Hi All…
We have a 16 x 46 addition with 3/4″ T&G OSB subfloor in place.
The height of the addition subfloor is 1 1/4″ below the height of the existing structure’s floor. We are going to finish floor over the whole shebang with laminate.
We already have enough 3/4″ OSB to lay over the addition floor – which leaves us 1/2″ shy of our target height.
My original intention was to rip up the 3/4″ existing pine flooring. However, that may be more invasive / expensive, than laying the layer of 3/4″ OSB, followed by another layer of 1/2″ OSB.
I guess my question is this… are there any problems with laying 3 (3?!) layers of OSB? Is there a better way to approach this problem? Perhaps 1/2″ nailers attached to the subfloor with the 3/4″ OSB on top?
Thanks guys!
and before you guys (you know which ones you are 🙂 ) chime in with “Why didn’t you set the floor height from the onset?”
It has to do with a log structure – the log ends and sill logs prevented proper height alignment to begin with.
Replies
You can use 1/2" sleepers to keep cost down, but you will have to deal with the hollow space generated between the sleepers - which may increase the cost. The hollow space will cause footsteps to sound loud and dif from the rest of the house. Be sure to run the sleepers perpendicular to the joists.
I don't know how your joists were designed to advise on the effect of additional layers of OSB.
F
You could put insulation between the sleepers and fill up the hollow space so footsteps don't 'drum' up echoes.
This would add a smidge of insulation, if it is over a crawl space or slab.
If the addition is over a room or basement, the insulation would help deaden some sound transfer.