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is there any major *funtional* difference between framing with screws of nails. I was at a friends house the other day and one of the construction magazines he had had a thread where by code, framing had to be done with nails as screws were harded, thus more brittle.
just want to get some views on this
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Screws resist pullout better but, in general, don't have the shear strength of a nail.
It's tough for me to find decent cut wood screws locally these days. I mostly mail-order them.
It's scary to see what people do with rolled drywall screws.
*I guess it depends on what you do. Most of my work is renovations in brick houses. BTW, anyone know of any other good screw dealers other than mcfeelys
*A drywall screw is roughly equivalent to a drywall nail (yeah, I know, slightly different spacing is required). Now look at a drywall nail versus a 16d framing nail and think about cross-sectional area.
*I suspect that if the nailing/screwing schedules were properly set up, the only differences would be material and labor costs.
*This was covered in infinite detail a while back You might want to search the archives.
*Has anyone considered using sheet metal screws? These have better metal than drywall screws but share the pullout [and ease of removal] advantages of drywall screws. I wouldn't use the self-drilling type in wood tho. -Peter
*There are other screws on the market besides drywall screws! Nobody with half a brain would do framing with drywall screws.I will assume John meant screws of size and cross section similar to framing nails. I've got lots of 'em and they're every bit as tough as 16d common nails.To answer your question regarding functionality...It takes longer to install a screw, so I don't use them very often. But there are a few special situations where screws are better:1. If the impact of a hammer or nailer is going to cause damage to something on the other side of the wall.2. If there isn't room for a hammer, sometimes I put a long extension on my drill and use it to zip in a screw or two.3. If something isn't as straight as I would like, sometimes I can pull it together with screws.By the way...Rolled threads are generally stronger than cut threads of equal size. This is sometimes important in the engineering of cars, trucks, and airplanes, but it doesn't make much difference in wood.By the by...Not all screws are hardened or brittle. Many are just a medium grade of steel. Then there's stainless. And brass. And bronze. And aluminum. And copper....
*I can't see any advantage in new construction of screws over nails.In remodeling screws can get in where nails can't. Drywall screws are a no no in my opinion but others may not agree. With the new magazine screwguns it may be practical but it seems like it would still be slower than nailing, especially versus gunning the nails. Someone may be reinventing the wheel. IMHO Skip
*my neighbor asked if he could borrow some screws last summer. He said he needed "big ones". I said "big or long"? he said "long". i learned a long time ago, don't ask what for or you end up doing it for them. I showed him some 2 and 3 inch drywall screws. He said "they'll do". couple days later big damn antique oak somethin or other came crashing down on top of his wife while she was watching t.v.. She's ok now....still makes me laugh though.
*Hey Rich, just hope the lawyers don't see this thread, or you might find yourself testifying in front of a jury at an attempted Murder Trial...lol
*This outfit has some structural screws. For repair and remodeling, it's good to be able to do fastening without all the slamming and banging with thousands of art work in the next room.Another good application is strapping/furring on roofs for cold roofs. Screws provide more uplift resistence against wind for metal roofing.http://www.grk-canada.com/front.htm
*attempted murder? maybe that was his plan!
*Piffan, Not only do they provide more uplift protection for metal roofs, they also provide a lot more protection against any kind of extraction. A typical toenailed rafter will pull out with only 208 pounds of pressure. whereas one that is lag screwed in with 3/8ths by 8" lagscrews will take 2,783 pounds to remove. The failure point will get higher as you get to hardwoods like Oak/Ash etc. The simple reason you don't see it done very often is labor. It costs like 10 cents in labor to drive in toenails while you may have as much as $15.00 to properly lagscrew in 3/8ths by 8" lags. In my opinion that is penny wise and pound foolish. High winds do occur, tornados, hurricanes, earhquakes, and straightline winds all can exceed the failure point of a toenailed roof. When that happens the roof blows off and the walls come tumbling down. The house at that point is a total loss along with your possesions and occasionally a life. The reason it happens is Americans do not understand value. they think value is simply bigger or fancier. The idea that a well made house should be able to withstand weather is beyond their thinking. Partially that is the builders fault. We haven't done a very good job of selling that sort of value because we don't like to do things that slow us down. It's far more satisifying to nail gun a wall together than to do the work needed to make the building holdup for centuries. I can accept the idea of cost restraints if we were building houses for less than a hundred thousand, by why on homes costing well over 5 million do we still toenail?
*>A typical toenailed rafter will pull out with only 208 pounds of pressure. whereas one that is lag screwed in with 3/8ths by 8" lagscrews will take 2,783 pounds to remove.Are you measuring the breaking strength of the fastener, the force the wood will withstand before the fastener pulls out? This 13:1 improvement doesn't sound right.
*>This 13:1 improvement doesn't sound rightIt sounds reasonable to me. Take a scrap of 2x4 a couple feet long, and a common nail and a deck screw of equal length. Put them in so their heads are 1/2" above the surface. Then pull them both out (if you can) using a claw hammer. The straight sides of the nail slide out, the resistance is just the friction of the wood against the nail. The screw, if you can get it out, has to rip wood out of the hole in order to move at all. Toenailing keeps fireblocks from falling on the floor before you get the sheetrock up, but not a whole big bunch more than that. ;-)-- J.S.
*x John Sprung, Tauton press Framing toofs page 129 I also read something in the UBC but can't remember the page or evan the chapter. If it's really important I'll look it up next time I go by the library.
*I wonder what the 3/8" lag screws are going to do to the truss? I would be concerned that the plate would be compromised.
*We can use just one toe nail if we want.But we still have to strap each and every truss or rafter. Takes about 14 more nails for each strap.
*Ralph, Simpson straps are a good choice if you are stick building (which admittedly most homes are) I see them in Calif. However I never see them around here. Wish I did, but not in Minnesota.
*Ron, On page 126 they show what an overloaded lagscrew did to the truss, (it pulled through the truss, but that was after 2,783 pounds {compared to 208 pounds that a typical toenailed rafter failed at})
*Hard to inmagine anyone framing with 3/8 lags. 3" deckscrews are another story though. If I'm only doing small remodling stuff with a few things going up here and there I often use deck screws. I can't break em off if i try. It's easier to reposition stuff, and does less damage to the surrounding stuff. Drywall screws, on the other hand are no good for anything but drywall.Steve
*I was thinking more what it might do to the plated connection at the heel of the truss. The metal plates are often right over the wall. Did that picture show the bolts going through the plates?Keep in mind that fastening the trusses to the top plates is only one step in the process of making a structure wind resistant. Nailing the roof plywood down well and creating a continuous load path from the truss down to the foundation are all important.
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is there any major *funtional* difference between framing with screws of nails. I was at a friends house the other day and one of the construction magazines he had had a thread where by code, framing had to be done with nails as screws were harded, thus more brittle.
just want to get some views on this