I have one small area in a hall that I leveled using shingles. It turned out to be one 30 inch wide row of three shingles deep. I'm thinking of going back a ripping them out and leveling with wood. My concern is that the nails won't penetrate deeply enough through 3 shingles to anchor the hardwood. Are my concerns justified or will the hardwood nail down ok over 3 shingles?

thanks

Use longer and more fasteners in that area.

2 2/2 cleats are as long as my nailer shoots. I thought that was standard and about the max you could go.

thanks!

If the highest point of the shingles is 1/2" or under..your good to go, with that length fastener.

I measure it. It's 1/2 inch. That includes a thin layer of thin luan-like sub flooring over the top of the shingles.

What material is your subfloor, under the shingles & luan?

3/4 inch plywood.

That's great....you'll be fine. Iv'e installed many 3/4 solids using 1 1/2" fasteners. So the 2" will give you adequate penetration, and you'll get good "bite" into plywood.