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0 Answers

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
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
6 Answers

Considering ERV pre-heating options (maybe cooling too)

Hello from a long-time lurker but first-time poster!

It's hard to express how helpful and inspiring this website is to a non-professional like myself. I'm particularly taken by the generosity of spirit shown by all who contribute thoughts, ideas, and experience with such passion. It seems that everyone wants to do their part to help heal our hurting planet--buildings are a huge part. Thank you, thank you.

Okay...end of speech. Some details about our build plans.

Asked By Richard Hoenich | Jun 24 17
28 Answers

Exterior foam and fires

There has been a fire that gutted a high rise apartment building in London. It appears to have spread through the foam-filled exterior cladding panels. Similar fires have occurred in tall buildings in Dubai.

While the situations aren't directly analogous, I wonder if there are any lesson here for builders contemplating the use of exterior foam?

https://www.theguardian.com/uk-news/2017/jun/14/disaster-waiting-to-happ...

Asked By Malcolm Taylor | Jun 14 17
4 Answers

How much of a gap should I allow in exterior plywood sheathing to allow for expansion and contraction?

Thank you to everyone who has posted and responded to related questions and gotten me to the point where I can more or less ask this question in an intelligible manner.

Asked By Joel Fyke | Jun 24 17
10 Answers

How does someone cancel subscription when there seems to be no way out??

Could someone guide me in the cancellation of membership? it doesn't seem like it is possible to do so.

Thank you

Asked By James Someone | May 27 17
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