My title says it all. I need help and I am really happy this site exists.

Although I am pretty handy, this will be my first flooring job.

I have read several posts and have also read NOFMA's "Installing Hardwood Flooring" manual. I think I have a good plan, but would like to share it so that you all can confirm I am on the right track.

I have a bi-level home. I am looking to install Brazillian Walnut (IPE), purchased from******* in the family room and office (lower level - concrete slab). According to NOFMA's manual it seems, because my slab is at grade, I should do the following:

1. Prime and apply cold-type asphalt cut-back mastic
2. Lay down 15 lb asphalt paper (overlapping edges 2 - 4")
3. Put down another layer of asphalt mastic.
4. Put down another layer of asphalt paper
5. Lay down 3/4" plywood as a subfloor
6. Powder nail the subfloor to the concrete (nailing through the layers of asphalt paper and asphalt mastic).
7. Put more asphalt mastic over the plywood.
8. Lay down another layer of asphalt paper.
9. Lay down the planks.

Does this sound correct? If so, I have the following questions:

1. What is "cold-type asphalt cut-back mastic"? Can someone send me a link to a website? I'd like to make sure I buy the right stuff.

2. My subfloor (plywood) will be 3/4" thick. The powder nails I have 1 1/2" long. Is this long enough? According to the nail gun box, an Inch should go into the concrete. With my nails, only a 3/4" will go into the concrete? Ideally, I guess I should by 1 3/4" nails; however, I didn't see these in the store. Would a 2" powder nail be too much? That would drive 1 1/4 into the concrete... I don't want to ruin the concrete slab in any way and I also want to make sure the subfloor is secured. Sorry if this is a newbie question..

Quick responses would be greatly appreciated as it is crunch time (I'll be working on it today and the next couple of days).

* Note from moderator. I edited out the brand and url of the flooring. Please read Rules of the Board

Between #4 & #5 I add to my proceedure, a layer of 6-mil plastic


Henry's has Black mastic, in the roofing section, somewhere near the 15# asphalt impregnated felt.


I use Tapcons to anchor the decking.

Thanks for the reply. I just took a look at the "Tapcons". That looks like it would be quite a bit of work. Do you need to pre-drill for each hole? Also, will they countersink into the subfloor? Should I be concerned with using the powder nails? It does look like they would hold the sublooring better though.... I have been wondering how a strait nail (powder nail) would really work...

Just for clarification, I am planning to use the following tool --> http://www.tools-plus.com/ramset-hd22.h ... rm=RAMHD22

I use the powder actuated nails, and the floors that I've installed using them are performing great. I don't use the paper and mastic method though.

Instead I apply a vapor barrier/ anti-fracture membrane (Bostik's MVP works great but I've used others with equal sucess). Then I use PL400 around the edges and I zig-zag the middle before nailing it down with one and a half inch Hilti powder actuated nails. I used about 25 nails or so, starting in the middle and working out.

I use the Hilti gun that looks like, well a gun, but I suppose you could use the one you posted a picture of earlier. The 1 1/2" nails worked fine for me. I think I remember when I tried using a longer nail they didn't sink in all the way. But if you're using the paper and mastic method you may need the extra length.

Maybe someone here who installs over slabs more than I do can explain a better/different method.

Good Luck