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3 Answers

Mitsubishi remote thermostat and warranty

Hello All,

I have been lurking for awhile, as I usually find my answers through searches, but having a new Mitsubishi Hyper Heat system installed, I thought of a question for which I can't find an answer.

I had it installed by a Diamond contractor (primarily for the warranty coverage aspects), and the inside units have the usual handheld remotes.

Asked By Wayne Yamamoto | Sep 30 16

0 Answers

Single versus double header for energy efficient framing.

There are two headers that I could use for a short span in a 2x6 wall: one 2x10, or two 2x6's. With the 2x10, I would fill the open space with cellulose on the inside. With the 2x6's, I would sandwich in a 2.5" layer of rigid foam. Since code would require the 2x10 header to be boxed in with 2x6 plates, it seems like the doubled 2x6 header will present less of a thermal bridge and use less wood.

Am I missing anything? I've seen a number of sources suggest single member headers to improve efficiency, but the code requirement for extra plates seems to make them worse.

--John

Asked By John Ranson | Sep 30 16

6 Answers

Most efficient use of 3/4" polyiso on exterior (polyiso is foil faced on both sides)

My home is standard built- 2x3's 16" oc w/craft faced fiberglass ins not very well installed( gaps,etc.). I have enough 3/4" f f polyiso to cover it. FH's recent articles indicate Roxul batts would be best way to insulate, but I already have the foam.

Asked By Victor Brown | Sep 29 16

9 Answers

Minisplit Design for Whole House

Hello, first of all thank you GBA for all of your articles, I have read many and found them to very helpful and interesting.

I am renovating my house (in Tampa, FL) and installing a new AC system, I will be installing minisplits most likely DIY, but will also talk with installers. I want to see what GBA users recommendations are for how I should design my system.

Asked By Jimmy Black | Sep 29 16

3 Answers

Basement – Best way to eliminate musty smell / mildew/ mold etc

I am new to the forum. Thank you for your suggestions.
Purchased a lake house last year. The basement (see attached picture) is musty.
Looking for suggestions / products to redesign the room and clear the air.

My thoughts were to:
Purchase a dehumidifier
Purchase fan(s) to circulate air internally
Install a fan with a timer in the back wall between the 2 room to circulate air

Do I need:
a dehumidifier
a combination of fans to circulate the air
to exhaust bad air to the outside / bring fresh air inside

Here are some facts:
Total SF = 682

Asked By D Moye | Sep 30 16

34 Answers

Choosing a wall assembly: discussion

I really tried to not ask this question since I'm aware that it has been discussed a ton, and I have read a ton on the subject. And even if I've accepted the fact that there's no clear answer, I still have to choose a wall assembly - double wall, 2x6+4"foam, SIP, or some hybrid. Around R40 (I have 12" to work with)

The top priority here is actually budget and ease of construction/quality control.

I've gone through many articles from BSC and GBA amongst many other case studies. This is how my thought process went:

Asked By Bernard Lam | Sep 27 16

2 Answers

Heat pumps and traditional heating

We are about to install a Fujitsu minisplit heat pump for our cooling and heating needs in our 100 year old 2000 sq foot row-home in Montreal Canada, (zone 8 million). We currently have electric hot water radiator heating.

I am curious how I manage to keep the two units from "fighting" each other over who gets to heat the house. I know that when the depths of winter arrive, the heat pump alone will not be able to heat our home.

Is it simply a matter of setting the thermostat for our main heating system a degree lower than the minisplit?

Asked By Sean Lewkiw | Sep 30 16

2 Answers

Can I install 3/8" T-1-11 clear siding over existing 5/8" T-1-11 siding to create a board and batten look?

My house is currently sheathed in 5/8" T-1-11 siding. I'd like to add another layer of 3/8" clear (no grooves) T-1-11 siding over that and then add 2" battens to create a board and batten siding look. Is this a good idea or a recipe for disaster? I live in Maui on the dry side of the island and get a lot of sun on the south and west sides of my house.

Thanks and Aloha,
Bruce

Asked By Bruce Lowrey | Sep 29 16

1 Answer

EPS foam for loadbearing applications "Geofoam"

I found a bit of info today that I thought I ought to share. There is actually a standard for EPS used in structural applications (like under a footer). The standard I usually see is ASTM C578, which specs "Type I", "Type II", etc. There's a second standard, ASTM D6817, which gives a requirement for compressive resistance at 1% deformation, the maximum safe pressure for long term loads.

I found one manufacturer's nice little cross reference between the standards at http://www.styrotech.com/downloads/EPS-DataSheet-ASTM-D6817.pdf

Asked By John Ranson | Sep 30 16

5 Answers

Masonry on concrete columns - air gap or not?

New construction in zone 7/8.

We have several free standing concrete columns that support deck framing and porch roof framing which will have a full thickness traditional stone veneer installed on them. Should the stone on these columns be installed with brick ties, weep holes, and a 1" +/- air gap, or grouted solid to the concrete?

We also have two concrete retaining walls that will receive the same stone veneer on the exposed side, the side of these walls that contacts the soil will be either damp proofed or water proofed, same question as above, air gap or grouted solid?

Asked By Chris Armstrong | Sep 12 16

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