What to do about curved/ warped 2x4's/ lumber?

[beppington]

Anybody else think 2x4's & other lumber from Home Depot/ Lowe's seems a lot more curved/ warped than a decade or 2 ago?

Maybe it's just me, but when I buy boards & put them in my (enclosed but not air-tight) barn, seems that in less than a week they're incredibly warped, basically useless to me.

Can this be prevented?

Can they be straightened once they've warped?

 

[Richard]

I've had that happen more with treated lumber than normal lumber. I try to lay all of mine down in my basement so it's stacked on each other (weight from above holding everything flat). I've even gone so far as setting something on top of it.

When I get treated lumber, I simply try to use it immediately so it won't have time to lay around and twist.

 

[Craig Clayton]

Sir
When ever I buy SPF( spruce pine fir ) for a building project that I want to have dry and straight ,I bind them with chains. The only problem is the lag time to purchase them 6 months earlier than they are actually required. I lay them with small 1/2 by 1 strips between layers and bind them with chains 40 to the pile. Spruce left to its own and not nailed in a framing wall makes proplers , or water skiis. Kiln dried means the truck drove by the kiln and shifted gears.
Craig Clayton

 

[beppington]

I've tried laying heavy stuff on them, & that has helped some sometimes, but it seems to eventually overpower the weight & warp anyway.

I've noticed that a strapped bundle of lumber at HD sometimes springs apart when they cut the straps, & right away some of the boards are warped.

I suspect, but haven't confirmed yet, that dampening lumber may help.

This also happened 2 nites ago. Had a 2x4x8' PT laying on my concrete garage floor. Within 4 days it was very warped. I moved it from the concrete onto a piece of plywood I had laying on the floor right next to it, & the next day the 2x4 was much, much straighter. Coincidence? Not sure yet.

I just realized: I think they changed the pressure treating chemical at some point, from some cancer causing chemical to some copper-based chemical. Maybe that has something to do with the seemingly worse warping these days?

 

[Mousefield]

A couple of years ago had to buy some lumber for a company I worked for. Even after picking through a stack of lumber the best ones were still crap to say the least. Lucky I have some nice Douglas firs on my place that I have been able to mill. A couple had died and took down 4 altogether, 70-90 years old and up to 4 ft diameter. After getting milled by a band saw on my property they get stickered between layers and then air dried for at least 6 months. You can't buy what I have at the store. Depending on your project and area you may try to talk to some band saw mill operators who would cut to your specs.

 

[tallyho8]

I have frequently stored some 2x4s left over from a job. In a few weeks one may be badly warped and all the others still like new. I believe that certain cuts of wood tend to warp more than others.

 

[dave1949]

I think the lumber in general is not what it used to be. I know people have been saying that for 30 years now, but it seems to continue to get worse. Like Mousefield said, you can't buy from the store what he has.

For PT, I think the key is to keep it out of the sun while it dries out, or use it quickly before the sun gets on it. It's always soaking wet from outdoor piles at the lumber yards.

LOL on kiln dried means the truck drove past the kiln. There is always going to be a squirrely board or two in a stack that corkscrews or whatever, but if you are getting half-way decent lumber to begin with, there shouldn't be that many if you stack them with some stickers and put a tarp over it.

It may be that the computer controlled and optimized saw at the mill will take cuts that an experienced sawyer would never do, knowing it isn't going to be a good board.

An old builder told me that back when, they never considered putting on drywall or plaster until a house had been closed in and sat over the winter giving everything a chance to dry out. Plus if a board did really warp, you could replace it.
Dave.

 

[Baby Grand]

I used to drive a lumber truck for a local building materials supply company in the 70's. I delivered a lot of framing lumber. I also unloaded the "units" of lumber from the railroad flatbed and boxcars as well as tractor trailer loads from the docks. My duties included making up the orders that went out on my truck and other guys' trucks. The lumber units were secured with two 1.25" wide steel straps that had to be cut before various sections and lengths could be assembled into an order and restrapped for loading on the trucks. The lumber that sat up top, uncovered, and out in the sun on railroad flatbed cars for who knows how long (I think it mostly came from the Pacific Northwest) was the worst. I remember cutting the straps was always a cheap thrill as the whole unit would burst apart due to the warpage of the outer few layers. Boards, steel strapping and angry carpenter bees the size of unshelled peanuts went flying all over the place.

So to bring it all home, this isn't really a new phenomonon to me, but more a symptom of how the lumber was treated before you get it.

-Jim

 

[jbarker855]

It will help if you can lay out your lumber in a manner such that air has access to all sides of it. Laying a board on a concrete floor is not a good idea. Moisture will evaporate much slower from the side of the board that is facing concrete, causing it to warp. "Stickering" boards (placing narrow slats of wood at bottom of pile and between each layer) will help to decrease warping. That being said, you need to have decent lumber to start with and even then, some boards will warp. I bought about $1000 worth of lumber from Lowes about 2 months ago, and was very surprised at the quality and straightness of their boards. Maybe it has something to do with geographic location. I am in western NY.
-Jay

 

[charlz]

Lumber seems to have a much wider grain these days, not as dense, and I think that contributes to the warping.