TOPIC: Vapor barrier in crawl space in California

I know about vapor barriers under slab foundations but is one required in the crawl space of a California home? I searched my IBC,ICC, and IRC code books and I did not find that a vapor barrier is required in a crawl space, only cross venting.

What is the difference between having a vapor barrier under a concrete slab and one in a crawlspace?

They both retard moisture.

It really doesn't matter what IBC, ICC or IRC says about anything. If you have moisture, you have moisture. A way to control moisture is with the vapor barrier. It makes no nevermind if it's a code requirement or not, as a home inspector you are there to observe and report the conditions that exist. You don't need the municipal code inspectors permission to report anything in your inspection port. If it is generating a "significant deficiency" in the home, it's your obligation to bring it out.

If there is no vapor barrier under the house, reported as such. If there's no moisture condition observable from past or present conditions, note that as well. It's up to the owners/buyers of the property to determine what they want to do. It is not your responsibility to "make" anyone make any type of repair on the property and it is not the responsibility of the seller to make any upgrades, regardless if they are building code requirements are not.

They are not even required to repair anything if there was 1 foot of water in the crawlspace at any time, they simply must disclose it.

Don't get all caught up in enforcement. Simply observe and report.

General contractors will tell you all day long that " it passed building code". Nine times out of ten if we go back to the building code official and tell them what we found, they will come back and make the contractor fix it if you identify it.

Thanks David, that is excellent advice.

Mike

General contractors will tell you all day long that " it passed building code".

The other line I hear all the time is "I've been doing this for twenty years and I've never seen that happen". That's what I get told when I call something out and someone has the contractor call me to debate my report. I don't really care if you have done roofing for 20 years and have never seen a leak due to an exposed nail head.  I HAVE.  And no court will except this defense “The contractor said it wouldn't happen so I didn't mention it on my report.”

I agree wholeheartedly with David's post, especially the point about the IBC, ICC & IRC. I probably couldn't tell you the specific rules, guideline or codes for any state or municipality on most issues, but I do know what the best practice in my area and climate. I have come to understand that often repeated phrase "home inspectors are not code inspectors" better every year. The vapor barrier is a perfect example: Moisture causes mold, vapor barriers reduce moisture, recommend the vapor barrier.  Code or not, it's the best practice (or one of them) and it protects me and my client if I recommend it.

Thanks for chiming in, I appreciate the feedback and I agree with both of you.

Mike

General contractors seldom see what we see 5, 10, 15 years down the road. Their opinion is generally worthless.

"I've been doing this for twenty years and I've never seen that happen".
My reply is; "it doesn't matter how many times you do it wrong, it doesn't make it right"!

"It passed building code"

I love this response when out front there is a sign "quality built homes by…"

Yes, a quality built home, built to the minimum building standard!