Home>Discussions>INTERIORS>Molding & Carpentry>Filling a BIG hole in my subfloor
3 posts / 0 new
Last post
Filling a BIG hole in my subfloor

I'm slowly reflooring my house with hardwood, and ripped up one room's carpet last night. Much to my surprise, I found a rather sizable hole underneath the carpet that they just carpeted right over. I have a pretty cool, moist crawl space, so I'd rather not just lay down the builder's felt and floor over the hole; I don't think it would be a good idea to expose the hardwood directly to the crawl space.

I need some ideas on how to fill this hole well. Is there some kind of insulation foam I can just spray in, for example?

Apparently I can't post links or images (and the attachment upload thing breaks on every image file I try to upload), so you'll have to piece this URL back together. Copy and paste this into a new browser window: cl.ly/5QQD

Re: Filling a BIG hole in my subfloor

this type of repair is a must for a hardwood floor because you need the subfloor to nail to

not a big deal though, simply cut back the subfloor on the centre of the joist to each side of the hole, from there get a peice of plywood that matches the thickness of the boards or plywood and cut it to fit the hole. from there you need nothing more than to install blocks between the joist on each end of hte opening then glue and screw down the new patch

Re: Filling a BIG hole in my subfloor

I agree with the previous post regarding cutting a square to the joist and filling in with the same depth material.

I had a similar situation with the transition from our old home to the new addition. I had two vents holes I need to cover and had to match 3/4" plywood from the old part of the house, to the new addition, which has 3/4" OSB. I made a simple, but nasty patch which created a couple humps when I installed the new 3/4" hardwood flooring.

If I were to do this again, I'd make sure the two sub-floors matched evenly. I should have stopped laying flooring once I noticed the imperfection. I should have sanded down the areas or filled in the un-even spaces. I did layer scraps of roof felt in other areas that weren't even, and filling in the gaps worked well.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.