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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.

In General questions | 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.

In Mechanicals | Asked By Dmitriy Khazansky | Oct 17 14
15 Answers

Rising power plant energy cost

See attached....SDG$E(San Diego, CA) raised the minimum tier from 12 cents to 15. We don't buy in and didn't run the AC much this year in baking heat, probably what most are doing, that and getting off the grid. This is sign of those still on the grid having to pay for the ones that are off. In KS, cost went down from 10 cents last year, to 9 probably in fear of going bankrupt like Cali. Lets see what they do with gas.

How about where you live, going up or down?

In Energy efficiency and durability | Asked By Terry Lee | Oct 15 14
10 Answers


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?



In GBA Pro help | 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.


In Mechanicals | 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?

In Green products and materials | 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...


In General questions | 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.

In Green building techniques | 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.

In Mechanicals | Asked By Gregory Worrel | Jun 1 14
10 Answers

Roxul Comfortboard - disadvantages?

I'm intending on insulating my 1950's Cape style house with exterior insulation. I've been planning on following the CCHRC's REMOTE wall assembly with an air tight membrane over the sheathing and 6" of EPS foam (2, 3" layers) then furring strips and siding.

In Green building techniques | Asked By Mark Fredericks | Oct 14 14
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