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31 Answers

Heat loads and mini-split.

So had my heat loss calculations done on the new build, and would like some input from people regarding what mini-split they would recommend and placement of the heads, I’m in Zone 6 and the house is single storey with a walk-out basement, total square footage with both floors is 4400.
The following is what they came up with: Main floor Htg load 11889 Btuh, Clg load 12613 Btuh
Walkout Basement Htg load 10792 Btuh, Clg load 2658 Btuh
Total : Heating Load 22681 Btuh
Cooling Load 19582 Btuh

In Mechanicals | Asked By Dave B | Apr 5 18
6 Answers

Patio door: I'm balancing options and need input, please

Good morning from often windy Colorado, 7000 ft zone 6b,

We are building a pretty good house with a north facing patio that has a 9ft expanse for a door. There will be a covered pergola with some sort of clear material above for protection. We are looking at double slider, lift and slide, French with side lites and trifold. The windows will be Alpen.

We are balancing
A. energy awareness, aka air leakage
B. ability to get as wide an opening, aka my husband wants to bring the outside in
C. lost space from the swing needed from French or trifold
D. pricing

In General questions | Asked By Lydia Segal | Apr 14 18
3 Answers

What radiant heat system would work best on concrete floor with tile?

I'm thinking something that would create a thermal break between concrete and tile floor. Anyone with ideas about what to use would be appreciated.. Thanks Rob

In Energy efficiency and durability | Asked By Nuclear Free | Apr 15 18
3 Answers

Overroof venting, aka a weird intersection of roofs...

Hey all, I'm building a home in the foothills of the Cascade mountains in WA. It's listed as Zone 4, but it gets some snow, is on the edge of a rain forest that gives us very wet winters and very dry summers.
The house has two 20' wide roof sections that intersect at a T. One is vaulted and vented using the I-joist method similar to last year's Fine Homebuilding project house. The other roof is a more conventional raised heel truss roof. Ridge vents for both.

In General questions | Asked By Andrius S | Apr 15 18
7 Answers

Dual pane window with 1 tempered pane - should it be inside or outside?

I'm placing the window order for my 'good enough' house and have been through several iterations of colors/wood/Low-e variations, etc. Through 3 iterations, the glazing was always specified as "Tempered Inside Pane only/Fire Glass" but the most recent and (almost) final quote has all windows listed "Tempered is Outside Pane". (The house is in a WUI (woodlands-urban interface) area, hence the 'one tempered pane' requirement). Do I care whether the tempered pane is inside or outside? I searched both this site and the web for recommendations or requirements and came up empty...

In General questions | Asked By Rob Hunter | Apr 15 18
7 Answers

Zone 3 re-siding - exterior insulation options

Hi everyone - my name is Loren. I’ve learned a ton about energy improvements for an older home from this website – thank you for creating such a valuable resource!

I’m seeking guidance and advice on alternatives for adding insulation and improving air/vapor sealing to my home while some walls are being re-sided. Some details:

• 1964 construction, Climate zone 3 (Atlanta), 2 stories (2,330 SF), 600 SF basement w/adjacent
crawlspace. Graded “leaky” in energy assessment done 5 years ago (CFM50 = 5050 N = 17.2
ACH natural .71)

In Plans Review | Asked By Salaryman | Apr 9 18
2 Answers

De-superheating for dhw

I see a product from Olive Tree Energy called a ZeroEnergy Water Heating System. Any experience with these or similar products. Is it a good concept? Maybe one of these added to an indirect tank and electric backup so you can turn the boiler off for the summer.

In Mechanicals | Asked By Jonathan Blaney | Apr 13 18
8 Answers

Basement with back exit door on a landing

In the basement of our bungalow we have experienced seepage in the past. As a result we had the entire exterior of the house waterproofed professionally. The plan it to insulate the interior basement walls this summer using rigid foam against the interior concrete walls, sealing the joints with tape. Additionally, I am planning on a stud wall with roxul batts in between. I have read many of the articles on this site to get to this point.

In General questions | Asked By TylerRR | Apr 14 18
14 Answers

Minisplit sizing dilemma — to replace oil furnace

I love the GBA website. Thanks for so much good information.

We're in the planning phase for replacing the 31 year-old oil furnace in our 1200 sq. ft. house in Portland, Oregon (climate zone 4C) with a mini split heat pump. The heat pumps we're considering is the Daikin FTQ18PVJU or the FTQ24PVJU.

The house was built in 1960 and is 3-bedroom, 1-bathroom, 2-story, slab-on-grade construction. Windows have been replaced with double-pane, low-E windows and modern solid-core wood doors with tight weatherstripping but those are the only energy improvements the house has installed.

In Mechanicals | Asked By Oregon1859 | Feb 25 18
5 Answers

Problems with Blue Light Disrupting Sleep

Recently I watched a show on The Nature of Things called "Lights Out".


In General questions | Asked By Scott Wilson | Apr 12 18
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