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1 Answer

what is mini split short cycling? turndown?

I understand that a "somewhat" oversized mini split will generally run at a more efficient rate, as opposed to an undersized mini split, which will run full-out, and therefore be less efficient. It sounds as if the problems with oversized mini splits would be 1) wasted money on oversize equipment, and 2) decreased dehumidification, due to the equipment not running enough. Am I about right, so far?

Asked By Ben Rush | Jun 25 17
7 Answers

Looking for a cost-effective, “traditionally styled” double-hung window with U-factor of about 0.20

I am building a new house in Hopkinton, NH. (on the border of climate zone 5A & 6A) and am looking for a double hung window with a u-factor of .20 (or better of course) that will look good in a New England farm house styled home. What I mean by this is I would like a clad exterior with a wood interior and SDL grills without having to spend $65,000 on a triple glazed loewen or marvin window. Don't get me wrong I have used both brands of window on customers houses and they are beautiful, but they are not in the budget for my own house.

Asked By Eric Marchand | Jun 22 17
6 Answers

Halogen-free electrical cable

Does anyone have experience using halogen free electrical cable in residential buildings? I'm going to have to do some rewiring in the house, and I'd prefer to keep it low halogen (for less toxicity if it burns and because I'm not a fan of PVC). I know that LSZH is used extensively in industry for certain applications, but I can't find much information on it for use in homes.

Asked By Kathryn Oseen-Senda | Jun 23 17
7 Answers

Which ductless minisplit?

Zone 4 climate - 735 sqft - R25 walls - R40 roof - R5 windows - very tight ICF home - glazing is minimal with a low SHGC

A Manual J was done and it showed a 1 ton unit would heat/cool the home. I'm undecided if I should bump up to a 1.5 ton unit? Here are my options:

A - DuctlessAire Mini-Split - 1.5 ton - 21.0 SEER - $1,400
B - DuctlessAire Mini-Split - 1 ton - 21.5 SEER $1,060

Is it worth the extra $340 to up-size to the 1.5 ton unit?

Asked By Peter L | Jun 22 17
0 Answers

Dense Packing Flat Roof

Hi Recently I've been wanted to upgrade my insulation as my house was built in 1975 and I'm sure the insulation is not pulling its weight.. I got an estimate from an insulation installer who said that they can take of the fascia board vent screens and put in and blow in cellulose and pack it in in the flat part of the roof. I asked him about moisture and vapor issue and he said that it wouldn't be an issue. Although I am a bit hesitant on this as I'm sure it will be an issue down the road. I was wondering if some of the experts can lead more info on this situation.

Asked By Beach13 | Jun 25 17
0 Answers

Insulating Exposed Cement Wall

Zone 4 NC build, on a steep slope which requires some foundation trickery. One spot I have a question about is the exposed portion of cement wall that is between lower level living space and the air space beneath the garage(garage is on steel beams). See the attached pics. The plan was to do 2" foam board around the entire lower level cement foundation areas(inside). Will that be enough in this spot when you account for the 2x4 wall + the additional insulation inside that wall or should I do thicker foam along that wall since it will forever be exposed to air?

Asked By Kevin Spellman | Jun 25 17
0 Answers

asphalt-compatible waterproofing material

I'm looking to waterproof the exterior of our foundation (along with drainage board, footing drain, etc.)

I was looking at Masterseal HLM 5000. However, we have a bit of damp-proofing that was applied -- some type of asphalt emulsion that was slathered just between the footing and wall joint.

I contacted BASF to see if we could just leave the asphalt emulsion in place and apply the HLM 5000 over it, and they said no... that it would need to be removed.

Asked By Maurice A | Jun 25 17
3 Answers

Air barrier between garage ceiling and living space above

I'm planning to build a "pretty-good" house in climate zone 5b, just south of Denver. My house has an unheated but well-insulated garage below a Great Room above and I am trying to figure out the air barrier. Floor design is, from top to bottom:

1) Laminate floor finish
2) OSB floor sheathing
3) 11 7/8" TJI w/ cellulose insulation
4) 1" EPS for thermal bridging,
5) 1/2" drywall installed using airtight drywall technique.

Asked By Lawrence Martin | Jun 24 17
0 Answers

Concrete Slab Reinforcements : M100 vs F100 fibers : finish and strength

My concrete contractor has 2 fiber choices for the slab pours : M100 and F100 from BASF. Both are polypropylene fibers, the difference is the size.

Officially M100 is only to be used to prevent shrinkage cracking. Unofficially it has been used (with apparent success) to replace light wire mesh in slabs poured in Southern Ontario. Concrete contractors prefer it when a smooth finish is requested as the extra fine fibers make the slab easier to finish.

F100 is a larger fiber, that is approved by BASF to replace light gauge wire mesh. There is no question this is the robust choice.

Asked By Mai Tai | Jun 25 17
15 Answers

Frost wall foundation details for stone and siding construction

I am planning a slab on grade build (24"X8" footings, 4' deep, with 4'6" frost walls). I am having issues with the location of all the sub components on the frost wall width, specifically on the stone detail wall (front wall only).

Asked By Mai Tai | Jun 18 17
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