Framing wall...how straight do 2x4's need to be?

29925 Views 26 Replies 12 Participants Last post by kwikfishron, Dec 15, 2012

Freakaloin

Discussion Starter · Dec 13, 2012

Most of the 2x4's I have for an exterior wall I'm constructing are slightly bowed. Also, the boards i'm using for the top and bottom plates are slightly twisted. Can they be a little off or do they need to be close to perfect? Will the boards straighten out when nailed together or should I get new lumber? Thanks

1 - 20 of 27 Posts

Trucon01

· #2 · Dec 13, 2012

To start...

When buying lumber, you should always look down the length to make sure it isn't warped / twisted too bad.

When you get the lumber at home, ALWAYS crown every piece and mark them accordingly. Make sure your 'C' is always facing the inside of the room.

Your top and bottom plates should always be your straightest pieces. FYI -- Bottom plate should be PT 2x4 or regular 2x4 with sill foam underneath.

Thats what I followed when I started framing my basement...

Freakaloin

Discussion Starter · #3 · Dec 13, 2012

So any twist in bottom and top plates is unacceptable?

joecaption

· #4 · Dec 13, 2012

The top and bottom plates are the most important, if there off the wall will follow the curve.

Trucon01

· #5 · Dec 13, 2012

From the sounds of it, you got your lumber from the cull pile?? :no:

Freakaloin

Discussion Starter · #6 · Dec 13, 2012

So I'll definitely replace those boards. Can I get away with slightly bowed studs? I used the straightest 2x4's around door so it's just the studs which will make up the basic wall.

Freakaloin

Discussion Starter · #7 · Dec 13, 2012

Trucon01 said:
From the sounds of it, you got your lumber from the cull pile?? :no:

Lol no I made the mistake of letting my wife pick em up at Home Depot. Ooops!

hammerlane

· #8 · Dec 13, 2012 (Edited)

Freakaloin said:
Most of the 2x4's I have for an exterior wall I'm constructing are slightly bowed. Also, the boards i'm using for the top and bottom plates are slightly twisted. Can they be a little off or do they need to be close to perfect? Will the boards straighten out when nailed together or should I get new lumber? Thanks

Theory on crowns facing out:
The crown should face the inactive side of the wall. If you are building an exterior wall, the crowns should face toward the outside...which would be the inactive side...since inside you may be hanging cabinets(inside in this case is the active side of the wall).
http://www.youtube.com/watch?v=6lSJ4Mwr-Uw

Theory on crowns facing in from the Journal of Light Construction:
I've framed several houses with 2-story balloon-framed exterior walls. On one such house, three 16' tall walls formed the living room. I selected studs with very little crown, and crowned them out, but when I was later installing the ceiling joists over these walls, I noticed the studs had all developed much greater crowns than they had when the wall was built. I wondered why.

On another occasion, a fellow framer stopped by my job, and while he was talking to me, he flipped over the 2x12's on the top of the pile, noticing they were starting to cup. This would let the other side dry out, of course.

The proverbial light bulb turned on! The 2x's were exposed to the air/sun on three sides, so those faces dried out and pulled together. The bottom face remained moist, due to its contact with the board under it. I reasoned that the same thing was happening with the studs. The edge of the stud attached to the sheathing was not drying as much as the rest of the stud. As the exposed parts of the stud dried out, those wood fibers pulled together, resulting in a "cup" along its length, thereby increasing its crown! Atleast that was my theory.

I tested my idea on the next house which had a 19' tall balloon wall at the entry. Crowns in, not out. When I got on top to set the joists, that wall's studs were practically perfect!

I now frame all my exterior walls this way, still checking the studs' crowns after the wall has been up for awhile, and most all of them straighten out, or atleast end up with less crowns. The balloon walls still end up nice and straight!

Tom

See less See more

Trucon01

· #9 · Dec 13, 2012

Man card may be getting pulled... The wife picks up the wood?? Thats half the fun!!!

Freakaloin

Discussion Starter · #10 · Dec 13, 2012

This is a car port conversion. It's was already partially converted when we moved in. The front has two sliding glass doors. For some reason the inside of the carport has hardiboard so I'm gonna put hardi on exterior and interior walls. If that changes anything...

Freakaloin

Discussion Starter · #11 · Dec 13, 2012

Trucon01 said:
Man card may be getting pulled... The wife picks up the wood?? Thats half the fun!!!

Lol I lose...

Freakaloin

Discussion Starter · #12 · Dec 13, 2012

2

heres what i'm talking about. i don't think it's that bad? these are bottom and top plates. i really don't want to drive 30 minutes to the store if not needed...

See less See more

kwikfishron

· #13 · Dec 13, 2012

There’s nothing wrong with those boards. You should have no problem straighten them out as you fasten them.

Reactions: 2

Freakaloin

Discussion Starter · #14 · Dec 13, 2012

awesome! that's what i wanted to hear...thx"

carpdad

· #15 · Dec 13, 2012

Top and bottom plates should be straight and even as possible. Wall framed with warped lumber can not be checked for square with accuracy. This is when wall is framed on deck.

Bottom plate must be nailed to the string line, so some warp and crown can be corrected.

Top plate must be checked against stringline and braced before anything goes on top.

It makes work easier to use the best pieces. Your lumber looks fine, but I would make sure the wall is square before sheathing it.

woodworkbykirk

· #16 · Dec 13, 2012

as already mentioned your plates should be deadly straight although this isnt always an option.. in that case make relief cuts in them to take the tension out of the crown so they can be nailed to the floor or ceiling straight

studs.. no more than a 3/16 crown is fine .. use totally straight studs for making corners, posts and king + jack stud combos for roiugh openings.. . studs that arent perfectly straight are used in the field of a wall (filler studs) or stacked aside to be cut up for cripple studs and sils for r.o's

the theory behind crowning out is so that when cabinets are hung the box wont rock on the wall it just needs to be shimmed into plumb hanging off the wall

Reactions: 1

spring3100

· #17 · Dec 13, 2012

As a rule,I always buy Grade 1 lumber from a reputable yard,not the big box stores,cost a little more,saves boku time and headaches.
If you are a DIYer,screwing with crowns and bows shouldn't be something you concern yourself with,your work will also look much better.

woodworkbykirk

· #18 · Dec 14, 2012

lol.. paying more to get lumber than at a bigbox...
i get higher grade lumber at the lumber yard and at 20% less than the bigbox stores

Fix'n it

· #19 · Dec 14, 2012

around here, the box stores have put most of the lumber lards out of business.

i hate picking out lumber ! checking 100 boards to get 25 good ones, you can have that.

woodworkbykirk

· #20 · Dec 14, 2012

the main lumber yard was bought out by one big box yet have kept their operations the same. its why rona bought them. the regular big box stores cant get the contractor sales.. kent's has terrible lumber and the prices are pretty much the same.. hd cant handle the volume plus they only have 2 delivery trucks shared between 2 locations

pierceys/ rona has 6 locations and roughly 50 trucks

1 - 20 of 27 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.