Hardwood Flooring Staples

[brnhornt]

Hey gang.  Quick question for the group.  I've put down a handful of hardwood floors successfully, but it's always been over plywood subflooring.  I'm helping a friend out by adding/extending existing hardwood flooring from a living room into her kitchen.  The subfloor is hardwood boards set 45 degrees to the floor joists.  The existing floor in the house has been there for decades, so I know the subfloor is sufficient, but I'm wondering if I can still use air nailed staples as the fasteners, or since it's a solid wood subfloor, I'm forced to use flooring nails instead?  Thanks!

[sleepy hollow]

FWIW.

Here is something I found online at Fine Homebuilding.  This is a question from a reader apparently:

We will be installing engineered wood flooring over an old tongue-and-groove plank subfloor. The subfloor is in good condition, but we are thinking of putting plywood over it before installing the flooring. Is 1⁄4-in.-thick plywood okay, or do we need something thicker? And should we use rosin paper between the plywood and subfloor?

—DAVID via FHB.com

[b]Rudy Kelosky, owner of Wood Floor Designs, Inc., responds:[/b]Depending on the condition of the subfloor, you may not need the plywood at all. Solid-board subflooring should be 3⁄4-in. by 51⁄2-in. group 1 dense softwood such as Douglas fir or larch.
Check the current subfloor for flatness, protruding fasteners, and squeaks, and reattach any loose boards. If the board subfloor is in poor condition, use plywood as a clean, flat surface to glue down 1⁄2-in.-thick engineered flooring. If the subflooring is in good shape, nail it down without the plywood, assuming the engineered wood is of good quality and 1⁄2-in. thickness or more.
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If the current subfloor has tongue-and-groove hardwood planks, check to see if it is attached directly to the joists or if it’s on top of another subfloor. If it is attached to the joists, you can use the 1⁄4-in. plywood to establish a flat surface and separate the two hardwood surfaces to avoid the expansion and contraction differences between the two hardwoods. If it’s on top of another subfloor, remove the tongue-and-groove hardwood to get down to the lowest subfloor level. Check for squeaks and flatness, and install plywood if needed.
As for the rosin paper, it may help with squeaks between the subfloors, but you are better off addressing the root cause, which is proper installation of subfloor and hardwood. Follow the manufacturer installation recommendations, and inspect the subfloor and fix the squeaks before installing the flooring. It is best to use #15 felt paper as a moisture barrier between the subfloor and hardwood if nailing down, or between the subfloors if gluing.

[brnhornt]

FWIW.

Here is something I found online at Fine Homebuilding.  This is a question from a reader apparently:
......

Yep, that's exactly what I'm dealing with.  Already added screws to each board at every joist crossing, and gonna use roofing felt, but just wasn't sure if solid wood and plywood would have the same holding effect with staples.  I threw an email out to the company where I buy my finishing supplies and got a response:

"This is Sean from City Floor Supply, I read over your question about your fasteners, and wanted to let you know that there are no issues with using staples in your situation. As long as the staples have enough length to penetrate the subfloor and they are a strong enough gauge for installing hardwood (i.e. 15.5 gauge-18 gauge), you will be fine to install over your pre-exsisting(sic) subfloor. "

So staples it shall be.  Thanks again sleepy hallow.
Kevin

[MstrCarpenter]

I have the Bostitch (mallet operated) pneumatic stapler. I use it for un-finished, pre-finished and plywood strip flooring. The only times I've switched to T-nails or cleats is when the staples failed to drive correctly frequently. I have also noticed fewer issues with the Bostitch brand staples. Other brands often have more jamming and/or crushed (distorted crown after driven) even though they are identical in size and wire thickness. I guess they're just not as hard.