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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?


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
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!


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:


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:


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.


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
2 Answers

How do I resolve summertime heat issues and winter ice dam issues in a kneewall attic bedroom w/ a blocked /insulated ridgevent?

Hello, I've really enjoyed your site this winter while researching ice dam fixes and then consequently many other building designs and fixes.

I live in northwest Montana in an old house framed with 2x4's in a smaller house with an attic that's been built out. Our house has a valley on the east and on the west side, we have knee walls upstairs. We are going to get our roof redone this summer with snow and ice shield to the ridgetop.

Asked By shmac | Mar 22 17
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