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3 Answers

Do I need to cover XPS in an attic?

I know codes vary from town to town but I'm looking for the general code requirement/interpretation for this. I have used R-10 2" XPS for the interior of basement walls. I know that it must be covered with drywall or another similarly accepted material for compliance and I have done so. I also have learned that the exception is between floor joists at the rim joist and have benefitted from this exception...wouldn't that be a pain of a detail! I now have to build an enclosure that had never been built for a fire box that protrudes into the attic over the garage.

Asked By Tyrone Powell | Jun 22 15
4 Answers

Insulating the Interior of Poured Basement Walls

This picture is from building and shows an ICF foundation with insulation under the slab. My question relates to the interior wall plane where the floor slab meets it. Does the code require that the slab make physical contact with the concrete wall? If it does, how do code officials deal with situations like this one with ICF foundations? I wanted to have a similar insulation setup on the interior with poured walls. Prior to pouring the floor I would lay rigid foam along the ground and up the wall - thermally isolating the slab.

Asked By Brian W | Jun 21 15
1 Answer

Is this 2012 code already enforced for TX ? - whole-house mechanical ventilation system

Is the requirement of "whole-house mechanical ventilation system" for Code 2012 already being enforced in TX ?
Is it mandatory in the state of TX now ?
If so, can you send me copy of that section for Code 2012 or which website to locate it please ?

Thank You,

Darla Kay

Asked By DARLA KAY | Jun 18 15
3 Answers

Is tape permissible between framing and the party wall for air sealing?

We are building a Passive House duplex and have encountered bunch of air leakage around party wall. We don't have to reach Passive House standard for each of the units separately, only as a whole building. But currently, our party wall does not have any air seal crossing between two units. This opens up the possibility of air getting in somewhere at the top end of it (at the roof) and traveling down to edges of the party wall touching the whole building enclosure/exterior plywood. We have difficulty sealing these vertical contact points due to other framing being in the way.

Asked By Lucyna de Barbaro | Jun 12 15
2 Answers

Toilet stack alternatives

I've recently realized that air admittance valves have generally become
more permitted by code and help reduce the number of roof penetrations,
but they likely still won't do for a sealed system [on-property septic]
as any positive pressure has to have *somewhere* to go. Thus, as far
as I know code only permits AAVs for branches but not the main stack;
there has to be *someplace* for the sewer gas and its attendant
condensation to escape. [Is that also true for systems piped into
city sewers, which would eliminate the pressure problem?]

Asked By Hobbit _ | Jun 10 15
2 Answers

No footing, no drainage?

Yesterday I was excavating a corner of my house to add Roxul to the exterior of my slab on grade foundation walls to help with my hydronic heat problems.

To my amazement, I found a section the foundation wall that has no footing. It is where the garage footing meets the house foundation wall. There is a corner and the house side of the foundation wall is missing a footing for about 2 feet. After this you can see the wood they used to form it go back below grade where I'm assuming a footing starts for the rest of the wall.

Asked By Michael McArdle | May 27 15
9 Answers

Can I reuse single-pane steel sash windows?

A client would like to restore some window openings that were bricked-over by a previous owner. The original single-pane steel sash casement windows had been stored, and are in excellent condition. The building department views these "restored" openings as "new" openings, and requires compliance with the energy code, i.e. window U-factor of 0.30 or better. (The default value for these windows is U=1.20 per Table R303.1.3.)

Asked By Robert Drucker | May 21 15
6 Answers

Vinyl siding renovation


Asked By Chris Felker | May 14 15
3 Answers

R-38 ceiling and spray foam

If one sprayed 5" of open cell spray foam on a ceiling area, that would equal to around R-17.5, correct?

Now code requires R-38 minimum for the ceiling in this area. There is no "performance value" of R-38 in 5 inches of open cell spray foam, right?

That would be a marketing line bunch of nonsense as 5" of open cell is R-18 avg. and anyone claiming it is performing like R-38 is lying. How would the code department buy into this nonsense?

Asked By Peter L | May 15 15
2 Answers

Basement perimeter wall construction

My basement has a full perimeter sump pump; drainage mat on wall from 1 foot below ground level to loop into the plastic cove that empties to the sump drain below; limestone foundation walls; penetrating sealer on the concrete floor.

I plan on installing light steel perimeter walls where no steel will touch the limestone foundation walls. Closed cell spray foam, treated with a fire barrier, will be installed professionally after plumbing and electrical runs are completed.

Asked By Donna Agah | May 15 15
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