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0 Answers

Replacing traditional masonry chimney with metal chimney pipe

Hi all,

I live in 1950s ranch in Chicago. We've invested a lot into improving the efficiency of the home: 95% eff radiant heat, indirect DHW, minisplit for AC, lots of airsealing and the new low carbon CC sprayfoam at our roofdeck. We are now looking to replace our roof (keeping asphalt). We've hired a roofer but he won't start until we rebuild the chimney. The brick is crumbling from when the mechanicals used to pump moisture through it (they no longer do).

Asked By Brian Gray | Mar 18 18
3 Answers

Attaching Porch Ledger to House

I'm currently in the design phase of a modern cabin. I will have a porch roof that extends about 12 feet out and covers a deck. The problem is I don't have a rim/band joist to attach to (the porch ledger will be located about 11 feet up on a 14 foot wall). So I'm wondering what the best practice is in this situation. It seems like attaching to studs won't do the job. Can I just install 2x10 interior blocking between my studs to attach to?

Asked By rodrob15 | Mar 11 18
10 Answers

Can you spray closed-cell insulation over mineral wool insulation?

New house design with 2x4 outer wall with mineral wool then 1 inch gap then 2x3 inner wall. gap and 1 inch of inner wall sprayed with closed cell

Asked By Joseph Isherwood | Feb 26 18
4 Answers

Indoor air intake into high-efficiency tankless water heater

I have the option to let our new tankless water heater intake indoor air (it will be installed in a semi-finished basement), or intake it from the outside. The manufacturer seems to be OK with either approach.

What code would/does apply in this case?

PS. Our furnace/boiler intakes indoor air as currently installed, so logic tells me I could do the same with the tankless water too!?

Asked By Rocketscientist51 | Mar 2 18
2 Answers

Can the granular fill used for soil gas mitigation be compacted or is it self-compacting?

In order to maintain a complete thermal break I want to place 1 1/2" of xps under my slab. The 5" slab acts as footings for interior bearing walls ( floor load only). The XPS easily exceeds the required compressive strength (even for foundation footings) but normally fill under any footing has to be compacted. I suspect that the granular fill (less than 10% fines) is considered self compacting. If compacting is required it could compromise the permeability? Alternatively I could place concrete footings below the foam layer but that would be a lot of work and expense if not required!

Asked By Dave@terrace | Feb 26 18
1 Answer

If UL-approved aluminum tape is applied to the return side (bottom) of air handler to filter base, is mastic still required?

A co worker and i disagree on this mastic is required where condensation will allow tape to peel. But condensation does not occur between the filter base and air handler on an upflow system. Correct?

Asked By Acrescue Tech | Feb 21 18
20 Answers

Cold climate basement insulation and code questions

I live in SE Wisconsin (Climate Zone 6) in a 1930s house that has a currently unfinished cinder block basement with a concrete slab floor. The basement is unconditioned but stays at or above 55 degrees in the dead of winter. Basement walls are 95% below grade, and there are some small windows at the top of the walls. The house is heated with hot water radiant heat but there are no radiators or other heat / HVAC sources in basement.

Asked By Navigator16171 | Feb 19 18
3 Answers

Basement vapour barrier


Asked By user-6994354 | Feb 17 18
4 Answers

LSL Framing

I'm planning on building a small cabin with some laminated strand lumber (LSL) framing. I'll be doing 24 inch on center, so I'm going with LSLs for some additional strength. Straighter walls and easier installation are added benefits too. LSL lumber is very expensive, so I'd like to just use them for the studs and then use standard dimensional lumber for top and bottom plates. I'm trying to find a cost effective way to incorporate some of the benefits of LSLs. I'm thinking that warping is less of a concern for the top and bottom plates.

Is there any concerns with this approach?

Asked By Rodrob15 | Feb 14 18
2 Answers

Can I get away with a moisture barrier and unfaced batts in an attic?

I'm in zone 2, and I'm getting mixed information from my local building supply. Does code allow me to install plastic sheeting between attic rafters, before unfaced insulation batts? Wouldn't this help prevent condensation by restricting air flow to the roof sheathing?

Asked By Rob Harman | Feb 2 18
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