I only know what I read on the ECN BB but I gather NMD90 is essentially NM-c and NMWU is UF up in the great white north.

Precisely what that code panel is looking for - is that the decision be made by the local AHJ.

There are other things to consider. If it is considered a damp location, then floor trusses and/or framing might possibly have to be pressure treated. Now we are getting into a cost factor.

I'm not saying that I'm against writing it into the Florida Building Code - that this location be considered a damp one. But I'm not saying that I'm for it, either. I think that you will never get it written into the NEC. Try and see the response you get back from the panel.

Exactly correct Greg, those are the terms for romex and UF in Canada. Nick's response was right out of the Canadian Electrical Code, table 19.

I was merely quoting what someone else said.

After thinking about it over several days, I'm going to change my answer. I do NOT think it would be good if we can blanket all crawl spaces as "damp location." Lets use my house as an example:

Structurally, my house is wooden, not block. But it sits on block piers, poured solid. Around the perimeter of the house, the framing sits on a 3-1/2 foot concrete-block stem wall, that is poured solid. There are no openings, save for the FEMA-required venting, which isn't very much.

I call this crawl space the "black hole" and I can't stand going under there because of the trolls and bogeymen that live down there. If I see one, I may have to kill it, so I'd just as soon avoid the altercation altogether.

HOWEVER -- when I DO embark into the dark depths of the black hole for one reason or another, I can assure you that it is very dry. The floor trusses are dry. The lumber (bracing) is dry. The floor is not poured, it is dirt. The dirt is dry. It is not damp.

Soooooooo, I will have to disagree with those who say that ALL crawlspaces should be damp location, or that the code language should be more specific. I still say it depends whether or not rain can blow in. It depends upon the physical characteristics of the crawl space itself. So I AGREE with the code panel (this is rare) for NOT making the language more specific! I think NEC covers the issue just fine. It is an AHJ call.

PS - Now I will add - that I believe it to also be wrong to blanket-label all crawl spaces as "NOT" being damp location. Like I said, I believe that it depends upon the physical characteristics of the crawl space itself, in my opinion. Other than that all I can say is to please never, EVER, feed the trolls.

Here's just a thought, I normally find that crawl spaces under houses are dry, other than the outer 2ft around the edges where there is no underpinning , no stem walls, just open to the weather

Nick, if your house is truly a stem wall house, why didn't they fill the box with dirt and pour a slab floor? That is the way they build stem wall houses over here.