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1 Answer

Ductless heat pumps and conditioned crawl space

Any suggestions for using the two together? I'm intrigued by the efficiency of the DHP's, but don't know how I can get some of the conditioned air into the crawl space without auxiliary fans or such. Thank you for your help.
Philip

In Mechanicals | Asked By Philip Joyal | Oct 5 15
10 Answers

Value of Phase Change materials

Our passive solar house was completed in June of this year. I designed it using principles learned on this web site and Fine Home Building magazine. I followed somewhat the Pretty Good rules found on this site and a great deal of input from the Energy Nerd blog.

Location is Bellingham, Wa north of Seattle right on the Canadian border.
10-20-40-60 insulation.
Triple glazed windows with a good solar gain. Approx 8% window to floor ratio.
Overhangs to provide appropriate shading. South facing.
Double wall, advanced framing. ACH 1.0.
HRV and a mini-split.

In Green products and materials | Asked By Stephen Carlton | Oct 4 15
1 Answer

Sourcing Foamglas

I'm considering Foamglas as footing insulation. Does anyone have contact information for pricing and ordering Foamglas T4+ boards in the US? I've started working my way through the contact info on their website, but I'm hoping someone may already have found the right person to talk to.

Thanks,

John

In Green products and materials | Asked By John | Oct 4 15
10 Answers

How to release stored heat in floor's thermal mass

Years in the planning, five months in building, we are now home at last in our 1,100 sq passive home at 46 degrees North in North Central Minnesota.

Fujitsu Halcyon mini split heating and cooling.Heat load is around 26K BTU

Q 1. Am I correct assuming that I have to set the the two mini splits' thermostats at a night time temp that is lower than indoor temp before the concerete floor's thermal mass will release its heat?

Last night I set mini splits at 66 degrees -- guessing that that setting would be cooler than floor.

In Mechanicals | Asked By Randy Bunney | Oct 2 15
6 Answers

Outdoor reset vs setback on single-stage boiler

I'm trying to figure out what would be the more efficient thing to do in my situation. I've recently heavily insulated the house and installed a radiant hydronic system (making sure to do a detailed load analysis and system design by the Sigenthauler hyrdonic book). While the radiant system and boiler loop are new, the boiler is a 20 year old cast-iron boiler that I want to nurse along for a few more years (mostly because of current budget).

In Mechanicals | Asked By Eric Stormfield | Oct 3 15
2 Answers

Radiant heat and spray foam insulation

I have just installed radiant heat under my deck that is now part of our living space. The area is 24 ft by 6 ft by 6 in and 2 ft of the ground. The pex tubing is attached directly to the deck with alum. heat
transfer plates with a 6 in space from the outside edges. My question is: can I spray foam over the
pex and plates without any airspace at all ?

Thank you

In Energy efficiency and durability | Asked By Anthony Bartolotti | Oct 3 15
13 Answers

Ideal window rough opening gap for good air sealing

The manufacturer I'm ordering windows from allows a rough opening gap around the window of 3/8" to 1/2" from all 4 sides (so the rough opening would be 3/4" to 1" wider & taller than the window).

In General questions | Asked By Nick Hall | Sep 28 15
4 Answers

Odour from Certainteed fiberglass insulation

We just had some Certaineteed fiberglass insulation installed,in our house and have noticed a very strong odour from it. I thought it would dissipate relatively quickly but after 4 days , it is still quite noticeable. In fact, the odour was so strong that we had to go to a hotel because it made my wife sick.

As anyone ever had this experience with Certainteed fiberglass insulation before?
I have worked with other brands of insulation in the past and cannot ever recall that strong of an odour.

Does anyone have experience with Certainteed?
Is this normal for Certainteed?

In General questions | Asked By Aaron Gatzke | Oct 3 15
3 Answers

Insulation for radiant staple up

Hi, we are building a home in climate 5. The house will have geothermal with radiant heat in the basement slab and the first and second floors. We intend to finish the basement at a future date but not right away. Our contractor was planning to staple up the insulation with aluminum transfer plates and insulate with the foil bubble wrap stuff (thick foam under the basement slab.). I have read a lot about insulation for this type of application and it sounds like the foil bubble wrap stuff has little value.

In General questions | Asked By Mel Tillyard | Oct 2 15
6 Answers

Insulating a flat roof in Chicago

I have had continued problems with my flat roof on our 10-year-old 3-unit building. This will be the 3rd time having to do major work.

The ceiling below has about 8 inches of blown in insulation with an 8 inch or so open space above. All of which is within the engineered floor joist that should allow for air flow.

On top of the joists is the main roof deck and on top of the deck is an additional deck that is sloped with the roof membrane on top. The wood is completely rotted out but the main deck appears OK.

In Green building techniques | Asked By Andrew Rothstein | Sep 16 15
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