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4 Answers

Plastic or smart vapor barrier in zone 6?

My builder is planning on using a normal 6 mil vapor barrier on my new build ...the wall structure is R-22 fiberglass with 5 inches of EPS foam on the outside ....the building inspector says that is code ...

Asked By bob holodinsky | Oct 18 14
2 Answers

Rated output for electric radiant ceilings?

I've been searching the web for a rule of thumb to calculate the rated output for a 40 year old electric radiant ceiling system. Must be some rule of thumb like 10 btu per suare foot......but I can't find it.
Thanks

Asked By Walter Gayeski | Oct 17 14
2 Answers

Catherdral ceiling insulation

We have a cape cod and are having a new roof installed. The stairs leading up to the second story, the cathedral part, with two rafter bays of 2x6's had no insulation in them. The roofers pulled the roofing deck and put in some batt insulation, (R30 with a plastic wrapping that had holes) and some attic cat they put in by hand. They also put in plastic baffles between the decking and the insulation. Unfortunately at the bottom of the rafters it is completely blocked off. So there will be no air being pulled in from the soffets. There isn't a way to get them open.

Asked By HD S | Oct 16 14
2 Answers

Best integrated system for water heating and radiant floor heating?

I'm looking to remodel my home and install radiant floor heating system. Can anyone provide any information on good heat sources (boiler, water heater, etc) and system arrangement (direct, indirect, closed loop, etc). Is it okay to combine DHW with radiant heat or is there some over arching reason why they should be kept separately?

Home details: Just south of San Francisco, 2500 sqft, two stores, 5 zones, Warmboard S floor board, mostly covered with hardwood flooring.

Asked By Dmitriy Khazansky | Oct 17 14
10 Answers

Radon

Question for you:
My basement was tested at 5.1 and then 6.5, short term tests. unoccupied space.
The living room first floor was at 2.7.

If still interested in radon mitigation, how can this be done at the slab if this is an 80yr old home that does not have any stone under the slab in the basement? The floor is on soil?

Thanks,

Dave

Asked By Dave Mac | Oct 13 14
3 Answers

Experience with Rinnai vent-free convectors?

Anyone used or have experience with Rinnai Vent-Free Convectors?

I'm a little baffled by this product. No ducts, no vents, nearly 100% efficiency. Relatively low cost, relatively low total load. Am I missing something here? It seems like the low load crowd would be all over these, as a backup heating up for high efficiency minis if not as a main line unit.

http://www.rinnai.us/vent-free/products

Asked By Keith H | Oct 16 14
6 Answers

Which point-of-use tankless water heater should I get?

I live in Cambridge Massachusetts. I need a point-of-use tankless water heater for 1 bathroom sink. I will use the hot water for about 5 minutes at a time. What is the correct size? Can you recommend a brand?

Asked By Eve Schlapik | Jun 9 14
6 Answers

"Venstar Free Cooling"

I saw this in the instructions for a Venstar Thermostat, which is a fresh air intake to provide "free cooling" when the outside temp drops. The main return would close and the fresh air open with only the blower running.

I suppose that the fresh air intake should be the same size as my normal return (18") for the outside air to do anything right?

the drawing also shows a barometric damper at the return grille for pressure equalization.

Would this save me money in Sacramento CA? What are your thoughts...

Thanks!

Asked By Manny Manuel | Oct 15 14
1 Answer

Vented roof insulation

For a vacation home in a 5b zone, does it make sense to put exterior rigid insulation (1" xps) under a standing seam metal roof? This will have a vented attic with no mechanicals up there. I anticipate blow-in on the ceiling deck.

Asked By Robert Holland | Oct 16 14
13 Answers

Replacing a natural gas gravity furnace in an upgraded small older home

I am a regular reader here and have learned a lot on this site. Thanks to all who contribute.

I have been upgrading the thermal envelope in a 960 square foot house in Detroit, Michigan for several years. I have injected polyurethane foam in the walls, R60 cellulose in the attic after air sealing, 2" XPS on the basement walls, and 2" XPS in the joist cavities in the basement. The windows are single pane but with caulked in place storm windows.

Asked By Gregory Worrel | Jun 1 14
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