Loft insulation

[me]

I am having cavity walls insulated soon and the company recommended more loft insulation. It currently has the 4" thick old rockwool stuff from the

60's. Problem is most of the loft is boarded. If we were to increase depth of the insulation do I then have to add extra supports to allow me to re-lay the bords, or is there some other way to fix this? Is there a better insulation material that can be layed between rafters and provide a better insulation level, without increasing its depth? Thanks Paul

[Phil Anthropist]

They probably want to bring it up to 8 inches in which case I don't see how you can re-lay the boards on top of 8 inches of insulation without risking damage to bedroom ceilings. Can't they just upgrade the area that isn't boarded?

Phil

[Dave Fawthrop]

|I am having cavity walls insulated soon and the company recommended more |loft insulation. It currently has the 4" thick old rockwool stuff from the |60's. Problem is most of the loft is boarded. If we were to increase depth |of the insulation do I then have to add extra supports to allow me to re-lay |the bords, or is there some other way to fix this? Is there a better |insulation material that can be layed between rafters and provide a better |insulation level, without increasing its depth?

IME boards to store the junk in the loft are much more valuable to me than any extra insulation might ever be. The space under my boards is full of insulation, I just added more insulation, across the line of the rafters, on the unboarded areas.

The agenda of the salesman is to sell more product regardless of how much value the product is to you. He is probably generally correct about adding more loft insulation but will not take into account the value of the boards to you.

[Chris Bacon]

You can replace the old with better insulation, but (of course) it's more expensive. As you've got boards over4" of insulation, the value of the insulation will be a lot better than unconfined

4" insulation anyway. Is it worth it?

[mcbrien410]

If most joists are 7" x 2" , how do you fit 8" insulation? If you can easily lift the flooring, then re-insulate with Knauf RockWool Slab. There is 75mm and 100mm. thickness. You can carve it with a Bread knife. It is REALLY god at sound insulation. When you ut the loft flooring back USE SCREWS.

I did put the specs on this site some time back. Do a search in here for rockwool slab and/or Chris McBrien.

Regards Chris.

[Owain]

And junk has its own insulation value, of course.

Owain