Insulation of sub floor

[JohnD]

The heat loss from floorboards is mostly draughts leading to cold feet, there is no convection loss and not much conduction or radiation.

IMO mineral wool is more suitable because it will squash to fill irregular gaps, especially round the edges of the room where cold air and black dirt blow up under the skirting and stain carpets. It is also non-flammable and cheaper.

 

[JohnD]

BTW I often use tilers batten, which is cheap and very similar to Jonbey's trellis poles.

 

[Steveb21]

Thanks.

I think I will look at getting the dormer area insulated to start off with and then move on to the cavity walls.

Although I would like to get rid of the constant cold feed so subfloor insulation will also be on the list.

If still draughty would having the windows done after the cavity walls have been filled cause issues? I am imagining a load of beads pouring out.

 

[Steveb21]

Might be eligible for CWI and RoomInRoom grant... so will look into this further.

 

[JohnD]

I am imagining a load of beads pouring out.

I don't think people use those old beads any more.

There is a system using sticky beads, that glue themselves together over time.

But AFAIK it's usually blown mineral fibre.