All

Back again for help. I have had my semi & new extension roof retiled. In removing the old tiles and battons my loft is one big mess. It's got to be cleaned out and new insulation installed. What is the best way to tackle this. What insulation should be used. I understand there is now "U" value to take into account. What is "U" value.

Would it be possible to insulate the gaps between rafters. I have had a velux sky light fitted. I have planned to do loft up and use it as a study. All advice will be highly appreciated.

 

[noseall]

you require a total of 280mm of quilt type insulation across and between the ceiling joists. we tend to fit 150mm between joists then another 150mm across the joists.

fitting between rafters however is a different ball game.

if you wish to utilize the loft space and satisfy building control, then you need to, beef up the floor joists, fit celotex or kingspan between rafters leaving an air gap, and underdraw the rafters with another layer of rigid insulation also.

between rafters will need to be 90mm and 25mm across with plasterboard and vapour control. plasterboard will need to be foil backed.

....or, you could remove the roof tiles, felt and lathe and build a warm deck roof cutting out the need for air gaps and vapour control.