New construction floor joist issue!

[A930Rocket]

Well, an ordinance I didn't know about has bitten me on the ass big time.

Turns out that everything below the first floor decking (floor joists) has to be moisture resistant treated wood. This can be pressure treated wood or natural resistant wood.

Of course, I used web joists made of pine like I've always done.

Now the big question:

Anyone know of a way to treat the wood to make it moisture resistant? The building dept said there was a product but he didn't know the name.

Any ideas, besides firing myself?

[wswartzwel]

used to be a product called Penta.

[craigster59]

You might try this. We used to use it on wood posts before placing them in the ground.
Wolman 5-gal. CopperCoat Green Below Ground Wood Preservative-1902A - The Home Depot

[DanielDudley]

I'm going to go out on a limb here, and suggest Thompson's Water Seal. Name pretty much says it all.

I'd personally like to see it treated with boric acid, but that isn't what he asked for. All the guy really wants is for you to provide him with something he can sign off on. If you bring him a can of Thompson's, and show him the label 99% chance he will say yes.

[GH85Carrera]

One of my good friends has a saying that sounds like it fits here.

"There is no good fu**ing, like a good self fu**cking.

I have no answers for you I just wanted to pass on some wisdom from a friend.

Good luck finding a way to treat the wood in place that is not toxic to long term residents of the house.

[look 171]

If there's such thing, I like to know about it. Tile guys use Red Guard. Its water proof, but I don't know how long it will stay waterproof when its not covered? There are similar products out but their names escape me. I am not a big fan until they have earned some time under their belts as a proven waterproof material. How about w rapping it with builder's paper, Tyvek house wrap, or smear roofing tar over the surface of the joist? Those are more then water resistance.

[billybek]

Could you put in a vapor barrier and skin with a moisture resistant product?
Wouldn't hurt to ask an inspector where you live.

[A930Rocket]

Thanks for the ideas. Keep them coming.

For good or bad, I'm the one living in the house when finished.

I've talked to my structural engineer and my lumber supplier. Neither one had heard of the rule or had an answer, but are looking into it.

I'm going to ask Sherwin - Williams if they have a spray on product.

As a last resort, I'd have to swap out the floor joists. I imagine it won't be cheap.

I'm going to call the head of inspections tomorrow for advice.

[1990C4S]

Spray foam is insulation and a vapor barrier...

[porsche4life]

Thank god it's your own house and not a customers. Sue yourself!!!!

[herr_oberst]

I've used stuff just like this to treat cut ends of PT wood posts when I build fences....

Rust Oleum 1904 Green Wood Preservative Quart Green at EssenntialHardware.com



Good luck. Sounds like you just got hit with the "Stupid Tax" which I have paid more times than I care to ever admit....

[look 171]

I ask the inspector and go from there to satisfy code. If you want to really waterproof it, then skin it with house wrap or a similar product

[dennis in se pa]

Whoever approved the drawings (building inspector? Code engineer?) should have pointed this out to you. They always asked me all sorts of questions until they got to know me. I would go back to them and get them to help you find a solution. Seems like a silly requirement as long as the joists are above ground level. Is this a new requirement? Cabo? Boca?

[dad911]

That does not make sense. Are you over a crawl or basement? If a crawl, can you include the crawl space in the 'conditioned area' by insulating the walls? Is there a vapor barrier under concrete on the floor?

Edit - Looks like SC has adopted 2012 IRC. http://publicecodes.cyberregs.com/icod/irc/2012/icod_irc_2012_5_section.htm

I don't see a requirement for Treated joists unless they are in contact with ground or masonry.

[intakexhaust]

A930Rocket- Define first floor decking. Is this a floor exposed to the outside, as in a deck? Or is this a first floor above a crawl or basement concrete walls?

If its an exterior deck, naturally all of it should be a treated rated wood.

For an exterior wall, the bottom plate should treated lumber plus have sill plate foam between that and the concrete.

Also, in the case above some areas also require a finished basement and walls to have treated / green lumber for the bottom plate only, but no sill plate foam.

I do know of an individual who framed up his finished basement without a treated lumber bottom plate. Inspector gave him a pass only after he applied Thompson water seal. That in itself was stupid because there was no way to actually get the Thompson's underneath.

[intakexhaust]

While on topic of joist, hangers can be a prick subject by inspectors. Some require hand nailed Teco / tico galvanized type. Others won't accept clipped head and or discretionary on using a dedicated joist hanger power nailer. Always wise to your homework first or a quick call to an inspector.

[A930Rocket]

This is new construction on a crawl space in an "A" flood zone. I should have mentioned that as an important point. All exterior wood is treated wood.

The town requires has a plus 1' rule, which means that I need to add 1' to the 11' above sea level zone I'm in. The finished first floor elevation has to be at 12' or above. I'm at 12.33'.

What they are saying is that if the framing isn't above 12', it needs to be treated wood or made of natural decay resistance wood. To complicate things, I can't be above 38' from the ground to the ridge. Thus I wanted to make sure I got above 12', but not too high to keep it below 38'.

There are several ways to treat the wood, but I would think it needs to breath and I wouldn't want to completely encapsulate the wood.

Here's what It will look like when finished.

[MRM]

Rocket, I have unique knowledge of South Carolina building codes, having spent a few pleasant years of my life working on the lovely Bristol Condominiums, located at the mouth of the Ashley River, built in the early 2000s and rebuilt at the turn of the decade, as the marketing brochures will tell you.

Anyway, it's not clear to me that the building official is citing the right code section to you, or that it applies to you. I think he is confused. How far are you from the ocean? Which Miami-Dade Notice of Acceptance did he quote to you for your windows? I assume you have to have windows that are designated coastal product with small and large missile resistance. If not, your inspector is off base. If you do, he still may be off base.

I think he's confusing the requirement with below grade requirements. The term moisture resistant or water resistant is notoriously difficult to define in the code. For several years OSB board was considered a moisture resistant building material, which allowed the use of a single layer of 15 lb felt for the drainage plane rather than two layers of Grade D building paper, and anyone who knows anything knows that OSB soaks up water like a sponge. Note that water resistant and pressure treated are two very different things.

Anyway, this is a long way of saying that what you need to do is ask the local building official to cite to you the actual ordinance or code section that supports his interpretation. Both report back here and ask your engineer or design professional to review the building official's opinion. I don't think he'll be able to point to an ordinance that has effectively adopted the code to say what he thinks it did. If he is able to convince you that his reading of the law is right, hit it with Thompson's water sealer and dare him to prove that it isn't now water resistant.

As far as I know water resistant isn't a defined term in the code. Therefore anything that resists water will make wood water resistant. Play nice with the petty bureaucrat who is the local building official and let us know what he says when you ask what section of the code says what he claims, and defines water resistant.

[A930Rocket]

MRM - I'll definitely update tomorrow. I'm not sure if is a local or IBC ordinance.

I'm not near the ocean, but I am close to the Wando river, in Rivertowne, in Mount Pleasant.

Hopefully I got the nomenclature correct from him, but I know he said pressure treated wood or naturally resistant wood.

Hopefully it's just a matter of spraying something on the joists. If it were to flood, it's not like it's going to be under water for weeks.

[MRM]

If he's really looking for pressure treated wood instead of water resistant wood, you're in trouble because that's a defined term in the code. Naturally resistant wood means cedar or similar wood. Maybe you want to change your joists to teak?

But the building code has to be adopted by the local municipality or state to be effective. If he can't show you a cite to the code he's referring to and he can't show where that part of the code was adopted by the municipality, it doesn't have legal effect. However, even if the code has been adopted as he suggests, he has the authority to grant waivers to the strict interpretation of the code. Don't fight with him or he'll inspect you until you're reduced to grade level, but do ask him what an acceptable alternative would be. Don't be surprised if he suggests Thompson's Water Seal.