Specifically wall studs.

Would quarter sawn Douglas fir wall studs be any stronger at all than plain old Doug fir studs?

What structural effect happens between the two types of sawing

While quarter sawn studs “may” be stronger I could not find any code variance to that effect. It all comes under SPF (Spruce, Pine, Fir) as far as I can see.

When we needed stronger wall studs we used SYP (Southern Yellow Pine) which is about 15-20% stronger.

I learned something new today.

From Plain sawn, Quarter sawn, and rift sawn explained

Because of its tight grain pattern, quarter sawn wood is stronger than plain sawn wood. It also tends to twist and cup less because of its smaller surface area and is less likely to split during construction.

Regarding "the code," the tables in the building code are done with a safety factor built in. How the wood is sawn isn't going to move the needle structurally, unless you're trying to do something that doesn't fit the tables, in which case you'd need an engineer.

The species of wood does matter, and the grade. Wall studs are part of a system, and considering they'll let you go 24" on center, very strong in the direction they are meant to be loaded.

Here is a good website where the code is available free: https://up.codes/code/internat...ential-code-irc-2015

The ICC's own website is meh, because they want you to buy it.

I see you live in IL, so your local city or town has adopted some version, there is no statewide standard. Here is a code directory by locale

As long as your lumber is marked with credible sourcing, it can be expected to perform as graded, and you don't need an engineer, only some reference tables.

Put a different way, if there was a stronger part of the tree that you could get from how it was cut such that part of the same tree was significantly weaker, we'd have weird looking trees and a lot of waste.

Quarter sawn etc. is to be considered when you're making furniture or doing flooring.

Based on what I see in the big box stores, the days of straight, tight-grained Doug fir are gone. Hemlock or other "white wood" seems to be what's on offer now for studs.

Yeah, you need to either build rocking horses, boats, or hockey sticks now...

Seriously though, forests have now been bred to be "fast growing," and they are managed for maximum yield. If you want "old growth," you'll need to do some illegal logging.

If you wanted more strength, you could face the studs with plywood, before the drywall goes on. This also makes it much easier to hang pictures, etc.

quote:

Originally posted by c1steve:
If you wanted more strength, you could face the studs with plywood, before the drywall goes on. This also makes it much easier to hang pictures, etc.

I knew a guy that faced all of his walls with plywood . I had never seen that before . That , plus all of the hurricane clips and ties made for an extremely strong house . It added a lot to the cost but he lives here in Louisiana where hurricanes are a concern .

The distinction is the way the grain runs when the boards are cut from a log. Cutting quartersawn planks is more work and there is more waste (you get fewer boards out of the same log) than with plainsawn/flatsawn, so quartersawn boards are significantly more expensive.

Random image from the web:



Quartersawn wood is much less likely to cup or warp and are just generally more dimensionally stable with the moisture changes that happen with humidity changes.

If you're gluing a bunch of boards together side-by-side, that really matters - a butcher block made with flatsawn grain orientation can tear itself apart from the stresses of boards cyclically warping in different directions with moisture changes, or can badly warp across the entire assembly if a number of boards cup or warp the same direction.

If you really want something not to warp or twist - like a guitar neck, for example - quartersawn is definitely the way to go.

In most woods, there are not meaningful strength or stiffness differences between quartersawn and flatsawn boards, and what differences exist have to do with loads that try to bend the board, not loads along the length of the board like you have with wall studs (a warped board will be less strong in the sense that it will buckle more easily, but that is not relevant in house framing).

There could be a small difference in strength for floor joists and rafters and stuff, but house framing is HUGELY stronger than the actual loads involved (excepting stuff like tornados and earthquakes) and the strength limitations have more to do with how the boards are attached to each other than the strength of the boards themselves.

So fundamentally, no, for house framing, there is no meaningful strength benefit.

Quartersawn would by more pleasant to actually do the framing with, because you wouldn't have to deal with a bunch of warped boards, but the end product would not be meaningfully stronger.

Home depot sells Warped Sawn....

Thanks to those folks choosing to shed some light on this for me.

This!!

quote:

Originally posted by HRK:
Home depot sells Warped Sawn....