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8 Answers

How important is a thermal break between a house foundation and an attached garage foundation?

Our footings were poured today for a new house and attached garage. The walls of the basement foundation (9') and garage foundation are scheduled to be poured next week.

Looking over the plans, our concrete sub is worried about the 7" thermal break between the basement and garage foundations (no physical connection) as currently drawn on the plans. The separation is there in order to allow us to attach 5" of Roxul Comfortboard 80 to the basement foundation (we'll be doing the same for the whole exterior perimeter of the basement foundation).

Asked By Eric Whetzel | Dec 2 16
2 Answers

What is the relationship between air source heat pump and indoor heat pump water heater?

I am sure this has been analyzed here before, but I want to check my reasoning. A criticism of heat pump water heaters is that they cannibalize the home heat source and so during the heating season perform exactly as electric water heater efficiency. However if the heat is provided at COP 3 from an external air source mini split, then am I correct that the heat that is being "borrowed" by the heat pump water heater is also COP 3 and so year round the heat pump water heater functions at COP 3 or better?

Asked By ven sonata | Dec 5 16
1 Answer

Filling nail holes in Zip?

I have a question. Framing almost done. Have exterior sheathing done with Zip board.

I noticed that the framers' guns' pressure was high, and nails in some areas went deep into Zip, or in some areas nails missed the studs.

Question: Does it make sense to try to fill deep shot nails with a liquid barrier of some type?

If yes, what type?

I was also thinking of putting a stapled or peel-and-stick weather barrier over the Zip instead. Does that make any sense?

Asked By Boris Rubinstein | Dec 5 16
0 Answers

Mini Split Questions

-I'm in zone 4, midwest US, and am about to buy a ductless split system for my main structure and the addition I'm finishing now. I am concerned as three of the five rooms I am putting them in are pretty oversized (~2600k btu load cooling, using the 6k heads) and the rep is saying I should go with the H2i. He said if I never need the low temp operations, the heater was worth the money.

Asked By Mike M | Dec 5 16
3 Answers

Fill stud cavity with fiberglass insulation?

I am finalizing a house design in zone 5. Exterior walls to be insulated with R10 XPS exterior of the sheathing and R13 fiberglass in the wood stud cavity. Peel and stick will be directly applied to sheathing per REMOTE style walls.

My concern: wood studs will be both 2x4 and 2x6 construction, with 2x6s where walls are tall (10 ft.). Is R13 insulation pushed towards exterior (I'll have to figure out the best way to do that) OK or should I fill the cavity with insulation in the tall walls? Will ratio of R19 to R10 work re: moisture control?

Thanks in advance.

Asked By Joel Cheely | Dec 4 16
9 Answers

How to employ a mixing valve in a closed loop radiant heat system

We are just wrapping up the new roof on my project house and now its [past] time to turn our attention to HVAC - or, more specifically this time of year, Heating! This 1975 house came with radiant heat ceilings as the only source of heat. Recently we have been having night time lows in the teens and daytime highs here in Northern Nevada zone 5 at 5000 feet are usually in the 40's. I have done some preliminary calcs on heat gain/loss, and plan on doing a full Manual J model before laying out any cash for components.

Asked By Roger Smith | Dec 1 16
1 Answer

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall. Will that be an adequate drainage plane? Or are furring strips also needed?

Asked By Courtney McCracken | Dec 5 16
3 Answers

How would you air seal existing sheet rock to the bottom plate?

Building a new house in Syracuse NY. Sheetrock is up but no trim, mud or paint yet. I have been doing a variety of things to air seal and am looking for advice on how to seal the sheetrock to the bottom plate. The bottom plate is already sealed to the subfloor. Foam, caulk or tape? I have used foam in a previous house but I am not sure that it worked very well. I am leaning towards tape. Any suggestions?

Asked By david schreiber | Dec 3 16
7 Answers

Ipe wood vs. Azek (PVC) decking

My cedar deck has rotted. Periodic sanding & staining extended its life but now it is over. I am considering using either ipe wood or a PVC decking material (brand Azek). From the little I know, trying to consider a life-cycle assessment, neither seems like a great environmental alternative. Is there a clear choice between the 2?

Asked By Betsy Leibson | Apr 11 16
8 Answers

Boards covering the top plate to air seal in attic - Top plate is not accessible

Many of my top plates are completely covered by other boards. I.e. Some of the top plates have 2 2x4 boards butted together on top of it (Effectively making a 2x8 with a split in the middle.) While this 'covers' the gaps I do not believe it creates an air seal.

Should I assume it will be sufficient to seal around and between these boards?

- It would increase the length of my sealing by ~ 50% since I would be doing two sides and a middle. (Not counting the ends which are negligible). However would be much easier than prying them up.

Asked By Charles Lee | Dec 1 16
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