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3 Answers

Fiberglass-backed polyiso got wet, now moldy on surface: to keep or not to keep? Remediation?

A few months ago I chatted back an forth with Mr. Martin Holladay about my project... I have progressed on it since then, but have ran into an unforeseen problem. Let me bring you up to speed:

I am building an apartment underneath a lean-to roof coming off of a post-frame shop building in climate 3. I purchased some used poly-iso foam boards to use as insulation on the underside of the existing metal roof. At this time I have reached this point (Layers shown from top to bottom):

Metal roof
2x4 purlins (with subsequent 1.5" air gap)

Asked By John Peeper | Apr 23 17
2 Answers

Double sheetrock + green glue + Membrane

I am going to be using mineral wool, a certainteed membrane, and possibly 2 layers of sheetrock (1/2" or 5/8") with green glue between them. Is there going to be any problem with this design in terms of the membrane's performance? I don't want moisture problems by using 2 layers of sheetrock + the green glue.

Asked By Ralph S | Apr 24 17
18 Answers

Warmboard with Ductless System?

Newbie here, so pardon my ignorance.

We are about to start designing a home in the DFW area (Zone 3).
Home will be a 2-story open concept with about 5,000 to 5,500 SF, properly insulated for the area. Despite the size, plans are to go with about 20 KW of grid-tied Solar Panels with a Powerstation 247 system.

Wife wants "Warmboard" as the heating source for at least some of the areas. I would like to have a VRF Ductless System for cooling and heating. Is there anyway to marry the two so that we stay "married" ? :-)

Asked By Rodgo | Apr 19 17
8 Answers

New house build, SIPs?

New member here, we are planning to build a new house this summer and I'm exploring my options for wall systems. I plan to do the framing myself. House will be roughly 2500 sqft in Ottawa, Ontario Canada. Not the coldest place to build but not far off, and just for kicks it gets pretty hot and fairly humid here in summer as well.

Asked By Lance Peters | Jan 15 17
0 Answers

Standard (non-custom) window sizes?

In the interest of getting the "most bang for my buck," I have been trying to find "standard window sizes," as opposed to what is generally advertised as "custom" windows... Perhaps this is something that is available in high performance windows, perhaps at widths which correspond to common framing widths such as 24" OC, 16" OC, etc. I would be happy to design around these parameters, but it seems that most high performance window manufacturers also tout "custom sizes." Does anyone have a lead on standard high performance window sizing?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Apr 24 17
3 Answers

XPS foam on exterior side of window and door headers

I think have seen a similar question before but wanted to refresh.

Assume building a 2x6 wall. Using Mineral Wool for insulation (which means a smart membrane on the interior side of the wall). When framing headers for doors and windows almost ALL of them only need double 2x8, typically with ply sandwiched to make them flush with the stud depth. In 2x6, simply 3 pieces of header lumber are nailed together to get the 5.5" thickness of the stud.

Asked By Nicholas C | Apr 23 17
9 Answers

Gas heated steam radiator system


Asked By Daniel Herskowitz | Dec 5 13
19 Answers

Need sizing advice on a minisplit unit

I installed a Mitsubishi FH12NA in summer of 2014 when they first came out. I live in inland San Diego, and it can get hot, like 10-15 degrees hotter than the coast.

My condo is a studio and is only 420 sq ft. I'm on the upper unit of 2 stories. I face East and South. I have a skylight and dual-pane windows. Building is 1978 construction.

My Mitsubishi is weak. I set the temp and it will barely do anything. I have to set the temp to 61 and manually put the fan on high for it to do anything. Even "powerful" mode is weak.

Asked By aypues | Mar 16 17
18 Answers

Insulating new construction home with no exterior rigid foam

Okay smarties, here is my scenario:
-I am Building a new home that is currently in the framing stage. 2x6 studs with Forcefield Sheathing (essentially same as ZIP).
-I am in in Climate 5 (iowa)
-My home is a California style architecture, 1.5 story, pitched roofs (now I realize why this is better suited for CA-vented roofs better option in Midwest!)
-My initial goal and how I came across these articles was to prevent mold (still is)

Asked By user-6809983 | Apr 9 17
2 Answers

Infinite R phase change materials

I am looking into using phase change materials in my new home to reduce temperature variability. It looks like National Gypsum's use of BASF's Micronal PCMs in its Thermacore drywall has never gotten off the ground.

I found Infiinite R via Google, but can't seem to find any independent reviews.

Does any one have any insight on this product or viable PCMs?


Climate Zone 3A - Upstate SC

Asked By Pnjfksx | Apr 23 17
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