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12 Answers

Engineer ambushes salesman, or "what do we do about HVAC?"

So at this point, I have done a Manual J load calc for my house that puts the heat load at around 20,000 BTUs. I know that I want an electric heat pump so I can eventually go net zero. I *think* that I want it to be the Bryant Evolution 280a, which has the highest HSPF (13) that I've been able to find in a ducted heat pump. Seems simple enough, right? "Quote me an installation for this unit."

But so far I have been unsuccessful in getting any HVAC companies to bid. Not one. Four salesmen have come by, and no bids. Zero.

In Mechanicals | Asked By Nate G | Feb 7 17
3 Answers

Insulating around heating ducts running between floor joists

I'm in the process of renovating an older bungalow home in climate zone 7a. It currently has an unfinished basement but I am in the beginning process of retrofitting this. It is a heated basement and plan to finish it into a living space.

I've been taping the seams and joints of all ductwork with foil tape and then planning to insulate the ducts. ALL of the heating ducts run under the main floor between the floor joists.

In Energy efficiency and durability | Asked By user-6759891 | Feb 10 17
2 Answers

Second story hydronic radiant floor system

We notice that the hydronic system for the 2nd story tends to warm the ceiling of the 1st floor rooms below rather than the floors as was intended. Our second story was built with hydronic loops between the floor trusses on the underside of the subfloor using thin metal (not aluminum) heat transfer plates. Laminate flooring and some tile in the bathroom cover the floors. I read and others suggested to blow insulation between the floors and insulate the ceiling cavity to force the heat upwards.

In GBA Pro help | Asked By Greg J | Feb 10 17
6 Answers

Complete basement retrofit for 1974 home in Climate Zone 7a

Hi, I purchased a 1974 bungalow in Alberta, Canada, so climate zone 7a. Some specific info on the home:

  • Basement unfinished... foundation would be like this http://bit.ly/2kadR6I, and may or may not have a bitumen layer around foundation. There is definitely no exterior insulation, poly under the slab, foundation drainage, or sump pump. The foundation rises approx 2’ above ground-level.
  • In General questions | Asked By user-6759891 | Feb 9 17
    3 Answers

    Curious what the best way is to retrofit (air/vapor seal) my home to make it more durable & energy efficient

    I have a ranch style home with a walk-out basement on a poured concrete foundation. It is framed with 2x4 walls, fiberglass batt insulation, OSB exterior sheathing, standard housewrap, floor/roof trusses, tar paper on roof and shingles. The basement is finished. It's a pretty standard house. I want to get the most bang for my buck without tearing down and rebuilding. I am in Virginia, climate zone 4. What would be the best way to go about doing this?

    In General questions | Asked By Spencer Shemwell | Feb 10 17
    4 Answers

    When to try and when to fly

    I live in 1300 sq ft 2 story home built in 1908 in NW PA. We did some renovation in 2008 but mainly focused on inside finish and trim. I'm very focused on energy efficiency and green living. My thought was to go forward and apply know green renovation techniques to this house ( insulation, air sealing, better mechanicals, etc.) However, I'm afraid that this work is pushing beyond what this home's value is. I really believe in what Martin said about the greenest homes are the ones that already exists.

    In General questions | Asked By Armando Reyes | Feb 10 17
    2 Answers

    Insulating Basement/Crawlspace... among other things

    My house was built in the late 1800's and is in climate zone 4C in Oregon. It has about a total footprint of 660 sq ft and is half basement/half crawlspace with a cripple wall all along the perimeter. Both basement and crawlspace are unconditioned with no venting. The grade slopes toward the house from the backyard. I'd say in the backyard the grade is half way up the 19" high cripple wall and in the front yard grade is 8" below the top of the concrete foundation.

    In Energy efficiency and durability | Asked By CurryRojo | Feb 9 17
    2 Answers

    Salvaged ash lumber? - Emerald ash borer damaged trees

    Last year I promised some pictures of Emerald Ash Borer tree damage; I recently stumbled upon the images I had selected, but never posted.

    Attached are images of the insect damage on a log and standing tree. Also an image of one of the clues that an ash tree is in trouble, marks from pileated woodpeckers hammering away at it.

    Ash doesn't come to mind as a common building product. However, with such significant numbers of ash trees now standing dead, maybe that will change?

    (Probably will be hard to get a decent baseball bat down the road...)

    In Green products and materials | Asked By Andrew Bater | Feb 9 17
    1 Answer

    Metal roof over unvented cathedral ceiling

    Seeking advice on this application.

    Center of home is Unvented Cathedral Ceiling with Closed Cell (possibly flash and batt to reach R value). On top of the sheathing will be asphalt felt, then metal roof. We purchased the Classic Rib from Metal Sales.

    Sides of the home are Vented Attics with fiberglass insulation. Also to have asphalt felt on top of the sheathing, then metal roof.

    I called Metal Sales, and they stated the metal roof can be installed directly to the underlayment.
    Does anyone see any possible condensation issues?

    Climate Zone 5.

    In Energy efficiency and durability | Asked By Bridget Lamberson | Feb 9 17
    5 Answers

    Heat-pump water heater for an all-electric garage apartment?

    We our building a detached garage w/ 2nd story apartment (1 bedroom, ~900 sq ft conditioned space) & debating the system to heat water:
    - Primary purpose for the garage apartment is for our mothers to live in as they age. Mainly for safety reasons, we're not having gas service to the apartment (could do relatively easily - main house has gas service)
    - Cooling-dominated climate (Houston TX)

    In Mechanicals | Asked By Robert Hallenbeck | Feb 8 17
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