jgold723 wrote:
We are contemplating hardwood floors in an 1860 house we are
renovating. It currently has two layers (1.5 inches total) of pine
floor -- the rough-sawn subfloor covered by painted pine boards.
Everything sits on 2 x 8 joists (older style) set 30" OC.

I'm planning on tearing up the top layer of boards and putting down
3/4 T&G flooring (Advantech). But I'm worried that the amount of flex
(bounce) in the floor from the widely spaced joists will cause
problems down the road.

What's the dimensions of the present versus the proposed? Is it T&G or
simply butt seams? What about the thickness of each layer?

If the 1-1/2" is two 3/4" and the hardwood isn't some manufactured
product for which I have no information for on stiffness, hardwood such
as oak will be as, or stiffer than pine. If, otoh, the top level is 1"
and the underlayment is only 1/2" (which would be most unusual for the
age if it is original), then you would be removing material.

Unless the existing pine is in really bad shape, you might consider
simply refinishing it as being more in keeping w/ the age of the house.

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