You're currently under the 2006 International Code. I don't believe this is on-line anywhere. Try your local reference library. However, Building Science Corp.s recommendations are usually made with reference to existing Codes. Specifically, here's what they say about foam insulation in basements.

A new neighbor says I need to leave space between the XPS and framing (and perhaps should have left space between the XPS and drywall) OR should have plastic in between.

Unless your new neighbour has a Ph.d in building science, I'll stick with Dr. Joe's recommendations! Because everyone lives in a house, everyone thinks they're an expert.

However, you are right that the local inspector might insist on a 6mil barrier to the warm side of the fg. I've been required to do that on two installations--XPS on the foundation, fg between the studs. Building Science says it's unnecessary but is of no harmful effect.

If some inspector says you have to tear off the drywall to put in the unnecessary barrier, you can still appeal to a supervisor in a pleasant manner, using Building Science materials. Remember, you catch more flies with honey than vinegar.

I see you're a sociable guy. But sometimes it's best to leave the chats to on-line!

Good luck.

you really know your way around that site..I was on there a few times and never ran across that. To me the concept of the 6ml plastic makes no sense but if there is no harm I could just put it up. Of course the closet areas where I used the slotted stuff are already done and do not have plastice between the drywall that is adhered right to the slotted XPS nor are they R10 either....I think the the 1.5" xps was an R 7.5 and the drywall maybe adds an R1. Funny, I bet I still get more insulating factor here than someone who framed in front of the wall and put R13 in!

I found out area has now taken to farming out electrical inspections to a 3rd party. Hopefully they only look at 'electrical'. If I read you comment correctly perhaps I should just finish the framing and just have the electrical done and inspected and take it from there.....ie leave the chats on line....knowing what I did is safe and sound.

What about the fiberglass insulation? Does this have to be unfaced? Most places have only paper-faced insulation in stock. Also, does the type of drywall matter? I'm doing a similar install with 1" XPS against the wall, then a framed wall against it. I planned to put the wall tight against the XPS, but the framer did two walls already and left a half inch gap (not sure why).

See page 10 in link below.

The paper facing, designed to inhibit moisture flow into the wall, will also slow the necessary drying to the interior in the portion of the basement that is above grade.

The 1/2" gap is irrelevant. Place the fg between the studs and against the XPS.

Here is a link that might be useful: Basement Insulation Systems

Does the type of drywall matter?

I've only ever used standard 1/2". Here's a GW thread on paperless drywall. See link too.

It always seems to me that it would be better to cure the water problem at the source. In the case of a flood, the paperless drywall won't likely perform any better than paperfaced types.

Here is a link that might be useful: Paperless Drywall