# DWV under slab dryer duct



## retire09 (Oct 1, 2012)

I have a contractor wanting to run the dryer vent under the slab in DWV.

Has anyone heard of a manufacturer that allows this?

It has 4 90s and the entire length is one big trap for moisture and lint.

He insists he has done this in other jurisdictions.


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## Gregg Harris (Oct 1, 2012)

retire09 said:
			
		

> I have a contractor wanting to run the dryer vent under the slab in DWV. Has anyone heard of a manufacturer that allows this?
> 
> It has 4 90s and the entire length is one big trap for moisture and lint.
> 
> He insists he has done this in other jurisdictions.


 Not allowed the temperature rating on the PVc is 140 degrees F and the requirements on the dryer exhaust is 440.


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## fatboy (Oct 1, 2012)

Not allowed;

M1502.4.1 Material and size. Exhaust ducts shall have a smooth interior finish and _*shall be constructed of metal *_a minimum 0.016-inch (0.4 mm) thick. The exhaust duct size shall be 4 inches (102 mm) nominal in diameter.


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## jpranch (Oct 1, 2012)

Is that anything like a contractor wanting to use Timberstrand for sill plates on a monoslab for a new restaurant? Got the same story about other jurisdictions allow it. Ya right.


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## zigmark (Oct 1, 2012)

Not sure when two wrongs started making things right.

So you're the guy letting them do that jp.... lol.

Goes to show ya that no matter where ya go the arguements never change.

ZIG


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## pete_t (Oct 1, 2012)

TIMBERSTRAND LSL TREATED SILL PLATE

http://www.woodbywy.com/walls/w_TimberStrandLSL_sillplates.aspx


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## mtlogcabin (Oct 1, 2012)

jpranch said:
			
		

> Is that anything like a contractor wanting to use Timberstrand for sill plates on a monoslab for a new restaurant? Got the same story about other jurisdictions allow it. Ya right.


http://www.woodbywy.com/walls/w_TimberStrandLSL_sillplates.aspx

http://www.woodbywy.com/literature/TJ-8100.pdf

http://www.icc-es.org/reports/pdf_files/ICC-ES/ESR-1387.pdf   See Sections 3.3.1 and 7.2


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## jpranch (Oct 1, 2012)

The type of Timberstrand proposed was not their treated product. Heck, treated manfactured lumber has been around for a lot of years. I just sent the contractor the requirements from the 09 IBC and told him that if the product meets these requirements then he is good to go.


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## JBI (Oct 1, 2012)

GBOT...

The code is specific, but would allow compliance with manufacturers specifications as an alternative. That would be both the dryer manufacturer and the pipe manufacturer.

The four elbows would leave only 5' of pipe prescriptively permitted.

But I do have to ask... would that be four left turns? or four right turns?


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## codeworks (Oct 2, 2012)

when i run into these types of situations, i usually say something like "i'm not familiar with   what "other jurisdictions do", and that doesn't really have any bearing in this one. this is what the code says, and if you can show me evidense as to why  we should deviate from that standard, we'll look at it and make a decision ,otherwise, it's a no go.


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## BSSTG (Oct 2, 2012)

codeworks said:
			
		

> when i run into these types of situations, i usually say something like "i'm not familiar with   what "other jurisdictions do", and that doesn't really have any bearing in this one. this is what the code says, and if you can show me evidense as to why  we should deviate from that standard, we'll look at it and make a decision ,otherwise, it's a no go.


Codeworks, you are a really nice person. I just say your "your in XXX now, we don't allow that"

BS


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## codeworks (Oct 2, 2012)

no, actually thats not true. i use those terms )most of time) to avoid backlash from contractors back thru higher ups. i can be rather prickly at times


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