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2 Answers
Condensing boiler in mechanical room outside building envelope

I have been asked to insulate a new home on the coast of Maine. The home is super-insulated and will have 12" thick walls, insulated slab with great solar exposure.

the mechanical room, is a 10'x10' stucture that is attached to the building but has its own roof and only 2x6 walls. It has not been air sealed during construction but the plan calls for cellulose in the walls and ceiling.

In Mechanicals | Asked By bo jespersen | May 10 10
5 Answers
Energy efficiency and quality of life in a northern exposure lake house? Or pick a different view?

Exposure as it relates to energy efficiency and guality of life

In Energy efficiency and durability | Asked By shoresea | May 10 10
2 Answers
External insulation — 10 cm vs 8 cm. Will it make a big difference in energy use?

Hi,

In Energy efficiency and durability | Asked By Canan | May 10 10
7 Answers
Vertical trusses for insulation

I recall an article in FHB years ago about an energy-efficient house built as a demonstration in Canada. Rather than foam, the exterior walls were built with a truss system that was then filled with blown-in insulation.This would not eliminate thermal bridging-nothing does entirely-but it would offer an alternative to foam.Any thoughts?

In Green building techniques | Asked By Brian | May 8 10
2 Answers
What is HRV

Please explain what HRV means.

In General questions | Asked By John Hughes | May 10 10
5 Answers
Green Roof components supplier recommendations?

I am searching for a supplier for Green Roof components (geotextiles, plastic drainage tiles, edging etc) for new residential "flat" roof construction. Are there any American made systems out there available for smaller (1300 sq ft) installations? So far I have found Conservation Technology's Optigreen system which is imported from Germany and available in small quantities to contractors and the diy. This is for an "extensive" green roof, ie 4" of soil planted with low growing drought tolerant vegetation.
Thank you for your input, Lillian Maurer, Hudson Valley NY.

In Green products and materials | Asked By Lillian Maurer | May 6 10
1 Answer
Old welded Ductwork

I am working on a renovation project of an 1890's residence - project has a tight budget but high energy efficiency and green remodeling goals.

In Green building techniques | Asked By Anne Lee | May 9 10
3 Answers
Has anyone done a cost difference interior/exterior energy effeciency retrofit?

Hot climate!
Exterior: Remove brick, add something to the slab to move the brick step out to new location, add two layers 1-1/2" ridged insulation re-brick
Interior: remove existing gyp wall, add 2x4 stick wall with new 2x4 offset from existing studs to minimize direct connect heat path from outside. move existing batt insulation to the attic, move existing electrical to new studs, add closed cell expanding foam insulation, re-gyp/tape paint, trim.

Lossing 4" of living space at each wall.

In Energy efficiency and durability | Asked By Eric Albright | May 6 10
11 Answers
Sizing a Heat Recovery Ventilator (HRV)...can it be too big?

> My new house with in-floor radiant and basement is approximately 28,000 cubic feet. I calculated a 200 cfm HRV unit:

cubic ft of house = 28,000

28,000 x .85 (to account for interior walls and furniture) = 23,800

23,800 x .5 (air change rate) = 11,900

11,900/60 (to convert air changes per hour to cfm) = 198.33

> My HVAC guy recommends a 300 cfm unit and is not concerned with oversizing the unit as much as undersizing it (he's used to installing 2,000 CFM heat pump systems in a house my size).

Is there a problem with OVERSIZING a HRV?

In General questions | Asked By Frank | May 6 10
7 Answers
"Mooney wall " for greater insulation value

Has anyone had an experience using a "Mooney wall" in either new or retrofit application? I came across this webpage and found it to be interesting, but wanted to ask the experts here for further discussion of the merits of such an application.

http://www.builditsolar.com/Projects/Conservation/MooneyWall/MooneyWall.htm

In Energy efficiency and durability | Asked By JR | May 5 10
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