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2 Answers

Hot water recirculation loop with PEX homerun system?

Has anyone played with the idea of doing a hot water recirculation loop with a pex manifold homerun system?

My desire for a recirc loop is mostly inspired by Gary Klein and my reading/watching of his work. Although he doesn't recommend a home run system because you can't recirculate hot water.... well, I think it might be possible. Maybe I'll sound crazy here, but what can I say, I love systems design.

I see this as 2 issues:

1. Is it doable?

In Green building techniques | Asked By Jamie B | Feb 17 18
1 Answer

ERV vs fresh air intake

So my HVAC design is looking like I will do a fancoil on each floor.

I'm seriously considering going with an air-to-water chiller for the outdoor unit and a spacepak aircell on each floor, 4 in total.

These units have a 4" round fresh air port that you can program a percentage of fresh air.

In Energy efficiency and durability | Asked By Jamie B | Feb 17 18
8 Answers

One Multi- or Two Single Mitsubishi heat pump outdoor units


In Mechanicals | Asked By david flinn | Feb 14 18
3 Answers

Any recommendations for financing an off-grid house in Canada?

I have my heart set on an off-grid house in Ontario, Canada. I thought it would be a relatively easy purchase but every mortgage broker that has looked into it has come back saying that the bank will not finance an off grid house. I don't know if it's worth it to try again but that means multiple credit checks which is not the best either.

Can anyone recommend anyone in Canada that could help? Time is of the essence! Any advice extremely appreciated!

In General questions | Asked By Laura Mandy | Feb 16 18
5 Answers

Are 48" Baseboard Diffusers necessary?

Doing flooring and have pulled out the baseboard diffusers from 1959 house. They are 48" long but the hole in the floor is only 2" x 12". Can I replace with a smaller size or is the 48" length helping to spread the warm air around the room? Note that there are 2 of the 48" diffusers along the same wall in the 14' x 17.5' living room.

Thanks in advance!

In Energy efficiency and durability | Asked By MollyV | Feb 12 18
6 Answers

How do I support interior attached garage floating wall ?

My split level late 50’s home in southern NY has an attached garage. The wall separating the garage is a floating wall and the garage level is on a cement slab, with a block and framed wall. The joists in the ceiling parallel this wall and there are no joists sitting on the wall for support- the wall is between 2 joists letting lots of cold air into my home.

In General questions | Asked By JakeNY | Feb 13 18
9 Answers

BEopt: Too good to be true?

Has anyone used BEopt software? Are the results reliable?

I entered my design into BEopt. I had to create many of my own options. For instance, there was no description for my R22 exterior foam. I think I understand the process and how to use it.

My Assumptions:
Detroit, Michigan (CZ5)
1040 sq. ft.
71° heating set point
76° cooling set point
11 ft. walls. (There is no option for my shed roof design so I averaged.)
R40 walls (Nominal R22 external EPS and R21 batts downgraded for framing)
R80 vented roof (24" cellulose in ≥ 30" parallel chord trusses.)

In General questions | Asked By Thrifttrust | Feb 13 18
4 Answers

Ventilation ducting advice

It looks pretty likely I'll be running my own ducting, as I have been left with a supply of specialized duct pipe and distribution accessories after my main builder turned into a ghost. I understand the basics, but some of the details I'm not sure about. I have 13 distribution boots, and it's pretty clear the intent was to have 3-4 exhausts, and 9-10 supplies. Two bathrooms and the kitchen obviously need exhausts. He actually installed half of the boots, and I notice he put two in the large living area, at opposite ends. Should one of those be an exhaust, or should they both be supplies?

In Mechanicals | Asked By Trevor Lambert | Feb 16 18
18 Answers

ERV recommendations

Hi, I need to make a fairly quick decision on an ERV. The house build is many months behind schedule, and the builder has fallen off the map so it looks like this part of the project I may have to contract out to someone else. Before the builder disappeared, we were in line to get a Jablotron Futura (formerly Air Pahoda). They really pushed this brand, and I'm embarrassed to say I didn't do any research in ERVs, so I don't even know for sure it's any good (we were told by them it's the best, the reasons for which I didn't delve into, again to my discredit).

In Mechanicals | Asked By Trevor Lambert | Feb 13 18
8 Answers

Are ductless minisplits a viable solution for a 200-year-old timber frame retrofit?

Project type: full house renovation; currently down to the stud.
House type: 200 year old timber frame style farmhouse
Location: Milton, NY, USA

We're in the midst of a full-house renovation of a building that sat vacant for 20 years. We replaced the roof and applied closed-cell spray foam in the attic and gable wall extensions. The intention is to closed-cell insulate the remained of the building envelop upon completion of MEPs.

In Mechanicals | Asked By User-6952768 | Feb 13 18
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