Studio Floor Install - Do these guys really know what they're doing? ?

[Gorquin]

I'm getting estimates to have a wood floor installed over concrete, 6 mil plastic, 1/8" soft padding and 3/4" plywood(actually 2 layers of 3/8" ply laid perpendicular to each other).

 

Most contractors are non-specific when I ask what length of nail/staple they intend to use and one contractor told me he'd probably use 2" nails. I think half of these guys are guessing at what to use.

 

Here's my thinking. Using Pythagorean Theorem. A squared + B squared = C squared then if we assume that a nail will be driven in at a 45 degree angle then:

 

Side A = B for a 90 degree triangle.

A will = depth of the wood.

C will = length of nail/staple.

Now we have the flooring which is Solid 3/8" Oak Tongue and Groove. They will nail/staple in the groove which is 1/8" thick.

 

So we have ( (.75 (plywood) + .125 (1/8"flooring groove)) squared ) X 2 = 1.53 But that = C squared

 

1.53 Inv X squared on my calculator = 1.237"= C (length of nail/staple) That's < 1 1/4" nail/staple.

 

Thinking that some may nail/staple at an angle steeper than 45 degree means at most what they should be using is probably a 1" nail/staple. Any longer and they will penetrate the vapor barrier on the pad and the 6 mil plastic causing either a break in the concrete and/or a raised spot in the flooring if the nail/staple doesn't fully penetrate the concrete. If the nail/staple bends up the floor can't lay flat.

 

If they're installing a HW floor over a subfloor supported by wood beams then it won't matter because any excess just goes into the insulation but on concrete….you're bottoming out.

 

So, am I missing something, is my math wrong, or does my math work and some of these contractors don't know what they're doing?

 

Thanks….

 

 

[MikeRivers]

Nails at 45 degrees? Do they do that? I would use screws, lots of screws. Then it won't squeak.

[Gorquin]

Mike, screws might sound good but trying to use screws in a groove, seat it, and leave space to add the next board would be difficult at best. And very slow! LOL

 

What, no math pro's or engineers to check my theory?

[WRGKMC]

I think, you're over thinking the process. When they buy flooring like they simply buy the right nails for the pneumatic nail gun to do the job.

 

Unless you're dealing with real rookies, many contractors do that kind of work on a regular basis and select the right nails for the right job.

 

Here's the whole process including the specialized nail gun that drives the nails in at an angle.

 

http://www.diynetwork.com/how-to/how-to-install-a-hardwood-floor/index.html

 

[MikeRivers]

Mike, screws might sound good but trying to use screws in a groove, seat it, and leave space to add the next board would be difficult at best.

 

Oh, I didn't realize that you were using real tongue and groove flooring. The plywood threw me off. I thought that was your floor.

 

[philboking]

Is this in a basement? Wood can be a bad idea there... It isn't IF it will get wet, it's WHEN?

I had some recent flooding in Tangent Studio (after 11 years or dryness) and ended up tearing out about 11 yards of carpet. I plan to redo it in tile.

 

But, to address your question, tongue and groove flooring is designed to be nailed to a subfloor. Just nailing the floor boards together will simply cause splitting (in addition to the problems you mention).

[Gorquin]

The floors, two layers of 3/8" ply, will be stapled together so I'll have 3/4" of subfloor. The floor is in a Metal Building raised above grade with gutters, caulking, and foam insulation in addition to the 6 mil plastic and 1/8" padding that will be under the subfloor so moisture should not be a problem.

I agree the guys that know what they're doing come up with the right answers. I may be a bit overboard doing calculations but some of these guys have been doing this for years and still come up with the wrong answers. LOL

[MesaMonster]

The nail gun drives the nails at the proper angle and depth. Grant it, the nail guns can accomodate different size nails. The floor guys should know how long the nail should be.