Weathered wood framing

[txstruc]

The subject of weathered wood framing has come up in my career several times. It usually comes up when a contractor is delayed an extended amount of time such that unprotected wood framing gets weathered to an extent that it is discolored and actually deteriorated in severe cases. It comes up either during structural observations by EOR or another agency as a perceived deficiency and the agency is looking for the EOR to determine whether everything is ok, or not. As EOR, I am not comfortable taking on that liability. Does anyone know of another expert that takes on this role and can report on the structural adequacy of the materials in a credible fashion?

 

[XR250]

I was just thinking about this. There is a 5 over 2 construction site down the street where an entire 18 wheeler load of floor trusses was dumped there (in the dirt). It has rained everyday since then. I imagine the plates are starting to walk. It continues to alternate rain and sun here and it does not look like they are even close to installing them. Not even covered up with a tarp. Was hoping I did not get a call to evaluate them (def. a job i would turn down)

 

[lexpatrie]

Just take the job and reject them.. simple enough.

There are ways to assess the wood in both destructive (lab testing) and non-destructive ("radar", tiny drill probes) but what about the plates?

What about sending three or four off for full scale testing if the batch is reasonably large? TPI requires occasional testing as I recall, that protocol might be viable. Then again, question what size would constitute statistically significant, but concrete cores it's 3, isn't it? 3 doesn't sound statistically significant either.

Connection plates would be more of a concern for me.

 

[bones206]

This is a good reference:

https://kktruss.com/wp-content/uploads/2012/04/ttbmold.pdf

I'm more worried about the mold issue for health reasons than structural reasons. Building owners shouldn't have to do mold remediation the day the GC hands them the keys to their new building (unfortunately speaking from personal experience).

 

[lexpatrie]

If it's sitting in situ it could have biocide on it from the go, or mandated by the AHJ.
Most attics hit in the 120-130° F range which is pretty hostile for mold, it won't kill it outright, but the growth rate is pretty minimal.... until it gets really humid or wet.

 

[txstruc]

@lexpatrie, unfortunately its not that simple. They will require from me a report of what action is needed to correct any deficiencies. If I take it on only to say "tear it all down" then I'm essentially not taking in on...just taking their $$$.

 

[txstruc]

One particular project I'm dealing with this on is on the Texas coast and another one is on the Florida coast. So, quite wet. In both cases, the AHJ has halted construction due to their concern for the quality of the weathered lumber and are "requiring the EOR to review and approve" before they will release their construction hold. I have looked and looked for any resources on this, even just "best practices" but really can't find anything that would serve as a guide for evaluating structural wood materials effected by weathering during construction. I am leaning toward directing them to get an "expert" or "experts" in this to produce a report and submit it to me for review and then I would be happy to provide my recommendations based on the "experts" findings. Problem is, I can't even find that such "experts" exist. This has continued to feel like uncharted territory.

 

[bones206]

Try contacting SBCA. They are the ones who put together that fact sheet I linked to.

 

[gte447f]

txstruc, based on my experience, this is not something that typically falls within the basic scope of services of the SEOR, so I would not accept this as a requirement on me, regardless of what the AHJ says. Furthermore, if it is not something that you are comfortable with within your area of competence, then you shouldn't do it. I like your inclination to require an outside expert's evaluation and recommendations for any necessary remediations. Like you, though, I don't have experience engaging or working with such experts. If you could work through the issues with an outside expert, it would be a great way to learn and broaden your knowledge and experience, and maybe your areas of competence and services in the future.

 

[lexpatrie]

So the materials were improperly stored, got wet, and now you're supposed to certify they are "just fine."?

That sounds like a particularly bad idea, and how are you suddenly involved? Are you the original EOR?

This sounds like a "them" problem. You can either a) tell them rip out and replace, no charge for your time, or b) wade into an area you don't feel that confident in.

The only thing I can think of is back when, Wisconsin used to have rules for "reused" lumber, but it had to be calculated for (I think, C[sub]D[/sub] = 0.9 across the board). Discoloration (fading) wouldn't be all that concerning, but elevated moisture content and exposed to weather all manner of things get into the wood. I'd still be more concerned with the truss plates (I'm presuming these are prefabricated items), can't the supplier engage?

I mean, what is your plan if they store the rebar underwater for six months? I'd reject it. your wood is somewhere between "nah, it's fine" and "it's totally busted" but how do you arrive at that conclusion in accordance with an accepted methodology? There is also the enabling the contractor to think this can be normalized, which means they'll do it again and call you again.

 

[gte447f]

txstruc, what happened on these two projects that was so out of the ordinary that these projects were exposed to excessive weathering beyond incidental exposure to weather that could normally happen during construction on any project? Seems like if the contractor didn't store materials properly or otherwise left work in progress unprotected for extended periods of time, then the onus should be on the responsible party to demonstrate that everything is "OK".

 

[FootNMouth]

If framing within the metal plate connected wood trusses are the concern, then I recommend having the specialty structural engineer who sealed the truss design drawings assess them.

WoodWorks may be of some assistance in finding an expert but I would not be too hopeful.

 

[txstruc]

@lexpatrie, yes I'm the original (current) SEOR. The materials are the as-built condition, but yes there are also materials stored on site that are also weathered.
@gte447f, on one of the projects it is rumored that they lost funding and therefore it sat for several months, more than twelve in fact, in various stages of completion (multifamily garden). On the other, the claim is that a site utility issue kept them from continuing framing. Regardless, in my opinion, the GC is responsible for keeping all materials protected during delays.

 

[XR250]

If framing within the metal plate connected wood trusses are the concern, then I recommend having the specialty structural engineer who sealed the truss design drawings assess them.

I doubt that will ever happen. I can't even get one of this guys to give a contractor a truss repair detail for
damage that occurred during transport/dropoff.

 

[lexpatrie]

Well, I guess somebody (truss fabricator) doesn't want their retainage released.....

I'd probably contact the building official and see if they'd send a letter requiring a repair drawing for the damaged truss (to the truss supplier).

I take it this is a fairly large project? Are the affected trusses just the roof? How many trusses would be involved, or square footage, roughly?

 

[jerseyshore]

Is it trusses or just studs/ 2x's/ LVL's etc? Or both?

I agree with gte and lex, this seems like outside what an SEOR should be expected to know. I think you are right to try to find an expert. Maybe a testing agency to check moisture contents, etc.