When should screws be used for general wood framing?

Question

I was wondering what sort of fasteners are best for general Wood Framing? I understand that in general construction is done 100% with nails, but as a small time, diyer, I am looking for best practices.

My understanding is that general nails are superior for shearing forces, so must always be used in connecting floor joists and other similar applications.

While wood screws hold far better against force pulling them straight out (structural screws seem to be a thing as well, but are relatively rare and expensive).

Am I right in thinking that I should use screws for subfloor, top and bottom plates, etc. And nails for joists, gussets, headers, ect.?

As a commenter pointed out, we also have adhesive. Is their any reason not to use this liberally? I understand it is beneficial to add some when securing a subfloor. But I could use it on the ends of studs and under trusses to supplement hurricane clips, and between gussets, if too much rigidity was not a bad thing.

Answer 1

The short answer is that, for residential framing, the only situations that call for screws are:

• Where building hardware specifies screw fasteners
• Where squeaks are a concern and adhesive would be impractical
• Where access is limited with respect to hammers or air nailers
• Where the need for later non-destructive removal is expected

Everything else is usually done with appropriately-sized nails or staples, some of which should be adhesive-coated, ring-shanked, or otherwise special.

I won't endeavor to list all appropriate fasteners and their use-cases here, as that would be an inappropriately broad topic for this site. The most common pneumatic fasteners in my area are ~3" cement-coated framing nails, ~2-3/8" ring-shank nails, and 1-1/2" to 2" cement-coated narrow-crown staples.

Construction adhesive is appropriate for reducing noise and making structures feel more solid, as in staircases. It is not, however, rated for weather resistance scenarios. Mechanical fasteners and building hardware fills that role.

Answer 2

To answer your question, “What sort of fasteners are best for general Wood Framing?” I see that you capitalized “Wood Framing”, so I’ll concentrate on wood framing.

The Code stipulates the size, type and spacing for “wood framing”. It should be noted that this is a minimum requirement, but using a 20d spike when a 16d nail is required does not improve the fastening strength because it could split the framing and there would be no strength. Likewise, using a larger nail from a nail gun does not necessarily improve the fastening strength.

However, the Code does allow “Alternate Methods” with supporting data from a reputable agency...like ANSI.

Table 2304.10.1 from the ICC Code lists all required fasteners. I agree with @isherwood that it’s too numerous to mention all required fasteners, but here are a few you asked about:

1. Top plates: 8-16d @ 16” oc or 12-10d or 12-3”x 0.128” nails @ 12” oc

2. Ceiling joist to top plate: 3-8d common or 3-8d box ; each joist, toenail

3. Bottom plate to joists, rim joists, or blocking: 2-16d common or 3-16d box ; @16” oc

4. Stud to top or bottom plate: 2-16d common or 3-10d box ; end nail Or 4-8d common or 4-10 box ; toenail

5. 1/2” plywood subfloor: 6d or 8d common or deformed: 6” edges, 12” intermediate supports

6. 3/4” plywood subfloor: 8d common or 6d deformed; 6” edges and 12” intermediate supports.

Screws are acceptable if they meet the same length, diameter, etc. and have a testing agency’s report. (Like ANSI)

Screws and glue are especially useful when lumber tends to slide past other lumber materials, like underlayment past subfloor or subfloor past joists when walked on. (This is a prime cause of squeaky floors.)

Often, floor covering manufacturers will require a certain type and thickness of underlayment with specific fastening requirements, (i.e.: certain size screws at a certain spacing, etc.)