wood framing-screws or nails? - DIY Chatroom

ron0805 · 10-13-2009, 05:27 PM

wood framing wats the best to use ? screws or nails and what kind?

NailedIt · 10-13-2009, 08:15 PM

As a framer (rough framing carpenter) and remodeler, and a DIY'er after all that, I prefer nails. Screws are better for certain tasks, but nails are easier to work with IMO. Framing with a quality framing nailer and an adequate air supply is multiples of times faster than screwing could ever be and you won't get stripped heads or curse the day of your birth trying to get two pieces to align and stay aligned. Of course, you could predrill everything... I even prefer hand driven nails over screwing framing together. I use screws for floor decking, stair treads, installing window/doors, etc... For actual "framing" of walls, ceilings, roofs, etc... nails are the way to go.

For general framing I use 10d or .131x3" full-round-head stick nails, or 12d coated sinkers for hand driven nails.

Screws are more versatile than nails, but for framing you want the specialist, not the jack of all trades.

bob22 · 10-13-2009, 08:58 PM

Aren't nails also stronger at shear and tensile strength than most screw types when framing?

GBR in WA · 10-13-2009, 09:04 PM

NAILING SCHEDULE - 1994 UBC TABLE 23-I-Q

Excerpts from the 1994 Uniform Building Code TM, copyright © 1994, are included in this guide with the permission of the publisher, the International Conference of Building Officials.
CONNECTION NAILING

1. Joist to sill or girder, toenail 3-8d (1) 2. Bridging to joist, toenail each end 2-8d 3. 1" x 6" (25 mm x 152 mm) subfloor
or less to each joist, face nail 2-8d 4. Wider than 1" x 6" (25 mm x 152 mm)
subfloor to each joist, face nail 3-8d 5. 2" (51 mm) subfloor to joist or
girder, blind and face nail 2-16d 6. Sole plate to joist or blocking,
typical face nail
Sole plate to joist or blocking
at braced wall panels
16d @ 16" (406 mm) o.c.

3-16d per 16" (406 mm) o.c. 7. Top plate to stud, end nail 2-16d 8. Stud to sole plate 4-8d toenail, or
2-16d end nail 9. Doubled studs, face nail 16d @ 24" (610 mm) o.c. 10. Doubled top plates, typical
face nail

Double top plates, lap splice
16d @ 16" (406 mm) o.c.

8-16d 11. Blocking between joists or rafters
to top plate, toenail 3-8d 12. Rim joist to top plate, toenail 8d @ 6" (152 mm) o.c. 13. Top plates, laps and intersections,
face nail
2-16d 14. Continuous header, two pieces 16d at 16" (406 mm) o.c.
along each edge. 15. Ceiling joists to plate, toenail 3-8d 16. Continuous header to stud, toenail 4-8d 17. Ceiling joists, laps over
partitions, face nail
3-16d 18.Ceiling joists to parallel
rafters, face nail
3-16d 19.Rafter to plate, toenail 3-8d 20. 1" (25 mm) brace to each stud
and plate, face nail
2-8d 21. 1" x 8" (25 mm x 203 mm) sheathing
or less to each bearing, face nail
2-8d 22. Wider than 1" x 8" (25 mm x 203 mm)
sheathing to each bearing, face nail
3-8d 23. Built-up corner studs 16d @ 24" (610 mm)o.c. 24. Built-up girder and beams 20d @ 32" (813 mm)o.c. at top
and bottom and staggered,
2-20d at ends and at each
splice. 25. 2" (51 mm) planks 2-16d at each bearing 26. Wood structural panels and particleboard: (2)

Subfloor, roof and wall sheathing (to framing):
(1 inch = 25.4 mm)

1/2" and less
19/32" - 3/4"
7/8" - 1"
1 1/8" - 1 1/4"

Combination subfloor-underlayment (to framing):
(1 inch = 25.4 mm)

3/4" and less
7/8" - 1"
1 1/8" - 1 1/4"

6d (3)
8d (4) or 6d (5)
8d (3)
10d (4) or 8d (5)

6d (5)
8d (5)
10d (4) or 8d (5)
27. Panel siding (to framing):
1/2" (13 mm) or less
5/8" (16 mm)
6d (6)
8d (6) 28. Fiberboard sheathing: (7)

1/2" (13 mm) thickness

25/32" (20 mm) thickness

No. 11 ga. (8)
6d (4)
No. 16 ga. (9)

No. 11 ga. (8)
8d (4)
No. 16 ga.(9) 29. Interior paneling
1/4" thickness
3/8" thickness
6d (10)
8d (11)

1. Common or box nails may be used except where otherwise stated.
2. Nails spaced at 6 inches (152 mm) on center at edges, 12 inches (305 mm) at intermediate supports except 6 inches (152 mm) at all supports where spans are 48 inches (1219 mm) or more. For nailing of wood structural panel and particleboard diaphragms and shear walls, refer to Section 2314.3. Nails for wall sheathing may be common, box or casing.
3. Common or deformed shank.
4. Common.
5. Deformed shank.
6. Corrosion-resistant siding and casing nails conforming to the requirements of Section 2325.1.
7. Fasteners spaced 3 inches (76 mm) on center at exterior edges and 6 inches (152 mm) on center at intermediate supports.
8. Corrosion-resistant roofing nails with 7/16"-diameter-head (11 mm) and 1 1/2-inch (38 mm) length for 1/2-inch (13 mm) sheathing and 1 3/4-inch (44 mm) for 25/32-inch (20 mm) sheathing conforming to the requirements of Section 2325.1.
9. Corrosion-resistant staples with 7/16-inch (11 mm) crown and 1 1/8-inch (29 mm) length for 1/2-inch (13 mm) sheathing and 1 1/2-inch (38 mm) length for 25/32-inch (20 mm) sheathing conforming to the requirements of Section 2325.1.
10. Panel supports at 16 inches (406 mm) [20 inches (508 mm) if strength axis in the long direction of the panel, unless otherwise marked]. Casing or finish nails spaced 6 inches (152 mm) on panel edges, 12 inches (305 mm) at intermediate supports.
11. Panel supports at 24 inches (610 mm). Casing or finish nails spaced 6 inches (152 mm) on panel edges, 12 inches (305 mm) at intermediate edges.

An old table, but answers your questions. Screws on sub-floor decking, exterior decking, metal framing, Simpson hardware, and drywall, though nails can be used on all but metal framing. Screws do not have the shear strength that nails do, that's why they are not in the framing lumber connections above.
Be safe, Gary

rselectric1 · 10-13-2009, 09:30 PM

I sure see the word "nail" in that code alot.

vsheetz · 10-13-2009, 11:11 PM

Also I suggest to buy a how-to book on framing

NailedIt · 10-14-2009, 12:21 AM

That's the table you pull out when your framer buddy insists you have to use 16d nails for all framing connections. There was another recent post where the OP referenced a connection as "just" being toe-nailed. Toe nails are capital "S" strong. For illustration, I often toe-nail rafters even when it's possible to face nail, or I do both so the connection stays tight. When you say lateral or shear strength in reference to screws vs. nails for framing, you're talking about screws simply breaking, as in snapping in two... Or more often you can directly observe the heads spinning right off as you get a screw just snug in a hard board.

Daniel Holzman · 10-14-2009, 12:51 AM

The question of nails vs. screws is a lot more complex than it is often presented. The two are really quite different in terms of how they work. A nail acquires its pull out strength entirely from friction with the wood, hence is subject to loss of pull out strength if the wood shrinks, which is common if the framing was at a high moisture content when installed (i.e. green). A screw maintains its pull out strength based on a mechanical link with the wood, so will typically lose only a small fraction of its pull out strength compared to a nail if the wood shrinks.

Nnail shear strength is a function of the shank diameter, whereas for a screw the shear strength is a function of the root diameter. This means that you have to be very careful when selecting a screw to insure that it has adequate shear resistance for your application.

There are other issues with screws that are more subtle. For one thing, if you do not predrill them, it is impossible to draw two boards together. In other words, if the boards start separated, they stay separated, unless you overdrill the first board. Since overdrilling is a lot of work, screws are often used incorrectly, and get blamed for poor performance when the real issue is improper installation. Additionally, some screws use relatively brittle steel, which is prone to torsional failure during installation. Since a nail is driven rather than rotated, it is not going to fail in torsion, but rather in bending, so again, failure to predrill can lead to twisting the head off the screw, which can lead the installer to complain about poor performance when really it is improper installation. Remember, the screw loses strength when it is installed without predrilling, but as I said, predrilling is such a pain that many people don't do it, and complain when the screw breaks.

So far as I can tell, there are numerous nailing schedules, including one in the MA building code that I am familiar with, but no schedules for equivalent screws. The Simpson catalog of hangars includes a variety of equivalent tables allowing you to use either Simpson nails or Simpson screws, but not for all their hangars, and not under all conditions. That said, a professional engineer can stamp framing plans and include a table of screws if they so choose, at least under MA building code.

As for advantages of screws, they have outstanding pull out resistance when correctly installed, which gives them great advantages when used for roof plywood installation in high wind areas. This is also true for plywood installation as sheathing on houses. For general framing, I prefer nails, but then again I generally lean towards use of Simpson or equivalent connectors with approved nails. The additional cost of the hangars is more than offset in my opinion by the superior connections they enable, which will probably make no difference under most conditions, but will make a big difference if your house framing is subject to a hurricane, tornado, or other extreme event.

Wildie · 10-16-2009, 12:20 AM

As an amateur, I prefer to use screws for interior walls that do not have any loads to contend with.
For the amount of work that I do in this regard, a nailer (would be nice) isn't justified!