flightcrazed

You got it!

Thanks for the reply Jim. This is my interpretation as well. On this project specifically, County Fire has requirements for maintaining 100' defensible space, the first 5' away from home of which are "most important". To me, that, combined with non-combustible/ignition resistant covering, should be sufficient for reducing the ignition likelihood of the wall during a wildfire (as you say, the intent) and meet the code requirements.

Thanks Alan. I have asked the County (Plan Checker) to answer the question but he is either on vacation or worried about responding :). I realize my mileage may vary depending on the inspector but feel like if my case is strong enough (plan check approved, code referenced, etc) then I should be good without having to tear down siding and adjust after the fact. Appreciate your inputs as always.

I mean, if we want to get technical...exterior wall covering includes Siding. And your highlight refers to "finish" materials defined as: So, there's that....

Hello, Anyone with experience putting rigid Polyiso board over sheathing and covering with Metal siding? Curious if this is a best practice (using the polyiso as WRB) or if better to put a barrier between it and the wood sheathing and/or the metal. Thanks! Shawn

Hi all, hoping you can help me. I'm having a dispute with a contractor on whether a 1hr fire rated wall assembly or just a non-combustible covering is needed. The project is type VB, R3 use in a WUI area and not located within 125' of another structure or property line. I am interpreting 2022 CRC R337.7.3 to mean that only the non-combustible covering is needed (metal in this case). Am I missing anything?

awesome, thanks Alan. I'll check in with those guys. Do you have good experience with their products?

Thanks Michael, appreciate that. Honestly, i don't really find peace in either scenario: venting in a high fire area, or now unventing and having water problems. Though pulling the UDL50 and giving a little breather to the top doesn't sound too bad at this point. Underneath the roof deck, i'm a bit undecided on insulating at roof plane or ceiling plane now. Original insulation plan was 6" polyiso on top (none underneath) to keep the unvented design but since that has changed to 2" on top, I am thinking R30+ fiberglass batts in either roof or ceiling plane. The struct OSB does have a perforated reflective barrier (ceiling side). I think if i put in ceiling plane I'd have to ventilate.

Thanks for the reply @Alaskan_Son. Sorry, I didn't share full context, but there is a 2" layer of polyiso above the structural OSB followed by another 7/16 osb as a covering attachment layer. It is this attachment layer that has the UDL50 on top. The design principles for the unvented roof is how i arrived here...but seems like perhaps a metal roof shouldn't be installed above an unvented assembly (all of the "recommended" underlayments are low perm in nature, i.e. Titanium FR, Polystick XFR) if i'm understanding you right?

Awesome, let me know what you find. i'm still digging around as well and will let you know what i come up with

looks like the densdeck version might work...at least it's been tested by some metal vendors. i was hoping to find something a little simpler to install like 30# felt or similar

Hi all, working on a project that was originally designed to be an unvented attic with asphalt shingles. Plan is to change to metal, however the underlayment (Titanium UDL50) has already been laid and is only Class A under asphalt. I've found that Versashield can bring metal to Class A but not intended for unvented assembly. Anyone know of another product that could be laid on top of UDL50 to reach Class A for metal? I've found Atlas FR10 but all the documentation seem to support a commercial roofing system. Much appreciated!

Hi all, working on a project that was originally designed to be an unvented attic with asphalt shingles. Plan is to change to metal, however the underlayment (Titanium UDL50) has already been laid and is only Class A under asphalt. I've found that Versashield can bring metal to Class A but not intended for unvented assembly. Anyone know of another product that could be laid on top of UDL50 to reach Class A for metal? I've found Atlas FR10 but all the documentation seem to support a commercial roofing system. Much appreciated!

Genuis! Thanks for the reply! Yep, "existing" meaning by the time I go to pour concrete it would be existing.

Hi all, I'm designing an RCA barn and wanting to design the floors/walls to allow for a future 4" concrete floor sitting on top of (what would be) existing road base. I'll have continuous footings. Would I want to design a 4" high stem wall as thick as the wall in Chief? Or factor it in with either the floor finish or structure features? Much appreciated!