(I know it's a bit late but) I'm thinking about insulating the ground
floor. Any comments? I'm thinking:
1. buy some of that stuff which comes as fairly rigid fibre slabs (3' by
14"?? -- we used it for our new extension loft, 15 years ago: can't
remember the name - much handier than glassfibre rolls)).
2. go under the floor, and strap this stuff up [somehow] between the
3. do I just "wall in" all the microbore CH pipes, electric cabling etc,
or should I take steps to protect them/leave them free?
4. This is a 1962-built semi-detached.
5. (I think I dare make it public here, and it may actually be
relevant): I turn 60 before long (I know, I know! Hard to believe, lads
but it's true :-< )
6. any other points? My main Q to this group is No.3 above.
The main object is to feel warmer: "paying for itself" is not so much of
a consideration. This does not mean I am rich: it means I'm sick of
feeling cold (and of shelling out my hard-earned to foreign energy
conglomerates who were handed our national energy industry a few years
Plastic garden netting is often recommended for this.
The electric cabling should not be covered in the insulating material as
the current carrying rating of the cable would be reduced. The pipes
should be well lagged under the floor anyhow so I don't think any extra
insulation around them would do any harm.
I'll have a go - I'm sure others will add more detail/corrections:
1. Slab or roll insulation sounds fine. Sounds like you have good
underfloor access, so blocking necessary air circulation shouldn't be
an issue. AIUI retrofit floor insulation is some way down the "most
benefit" priority list after tanks & pipework / ceiling & roof /
walls / windows & doors / other draft sources though.
2. You could try stapling netting/chicken wire to the underside of the
3. CH pipes should be lagged anyway, so extra won't do any harm.
Electrical cables need to dissipate heat, so they should remain as
they are. Pvc cabling shouldn't come into contact with polystyrene,
but sounds like you will use glass wool.
5. Repeat after me, "I'm a pensioner, gi'us a discount!"
As one who turned that some time ago, and who has had the same
problem.. IF you have room to fit under the void the problem is easy
Get either sheets of TP10 Kingspan or the equivalent 600 x 1200 x 50
smaller cavity wall or roof insulation board and nail it to the
underside of the joists using the stainless steel "nails" (square
twisted) and 2" round plastic washer/ fixings used by Kingspan to put
on the EXTERIOR insulation before rendering. This will hold it in
place and provide a continuous layer under the joists.
If no room to get under and nail then back to netting