Kingspan in the loft

[meastwood98]

Hi,

Im thinking of getting some Kingspan Insulation boards and putting them between my roof beams. I currently have 4 inch of fibre glass insulation between my up stairs ceiling and loft floor boards (I couldn't use thicker as I wanted to board the loft for storage) and basically my house doesn't stay warm for very long after the heating goes off.

I have a few questions regarding putting kingspan between my roof beams: -

Is it worth doing or will it just make my loft warmer but not the rest of the house (only use loft for storage)?

Is there a chance if my roof leaked without me knowing, the beams could rot as they wouldn't have as much air around them?

Also, I'm planning on holding them in with pieces of timber rather than plasterboard as I only use the loft for storage so appearance is not important. Any problems with doing this?

Any information would be greatly appriciated.

Thanks

 

[freddiemercurystwin]

If your loft is vented as it should be then adding insulation in the rafter zone will be a complete waste of time. The proper solution is to build up the floor to allow more insulation. You will find hundreds of threads explaining how to do this in the Floors section of the forum.

 

[meastwood98]

Ok, thanks for the reply but please could you give more information. Why should my loft be vented? I've had a look and can't see any obvious vents. what about people that have loft conversions and use kingspan, there lofts are obviously not vented?

 

[freddiemercurystwin]

If the loft is not vented condensation will occur and the timbers will rot. You probably do have ventilation already, there will likely be an air gap at the eaves where you cannot easily see. If you do not have any existing ventilation though you ought to fit some retrospectively or you may get serious problems. Loft conversions retain their ventilation between the insulation and the tiles.

 

[wreckedit]

I have found that loft insulation even if it's higher than the ceiling joists will compact down with a board on it. It does in time sink of it's own accord anyway. So, any pressure on the ceiling diminishes. After fitting the boards and putting some old carpet on them will make insulating the roof beams a waste of time and money.