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3 Answers

What radon mitigation system do I need?

Master bedroom replaced a concrete slab garage area that was built in 1953. We were curious about radon and had it tested in this area and lab results were 18!! This was the lowest part of our house. Rest of house has a crawl space and is elevated about 3-4 feet from Master Bedroom. We had the rest of the house tested for radon and it was a 5. We are not sure if the slab for the previous garage had a vapor barrier or not. What do we do?

Asked By Jimmie-lou | Feb 21 18
3 Answers

Dehumidification and (or vs.) mini-splits

I'm in Austin TX. We have significant humidity, including in "shoulder" seasons where cooling is not really needed but dehumidification is. Probably the worst times are when the day is hot and humid, but the night is cold, condensation on windows is a major problem all over the city. No one likes running the AC to super chill just to dehumidify.

So the smart recommendation is a dedicated dehumidifier, like the Ultra-Aire series. Ok, costs a bit more than AC only but everyone says they are great.

Asked By James Howison | Feb 22 18
1 Answer

Midea Ductless Units

In our full-house renovation, we have decided to replace the oil furnace with a series of mini splits throughout the house. We have met with multiple HVAC contractors to price the project, and were/are planning on going with the Mitsubishi product, until recently when one HVAC installer (who also installs Mitsubishi) recommended Midea. This was the first time I've heard of this brand and a cursory search on the internet doesn't show a significant US market share.

Asked By Ryan Wiley | Feb 22 18
7 Answers

Advice on trimming out exterior light fixture where pancake box sticks out too far?

Hi guys,

I have a few exterior light fixtures I need to install but the existing pancake boxes are sticking out over an 1" from the siding.

I attached a few photos I found online that are identical to my situation.

The pancake box is installed in the wall so it cannot be removed.

What would you guys recommend I do here? Are there are deep trim boxes I can mount over the pancake box to water seal it? And then install the light fixture?

Or do I need to custom make one out of a wood block?

Any ideas you guys have would be great.

Asked By MichaelBa | Feb 18 18
3 Answers

Is PERSIST really practical in coastal Maine?

Hello, all! We are in the planning stages for building a ~1300sft home in coastal Maine (6A, I believe), and are trying to strike a balance between performance, low-maintenance and cost. We've found Persist to be an elegant solution, and we really like the look of having the exposed framing on the interior - Matt Risinger's work in Austin comes to mind.

For us to reach the desired R values of the walls, there seems to be good details and best practices out there for fastening thick amounts of foam.

Asked By user-7005034 | Feb 21 18
2 Answers

Decentralized ductless ventilation system: Zehnder, TwinFresh, or Lunos?


Background...We are building a 2000 sq ft home at 7000 ft in Colorado, climate zone 6b, with about 7000 HDD. The house will be tight but we are NOT going for any certification. It is one story, 3 bed, 2.5 bath. My spouse has lots of allergies and is opposed to duct work. As we live with doors and windows open a fair amount of the year he is opposed to adding ductwork in the house for an HRV OR ERV. Whether that makes sense is NOT the question.

Asked By User-6990904 | Feb 21 18
1 Answer

If UL-approved aluminum tape is applied to the return side (bottom) of air handler to filter base, is mastic still required?

A co worker and i disagree on this mastic is required where condensation will allow tape to peel. But condensation does not occur between the filter base and air handler on an upflow system. Correct?

Asked By Acrescue Tech | Feb 21 18
11 Answers

Lessons learned from exterior basement insulation retrofit

I've attached a link to photos and comments that I created to share my recent (last week) experience with an impromptu opportunity to add exterior insulation to a portion of my basement. Lots of things I could have done better here, but in the end I'm glad I spoke up and asked to make the house better.

Asked By Mike McLaine | Feb 3 18
5 Answers

Slab on Grade in Climate Zone 6

Hey all,

So watching a bunch of Matt Risinger, he's always talking about slab on grade builds, and how we have basements in the far north etc. I know these topics have been brought up before.

I'm in Climate zone 6, Toronto. I'm designing a 100sqft satellite building, or you could call it a shed with all the bells and whistles of plumbing, elec, heating etc.

I'd like to do a frost protected slab on grade for this to incorporate infloor radiant hydronic heating. The slab will essentially act as the radiator, and be the base for the Insulated perimeter wood stud walls.

Asked By Jamie B | Feb 17 18
9 Answers

Innie/outie window operation

I am familiar with much of the conversation regarding thermal performance as it relates to innie/outie windows (http://www.greenbuildingadvisor.com/blogs/dept/musings/innie-windows-or-...). My concern here relates more specifically to operation of innie/outie windows as well as "middies".

My concern is as follows:

It seems that "conventional" windows on regular houses are either double-hungs, sliders, single hungs, casements, or awnings, all of which swing outward or slide in one plane.

Asked By Ethan T | Feb 20 18
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