Levelling old joisted wooden floor

[dddommm]

Hello,

I need to level a 100 year old floor in a 1st floor bedroom. We have established there is no structural issue, and the joists have just settled. I need to take up some boards and make sure there is no rot, but assuming not, I think I have a few options. I wanted to see what people here think.

I will be taking up the floorboards to reveal the joists and at the end replacing with floor ply (or any other good suggestions?), as it will be carpeted. I will then recycle the nice floorboards in a new kitchen extension downstairs. As far as I can see these are my options:

1) Shim the joists with cuts from joist length (ish) 2b4, glued and nailed down, remembering to account for difference in ply depth vs old board depth. Ply then nailed on top.

2) Sister the joists with 2b10, nicely level, remembering to account for difference in ply depth vs old board depth. Sistering with glue and nails. Ply then nailed on top.

3) Replace the joists with new 2b10 or similar with new joist hangers (beam situation dependent!). Ply then nailed on top.

4) Lay a new set of joists in between the old ones (leaving old in place), with new joist hangers (beam situation dependent). Ply then nailed on top.

What are your thoughts? And should I lay insulation while I am there (for both sound and heat)...even though its between floors I feel I should do it while I'm there!

Cheers

dom

 

[TheVictorian]

I would rip the floorboards up and then decide the best way to go depending on what you find.

Personally I would sister the joints using coach bolts rather than screws. I would then screw 22mm ply on top rather than nailing it.

Insulation is up to you, do you have a problem with sound travelling and is the bottom room cold and the top room too hot?

 

[dddommm]

I am liking the idea of coach bolts. Far more robust. Agree too on screwing...might take a bit longer but will make access much easier.

Any thoughts on frequency of the bolts along the joist? I am thinking every 16inches, slightly staggered top and bottom (1.5 inches from top/bottom).

 

[TheVictorian]

Sounds fine to me!