Tiled floor over suspended floor - heating?

[David WE Roberts]

Hi,

we are planning (some time) to redo the back of the house as a single living area.

The existing floors are wooden suspended apart from the far end of the kitchen (used to be coal shed and out door toilet) which is solid.

We would like to put down tiles; ideally we would also like to have underfloor heating to keep the tiles nice and warm for bare feet.

Is this possible over a suspended floor or is the loading and/or extra depth required likely to be a problem?

TIA

Dave R

[Tim W]

Wot's a suspended floor?

Tim w

[The Natural Philosopher]

Yes, its very possible but you need to lift the wooden floor to lay it. and I am afraid if you want to heat the solid part, dig that out.

two things will need to be added. Stiffness so the tiles don't crack, and insulation so you don't lose all the heat downwards.

And probably a vapour barrier to protect the woodwork from damp assuming its cold below and ventilated.

If you can access the underside, then you may be able to lay pipes underneath and infill floor joists with insulating foam like celotex. If its wooden boarded above I strongly recommend you screw down a further layer of ply or chipboard to stiffen the floor, and install herringbone bracing between the joists to make the whole thing rigid as well.

Or simply lift the whole floor, and make an insulated screed floor in the void.

To put it simply, to achieve what you want is not going to be a quick DIY job, Its fairly major, requires thought, and comparative costing of various possible approaches. I do think it is well worth doing if you can afford it though.

[David WE Roberts]

Ummm....a floor that is suspended? On joists, over a void :-) This is the alternative to a solid floor.

Most floors other than ground floors are suspended (although I did once work on some 2nd World War era houses which were concrete everywhere - ground floor, stairs, first floor. I don't think the floor of the loft was concrete but I wouldn't have ruled it out).

AFAIK most modern (post 1940s?) houses have solid floors downstairs but most

1930s and older (by a few 10s of years) houses have suspended floors downstairs. At least, our house in Derbyshire built in 1896 has suspended floors.

Which reminds me of the terrace in Bingley where b&s-in-law lived. The ground floor kitchen was flagged over joists, so both solid and suspended. After some investigation it turned out that there was dry rot under the floor and the joists had been reduced to not much more than paper. They decided to remove the washing machine and cooker (spin drying with an uneven load was suddenly very unatractive) and we helped them remove the flags using a beam through the ground floor window as a make shift hoist to lift and move the flags. The only thing holding the floor up was the snug fit of the flags - still makes me twitch a bit when I think back!

Where was I? Oh, yes...Thursday.......mine's a pint, I think.........

[Tim W]

Thanks. I don't think I had ever heard the term.

Tim