help with wooden flooring please

[g1bby1]

Hi all,
I want to lift my carpet and expose the original wooden flooring. Instead of filling the gaps I would like to lift the flooring, fit an underlay across the joists (draught proofing) and possibly even fit undefloor heating.
1. Is this best practice
2. Whats the best products on the market
3. What type nails should I use to refit the original flooring

 

[stephenf8542]

If you try to lift the flooring you'll damage most of it as it'll have been ''secret nailed'' most likely.What kind of underlay were you thinking about?Underfloor heating needs to be fixed to a flat surface not joists.I think you'd be better with sand and fill

 

[masona]

The easiest would be to put 3mm hardboard sheets over the flooring with staple gun