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8 Answers

Gas heated steam radiator system


Asked By Daniel Herskowitz | Dec 5 13
3 Answers

All-electric vs. natural gas in Zone 2

I'm building a house in Houston, Texas. It will probably be a 'pretty good' house - dense pack cellulose and exterior rigid foam installation with an encapsulated attic and targeting an ACH50 of <3 with an ERV system for ventilation. I will have a sizeable solar PV array on the roof - 6-8 kw so I have been debating whether to use natural gas as in my current house for multiple appliances or go all electric. Pros and Cons as I see them are:

Benefits all electric:
No standing monthly charge of $25 for gas since consumption is below threshold 9 months of year

Asked By user-6822325 | Apr 22 17
3 Answers

XPS Foam 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
0 Answers

Can Straw bales be used on the exterior of a shipping container home?

I am interested in building a shipping container home. Insulation is one of my biggest concerns. I have read a lot about the benefits of straw bales. I am very interested in using this as the exterior insulation, but have not found any info pro or con. Any help will be very beneficial.
Thanks for your info.

Asked By OrrinH | Apr 23 17
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

March for Science

I'm sure that many GBA readers spent yesterday at their local March for Science protest. My wife and I, along with several friends, joined researchers, academics, middle-school science teachers, and lots ordinary people who care about the planet (and who use accepted means of separating truth from falsehood) at one of the hundreds of marches that happened all over the world yesterday.

Lots of good signs. Among my favorites: "I can't believe I'm marching for facts" and "Knowing Stuff is Good -- Seriously, why do I even have to march for this?"

Asked By Martin Holladay | Apr 23 17
1 Answer

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
3 Answers

Hip roof in Zone 6A

My client is a builder who has already completed the exterior siding and roofing of a new house in coastal Maine (zone 6A). The hipped roof and 2x6 walls have no exterior rigid insulation and no air space between cedar shingles and Typar. Walls: 2x6 with R-21 batt (John Mansfield), 1/2" CDX, Typar, cedar shingles. He plans to install shiplap hemlock paneling to the interior. Roof: Hip, 6 in 12 pitch, 2x10 rafters into (2) 11 7/8" hip rafters. Also has two dormers.

Assuming we go with an unvented assembly, how do we best achieve a vapor seal?

Asked By user-6825743 | Apr 22 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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