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5 Answers

Rigid polyiso in side attics?

As a spray foam alternative, I'm considering using continuous rigid foam along the 32ft long x 7ft slope in my side attic and just spray foaming in the lower joist bays and places where taping is difficult. The attics are about as simple as can be with no dormers or other obstructions. I will need 8" of polyiso to meet my disired R-value (R-48), while keeping the 2x4 rafter bays wide open for ventilation. There are also HVAC ducts and plumbing in the attic, which is why I'd like to convert it conditioned space.

Asked By Ryan Griffin | Nov 22 14
6 Answers

Designing a passive solar / net zero house in NC Mountains

My wife and I are designing a new mountain home in Banner Elk, NC. We are in the initial design stages with our architect and are confused by the numerous options to consider. Our house will be built in the Eagles Nest community which has a pacific northwest lodge feel. Our home site is at a 5,000 foot elevation on the mountain ridge with a northern view.

Asked By bill Moseley | Nov 23 14
0 Answers

Could you please provide me of an example of a one temporary one floor sustainable building?

I am currently undergoing a project at college and i need to research temporary sustainable buildings

Asked By Alfie Andrews | Nov 24 14
2 Answers

Heat-pump water heater in conditioned space

I am building a net-zero energy home to Passive House standards in the Seattle area. The best scenario for a heat pump water heater is in an attached garage, unheated basement or in the conditioned space of a house in a humid heating climate (why doesn't everyone in Florida own one?). Unfortunately, my only option is within my conditioned space in a heating climate. My heating system will be a ductless minisplit air source heat pump. I would prefer to not remove the heat from my utility room only to make my heating system work harder.

Asked By Gerald Blycker | Nov 24 14
4 Answers

Mid Roof Edge Vents / Ice Dams

I'm located in Michigan and in the process of putting on a new roof and want to address some issues relative to poor ventilation and ice dams. Overall, the attic is well insulated, but because of the roof design the hip roof in the center has almost no air intake. My plan was to address this using mid roof edge vents.

Asked By Robert Eaton | Nov 23 14
12 Answers

Does radiant heat recycle water

With regular radiant heating systems that use warm/hot water to run through tubes in the floor to heat the home, what happens to this water - does it get recycled through the system, heated up again, or does it go down a drain?

Asked By Celina Jones | Nov 22 14
5 Answers

Help with Green Addition and hyrdonic heat demo

I am in the process of designing a pretty substantial addition onto my home in central Missouri. I understand that our relatively low electricity costs will not be around in the next 5-10 years in the US and am planning for this.

Asked By Michael McArdle | Nov 23 14
13 Answers

Options for garage heat

I would like opinions regarding options for heating a garage. I know, I know, "Why the H@!! are you heating a garage?" will come to mind for many of you. Others will agree that it saves on car repair costs, improves longevity, and allows for storage of "perishables" such as paint cans, bulk canned garden vegetables, and other things wife understandably does not want in house.

Here are the pertinent factors shaping the decision:
* Super-insulated house, Manual J heat load calc gives 12,400 BTU/h (3.6 kW) peak heating requirement (for garage alone)

Asked By Kent Jeffery | Nov 20 14
3 Answers

Can rigid foam insulation have an air space between it and rim joist?

I am insulating my rim joists with 2" rigid foam board. Most of the rim joist is bare, and the foam fits along it nicely. Some sill boxes have some small irregularities (vent pipes, plumbing, etc) that I have worked around easily enough.

Asked By Susie Derkins | Nov 22 14
19 Answers

Polyiso on interior

Martin/Dana

Living in the Bellingham area north of Seattle it can get cold. The house was heated by propane, it was a cost that was hard to get hold of especially with some of the design of the house. (high ceiling)

I set out to improve the insulation of the home taking bits and pieces off the internet as to the techniques available these days.

I am a bit "OCD" now that the living room is for the most part done "I have some hidden inward worries". I wonder if I am trapping moisture inside my walls having used the foilfaced polyiso just behind the sheetrock.

Asked By William Lucrisia | Nov 21 14
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