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11 Answers

Do magic boxes distribute loads for ductless units?

For my pretty good home I am building( 2150 sq.ft. Zone 5 northern ct. near Sturbridge mass) I have recently got a quote back for mini splits. 5 heads 2 outdoor units Mitzi. Hyper heat. The contractor is at 17k installed. Diamond dealer. He has one head in each bedroom and 2 on the open floor plan. I am curious if there is a way to quantify how much a ducted ventilation system mixes the air around the home? Would a Minotair or cerv balance out the heating and cooling requiring more like 2 or 3 heads?

Asked By Scott Mangold | Mar 20 17
1 Answer

Air handler or fan coil for low load home?

Hello,

I am building a 2,000 sq.ft. townhouse in Oakland, CA. I plan to use a Sanden heat pump hot water heater to provide both domestic hot water and space heating. I am seeking guidance on how best to distribute the heat to the basement, first floor, second floor, and attic loft. Due to budgetary constraints, I am looking for the most economical heating distribution system. While a hydronic distribution system would be nice, I assume forced air is going to be my best bet - let me know if you disagree!

Asked By Gregory Sherman | Mar 22 17
1 Answer

How does ambient temperature affect wetting/drying cycles?

Hello GBA pros & community! I've been a lurker around here for awhile, but this is my first post. I'm enclosing a timber-frame in southeastern Manitoba (climate zone 7A), and plan to build a vented roof assembly with dense-packed cellulose insulation. For reference, the specific assembly I have in mind is as follows, from the inside:

-timber rafters
-1x6 T&G pine ceiling
-ice & water shield (interior air-barrier, class I vapour retarder, and temporary rain protection for the timber-frame)
-18" deep non-structural 'trusses' dense-packed with cellulose

Asked By Benjamin Pries | Mar 22 17
11 Answers

Sound attenuation between floors

I am constructing a floor assembly between a 1st and 2nd floor and may not be able to build up a deep floor assembly due to exposed ceiling timber joists (and the small footprint of my structure). I am considering using 2 courses of Advantec (subfloor) material with perhaps a mass loaded vinyl material in between the subfloor material.

I was wondering if anyone else has constructed a floor assembly that might reduce some of the sound transfer without resorting to a deep floor framed system. Has anyone had success solving this problem?

Asked By John Brown | Mar 15 17
6 Answers

Eco Star windows and patio door

A friend had a sales visit from a contractor that installs Eco Star windows. Some of the R/U values my friend said he was promised sounded questionable to me. On the web I see they are reviewed well but would love a "real" experience from anyone in GBA. Anyone work with these?
Thanks, PK

Asked By Paul Kuenn | Mar 20 17
20 Answers

Do I need to put rigid foam on a crawlspace dirt floor?

I live an old 1890s brace/balloon frame in Virginia (Climate Zone 4). Do I need to put rigid foam on the dirt floor? My contractor is adamant that I need to either insulate the dirt floor or the ceiling above to be compliant with IECC. I was under the impression that I could put a vapor barrier on the floor and insulate the walls with rigid foam. Is there a best practice? And if both are acceptable, how much of a difference does the rigid foam make to the comfort/cost savings? Thanks for any input!

Chris

Asked By Chris Thomas | Mar 21 17
17 Answers

Ultra-Aire XT105H vs. Honeywell DR90A2000

I've seen much praise of the highly efficient (most efficient?) UA XT105H whole-home dehumidifier in my research. It certainly seems like a winner. As with many things, though, having the best often comes at a price and the XT105H seems to be no exception to that rule. See below for the specs:

http://s7d2.scene7.com/is/content/Watscocom/Gemaire/article_142249153705...

Asked By Lance Peters | Mar 1 17
10 Answers

Air King Introducing most efficient fan?

I was mulling around on the Energy Star website and came across a listing for an Air King in-line fan. Curious, I checked out their website and also found they have a new line of DC motor exhaust fans coming to market.

According to a page on the 2017 AHR Expo website, these new Air King D4S and D4D fans will be the most efficient exhaust fans on the market:

http://ahr17.mapyourshow.com/7_0/exhibitor/exhibitor-details.cfm?ExhID=1...

Asked By Lance Peters | Mar 21 17
5 Answers

References for best practices for green building?

What best practices manuals for would people recommend incorporating by reference into a building spec? Rather than reinventing the wheel, where possible I would like to refer to existing documents.

For example, I don't think I can put together something half as good as The Hammer and Hand Best Practices Manual for rainscreen details.

--John

For reference, I'm building a slab-on-grade with double walls and a trussed roof in zone 5 near Rochester, NY.

Asked By John Ranson | Mar 21 17
6 Answers

Question about wiring minisplits — electrician's mistake

I consulted with the electrician before he ran the wiring for our new home. I knew that mini splits weren't something they would see everyday, so I wanted to make sure everyone was on the same page. We noted that the unit needed three wires plus the ground, and everyone knew what that meant because I had to run to Lowes to pick up some extra 12/3 wire since they were running low.

Asked By Clay Whitenack | Mar 21 17
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