Which screws to use for 2 x 4 construction?

[RobertMacy]

Went to add a structure to the studs and need to use screws to assemble [no real way to pound nails in and pounding would damage existing structure, so nails are OUT] BUT! vaguely remember some threads here regarding using readily available 'sheet rock' screws causing failures in a structure under load.

Thought I should ask the 'experts' here.

Can I use sheetrock screws if they are to be placed only in tension and never in shear mode? Or, is using sheetrock screws totally stupid? Are there readily available 'construction' screws from HD that are an all around better choice?

Problem is that I've had good personal experience using sheetrock screws in some other [albeit poorly assembled] construction [choice ofsheet-rock screws was a matter of convenience and they actually held better than nails]. The long term integrity of the structure didn't matter a great deal. All the structures came under heavy wind load the nails failed due to slight movement simply working the nails out. The screws themselves remained intact, but sometimes they stripped out of their holes and the structures failed, too.

However, during construction I did 'snap' a few screws off, reminding me they are a bit brittle. It's just I envision 'construction' screws being more 'rubbery' and less brittle.

Are screws simply screws and just go ahead? Is it all right to use sheetrock screws for a bit of construction? [interior, will have some loading.]

[Chip C]

If you're bothering to ask, then yes, save the drywall screws for drywall. They're a hard metal, I guess to withstand the abrasion (and maybe corrosiv eness?) of gypsum board, and (as you've found) correspondingly brittle. Dry wall is a light-to-moderate, very static load, and mostly in the compressiv e direction. If you're putting up shelves or cabinets, you're looking at po ssibly very heavy loads, probably all in shear, plus vibration and occasion al shock. Not what drywall screws were made for, even though we all have ha lf-full boxes kicking around.

For load-bearing work, find a general-purpose mild-steel screw long enough to get an inch (or more, if you know there's no wires) into the stud. You c an get decking and subfloor screws that work well; these countersink themse lves in soft wood and plywood. If you're going through holes in metal brack ets, then look for a round head, obviously. For electrical boxes, plumbing strapping, etc I keep a supply of #8 or #10 round-head screws around in 1/2 " to 1". For shelf brackets or a cabinet rail I'd use something longer and I'd probably use washers, too.

Now lets see what the *experts* say ...

Chip C Toronto

[nestork]

Also, friction is one of the least well understood phenomenon in the world. It takes less total work to zip a drywall screw in with a drywall gun spinning at 30,000 rpm than it does to wrist twist it in by hand or with a cordless drill turning slower. So, while it's not enough to be noticable, higher speeds will overcome friction better than slower speeds.

Deck screws where I live come with Robertson drive heads, and I find those vastly superior to Phillips or slot because you can apply way more torque to the screw head without the drive slipping or coming out of the screw head. Look around to see if you can buy Robertson drive deck screws where you live. In addition, a Robertson drive will jam into the screw head so that you can hold the screw upside down on your screw driver or cordless drill without the screw falling off. You can't do that with Phillips or slot.

[Dan Espen]

I used deck screws to put together a fence which was partially demolished by Sandy.

None of the screws broke. A few were pulled out, but mostly the lumber broke.

So, I think you'll be fine with deck screws.

[John Grabowski]

*I had a chat with a local building inspector about this several months ago. He said drywall screws are only to be used for drywall. Regular wood screws don't qualify for structural connections. Deck screws are for holding down boards. He told me that structural screws are acceptable as a substitute for nails. You could try calling your building inspector to see what is acceptable.

Simpson StrongTie makes structural screws of which Home Depot does stock some. They also have other structural screws from other manufacturers. You can also use some structural connectors to make things really strong. Home Depot carry's the screws for fastening the connectors as well.

[dadiOH]

Wood screws are readily available...McFeeley's has about anything you could ever want. Even HD/Lowes has a fair amount. Don't know if HD/Lowes carries square drive wood screws or not but that is way preferable to Phillips.

Besides tending toward brittleness, there are a couple other things about DW screws that tend to disqualify them. First of all, they are often #7 shank; for what you are doing I'd want #10, #8 minimally. Secondly is the head shape; this isn't a biggie but DW screws have a "bugle" head...concave on the under side. That is great for DW, less so for wood as there is less bearing surface. As I said, not a biggie especially for soft wood and I doubt you'll be counter sinking anyway.

[dadiOH]

Wood screws are readily available...McFeeley's has about anything you could ever want. Even HD/Lowes has a fair amount. Don't know if HD/Lowes carries square drive wood screws or not but that is way preferable to Phillips.

Besides tending toward brittleness, there are a couple other things about DW screws that tend to disqualify them. First of all, they are often #7 shank; for what you are doing I'd want #10, #8 minimally. Secondly is the head shape; this isn't a biggie but DW screws have a "bugle" head...concave on the under side. That is great for DW, less so for wood as there is less bearing surface. As I said, not a biggie especially for soft wood and I doubt you'll be counter sinking anyway.

[DerbyDad03]

These Star drive deck screws are also good for upside down and no slip driving.

There are different brands and they typically come with a driver bit in each box.

My DeWalt cordless has a clip for holding an extra bit. I keep a Star drive bit in the clip since just about every screw I use is either a #2 Phillips or Star drive. I always have a bit available whichever screw type I grab.

[Stormin Mormon]

Be nice to know more about the operation. What kind of new work, and used for what? Give us some idea how large, how much wood, how much load, etc.

[Gordon Shumway]

I second the advice of going to McFeeley's. Also check out McFeeley's recommendation of size of fastener to use for a given application. Like dadiOH said -- #8 minimum for any type of structure. For furniture #8's are OK.

In my experience HD/Lowes and other big box stores don't have the quality McFeeley's has. I did break ONE of their screws once. I was screwing into some maple and hit the body of a previous screw at about right angles and the latest screw snapped. That's the only one I ever broke out of the thousands I've used.

[nestork]

I can't tell for sure from your picture, but I think what you're calling a "Star" drive is a Torx drive.

Everyone acknowledges that Torx is just as good a drive as Robertson.

But, P. L. Robertson, a Canadian, had his drive patented and both the screws and screw drivers in production back in 1909. In it's day, the Robertson drive was hands down the best drive available, and has been for many decades afterwards.

P. L. Robertson wanted Henry Ford to use his screws in the Type A automobile, and Henry figured out that he could save about 7 minutes in the production of each Type A car by switching to the Robertson drive. That's because the Robertson screw could be placed on the screw driver and then driven with one hand. With the slot and Phillips screws, you had to hold the screw with one hand (so it didn't fall off the screw driver) and turn the screw driver with the other hand. Ford really liked the Robertson design and realized those screws could make him more money.

The problem was that Henry didn't want to buy Robertson's screws; he wanted a license from Robertson to produce them in his own factories. Robertson was concerned that he wouldn't know for sure how many such screws Ford was producing and therefore couldn't be sure he was getting paid for all the screws Ford made.

The two men never struck a deal, and the result is that Robertson screws are common throughout all of Canada, but a comparative rarity in the US.

But, Torx screws are becoming progressively more common throughout both the US and Canada. Torx screws allow the operator to apply just as much torque to the screw head as you can with a Roberston drive, which far more than you can with either a Phillips or slot drive. And, Torx has the same advantage as Robertson in that you can put the screw on the driver and it'll stay in place as it's being driven in.

It's too bad Robertson and Ford couldn't strike a deal. Then all Americans would have found out how much better Robertson drive really is. Now, every American is buying Torx screws whenever the opportunity presents itself and no one can blame them. After all, Torx drive is just as good as Robertson.

[krw]

Don't do that. Sheetrock screws are for, um, sheetrock.

Yes.

Yeah, I sometimes use sheetrock screws for other things, too, but never in anything that is load bearing or that matters. They're probably fine for partitions but it's better to get hardware intended for the use.

Don't do it. Get the appropriate hardware.

[krw]

McFeeleys is good but they don't carry everything and they're sometimes on the expensive side, particularly for things that aren't vanilla screws.

[DerbyDad03]

No, what I'm calling a "Star" drive is a "Star" drive.

(Actual link from

is too long for my newsreader to accept)

I wonder what they say about Star.

...snip...

[Gordon Shumway]

What you and Lowes call a "star" drive is in fact a "Torx" drive. Torx is the trademark name for a type of screw head characterized by a

6-point star-shaped pattern. There are 5-point tamperproof patterns as well.

[DerbyDad03]

Here's something interesting...

McFeely's sells Torx bits and Torx drivers in all sorts of configurations, but they don't sell any Torx drive screws. They only sell Star drive screws.

In fact, if you search for Torx, their search engine asks you if you meant star. Go figure.

Of course, then there 6 lobe at Fastenal and the always popular "hexalobular internal".

[Frank Thompson]

square vs Torx... which is preferable?

[Vic Smith]

I prefer square. Never had one slip at all. Very little pressure needed.

[bud--]

A couple carpenters on a job said square was far better than phillips, and torx was better than square.

[RobertMacy]

I wonder if my 3Rill has a Robretson's Head driver?

Another reply suggests not a good idea to even use deck screws, only 'construction' screws.