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Building with rough sawn lumber 3

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WARose

Structural
Mar 17, 2011
5,594
I designed a wood structure few months back. (Not particularly big.) Now in the process of building it....it turns out the wood to build it comes from a guy who runs his own portable mill. Inspecting the wood, this stuff is top quality. I called out #2 on the drawings....and this stuff is several steps above that.

One problem though: it went straight from the mill to the site. (I.e. it hasn't gone through anything like a planer mill or the like.) As a result, it's off (here and there) by 1/32 or 1/16th. Also I am puzzled as to what to tell the contractor.....I have heard stories from the old-timers about building with "rough sawn" lumber.....but I don't know enough about it to know what to say.

What do I say? Some thing like: we'll ride each horse as we come to it? Trim it up on-site? It sound like me putting out each fire to be frank.

Any advice welcome.
 
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My biggest concern would be with moisture content. If it's still "green" you could end up with lots of creep issues.
 
No, it's in good shape as far as MC goes.
 
Do you have a lot of connectors and joist hangers?

If a member is 1/16th of an inch large (*edit...larger than it is supposed to be)*, it probably could be snugly fit in a normal sized connector, but anything more than that probably wouldn't fit.
 
What's wrong with bringing a portable planer on site to "dress up" lumber for critical areas?
 
Do you have a lot of connectors and joist hangers?

Nope.

If a member is 1/16th of an inch large, it probably could be snugly fit in a normal sized connector, but anything more than that probably wouldn't fit.

I'm not sure I follow that statement....but I would like to be clear that virtually no member/board is of that size.....what I am saying is they are off by that dimension (or 1/32 in other cases). E.g. instead of a 2x4 being 1.5" x 3.5" in actual dimension....it is (for example) something like 1.56" x 3.53".

What's wrong with bringing a portable planer on site to "dress up" lumber for critical areas?

In a word: money.

I am essentially being asked for a way around that.
 
Why is this your problem? If it was their idea, let them build with the odd size lumber.
 
Why is this your problem? If it was their idea, let them build with the odd size lumber.

The project was for a regular client of mine.....and he has asked me to help resolve the situation.
 
If the framer is good, you could instruct them to shim and block as required. It seems like dimensional (as opposed to length) tolerances are off. So your joist cavities will be a bit bigger, studs won't be flush, elevations will have to be checked. Major problem I see is applying finishes (drywall, flooring, etc) because nothing will be true and plumb (it never is...though).

I agree with above, that creep and shrinkage will be a concern down the road.
What you'll save in not planing, you'll spend on making the finishes work.
 
This should be in heavy dark print, from post above in any contract..

What you'll save in not planing, you'll spend on making the finishes work.

and I'll add Also the cost of trim, hardware and setting electric connection boxes.
 
Is there a concrete slab nearby that can be used as a "true" surface? If so, have them panelize the walls on the slab, using the face that's "flush" for the interior face of exterior walls that aren't shear walls. That'll help with drywall finishing. Exterior sheathing and siding won't need to be as true of a surface to accomplish an acceptable appearance. Dress boards at shear walls to ensure adequate panel fastening AND interior finish quality. For interior partitions, use heavier drywall and put your studs at 12" on center, staggered on opposite faces of a 2x6 plate (actual spacing on either side will be 24"). That'll let you get a true face on each side of the wall, and have the added benefit of running wires without drilling and some extra sound isolation.

Carefully select boards that are the closest for thickness for your plates. That'll minimize height variations around your walls.

Sounds like it isn't a structural problem, and any "solution" you come up with is going to add cost somewhere.
 
I hope your building inspector is friendly. As I understand it the building code requires graded and stamped wood, and self-sawn lumber does not comply.
 
WARose:
Maybe you want to do some on-site grading and sorting. And, you want a framer who is smart enough to watch out for some of these things. Knots near or on edges are not good in spanning members, unless they are on the compression edge of the member and the camber is up. Splits, checks, grain angle may be not be a good a thing at times either, and someone has to watch this. You don’t care so much about exact thickness, except on sill plates and the like. Stand members on edge on a flat surface or a couple beams, or saw horses which are in a plane, camber up, and sort the members by progressive width (and/or thickness) change. A 1/32” or maybe even a 1/16” width difference shouldn’t make that much difference as long as the change is gradual. Then, pick the 10 studs you need for a given wall from the same group of widths in the sorted stock. In part, be careful not to put a 3&6/16” stud btwn. two 3&9/16” studs, although that narrow stud would not normally be a problem along-side another stud where a double stud was needed. Put the bellies on the studs in the same direction. Assemble wall sections on the platform, with what needs to be the best side (truest side) down on the platform. You want some carpenters who think on their feet, and know what they are doing, not just grabbing the next piece of lumber without some thought. Maybe, you want a good table saw on site, 10” or better yet 12”, so you can rip some of the lumber to a truer size. This sorting doesn’t require the best carpenter on the job, just some instruction and attention to the important details, by a few junior laborers, a string, a straight edge, ability to sight down a board, etc.

Then, explain to your client that sometimes when you save a buck or two without thinking of the other consequences involved, you spend that savings later to make up for problems caused by your ignorance. Alternatively, they used to hew logs with a broad ax and they made perfectly good beams and timbers, for a slightly different kind of framing. They built lots of barns and timber frames with rough sawn timber, and they worked just fine. They weren’t trying to fit pre-made cabinets, vanities, stairs, fixtures to a perfectly flat plane. They scribed things to fit, they shimmed things to fit, they did have levels and plumb lines. They weren’t using .5” sht. rk., they were plastering to fit, they used doob and wattle btwn. timbers, and the like.
 
Thanks to everyone for the feedback I have gotten.
 
Rough sawn lumber was less of an issue when houses had plaster walls and ceilings. The alignment of wall studs and roof members mattered little because the plaster was troweled on and then smoothed out by a craftsman with a good eye. Now we applied smooth/finished materials to the wall/roof and the unevenness can be an issue. I have worked with both, and highly prefer dressed lumber. Even with dressed lumber, alignment is challenging. I do think any money savings will be offset by more alignment labor and an uneven final issue when using the "old values" of rough cut.

The dimensional differences you are citing though occurs in the depth of even dressed lumber. So most likely no difference there. Thickness however can be an issue due to connectors cited already. Most rough lumber I have seen varies by 1/4" to 1/2" in depth and up to 1/4" to 1/2" in thickness. The numbers you site are not a problem with depth. I went through an entire bundle of dressed 2x10s years ago looking for 15 of them with consistent depth and camber. I had a floor area that was going to be highly visible to someone at eye level coming up a stair. The floor was going to be highly varnished with a big window on the other end. It took the entire bundle to find 15. The depths ranged from 9.0625" to 9.4375". I got 15 within a sixteenth of each other with similar camber.

Examples of the old rough cut values when using sheets of smooth materials rather than plaster:
[ul]
[li]A rafter with no finishes on the bottom, match the tops to the ridge board and you are done. A rafter with roof deck on top and drywall on the bottom, match the bottom and hope the top of roof looks ok. Make sure your rafter pattern has the HAP consistent so the excess is under the rafter unless finishes are on top and bottom in which case your HAP varies.[/li]
[li]Align walls studs on the interior and hope the exterior unevenness is absorbed by decking, siding or brick[/li]
[li]I inspected a house that was well over 150 years old with beautiful wood floors. The top was planed but the underside was unbelievable. They hand planed each board where it sat over a wood joist with a hand plane. The only planed it about a 1/4" wider than the joists. The got the depth correct but we are talking thousands of individual hand planing locations.[/li]
[li][/li]
[/ul]
 
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