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8 Answers

Basement insulation (hybrid) - guidance needed

I am in the process of installing basement insulation in a new construction. I am looking at cost effective methods. I have 145' of below grade basement wall (9.5' tall). I have had the builder install a small amount at this point in one of the "immediately finished areas" approximately 30' x 9.5'.

Here is what I have so far (PLEASE COMMENT ON THIS)

ABOVE GRADE LIVING AREA 2x4 walls(scheduled insulation):
3.5" open cell in walls
R49 fiberglass blow in ceiling

ABOVE GRADE GARAGE 2X4 WALLS (scheduled insulation):
R13 fg batts in exterior walls
R19 fiberglass blow in ceiling

In Energy efficiency and durability | Asked By Jeremy McGill | Dec 28 14
2 Answers

Hybrid heat-pump hot water heater cooling effects

We have a GE hybrid heat pump hot water heater in the non-partitioned 1100 square foot basement of our pre-certified PassivHaus home in northern NJ.

We've found that when it's operating as a heat pump, it exhausts enough cold air that it actually cools the basement significantly.

In PassivHaus | Asked By Len Moskowitz | Dec 31 14
2 Answers

Shell insulation

Having researched this sight for all related information on a new house in the mountains of the southwest in region 5, I have a few unresolved questions.

In Energy efficiency and durability | Asked By r ferd | Dec 31 14
1 Answer

Insulating interior foundation footings

Perusing the GBA construction details, I did not see this addressed. I have an addition which calls for 3 internal posts which should have footings as they hold a significant roof load. I am in 4 ft frost depth country. I could probably avoid the question by making the wall they are in a load bearing wall which should spread the load out negating the need for any footing, but future owners are bound to cut the wall out and have the roof come down.

In Green building techniques | Asked By Keith Gustafson | Dec 31 14
8 Answers

I need to replace a 75-gallon water heater. What are the options?

Gas versus electric or tankless.

In General questions | Asked By Rick Williams | Dec 27 14
2 Answers

Need a furnace/AC for an apartment

I'm a senior citizen on fixed income and just bought a 75 year old 2-family to help with expenses. I am living on first floor and have a 500 sq ft apartment upstairs. I added central AC to existing gas furnace, but at present I control the tenants heating and cooling. Most people love the apartment, but not me controlling their environment. My heating guy said there is no way to give tenant their own heating/AC unit using the existing ductwork. Does anyone have a suggestion, especially a "green" suggestion?

In Mechanicals | Asked By Brenda Fernandez | Dec 30 14
5 Answers

Can someone shed some light?

I'm at the point in my PGH construction when we need to select light fixtures. We plan several recessed lights above the kitchen counter and island. We need about eight to ten fixtures. Above the ceiling is a utility chase, with air barrier and insulation above that, so we're not concerned about the usual recessed can air sealing issues. We just want unobtrusive lights.

In General questions | Asked By stephen sheehy | Dec 27 14
10 Answers

Not a green area, but seeking advice on HVAC issue, if someone has time.

Need help from Pros here on what to do.

Had an attached closed porch gutted a few years ago. Was never insulated, connected to the kitchen, with an entry door. Had the porch gutted, re-studded insulated, and had a half bath in one part put in, and the other open area just for storage.
They punched thru an old basement window under the porch (was a basement window on that side of house until the old porch was added on decades ago, but was boarded up). Under the porch is the ground, dirt. the siding does go down to the ground on the porch.

In GBA Pro help | Asked By Dave Mac | Dec 29 14
11 Answers

Is a double stud wall with wood and steel studs a good idea?

I am an architect from Toronto. I designed a one storey addition to an existing brick house. I am putting 3" of rigid insulation on the outside of the new building envelope and a double stud wall using 2"x4" wood stud for the outter stud and 2-1/2"metal studs on the inside as a chase space and using plywood between the 2 stud walls as vapour barrier thus eliminating 6 mil vapour barrier. I am insulating all stud cavities with roxul.

Do you see a problem in this assembly? Why is this assembly never done?

Thanks for your review and expert opinion in advance.


In Green building techniques | Asked By Lowell Lo | Dec 29 14
2 Answers

Does air leak in/out of HVAC ducts located under a concrete slab?

The supply HVAC ducts in my house are under the slab (flex return ducts are in attic), which I know most building scientists recommend against. The supply ducts are made from 10' long sections of PVC pipe which connect to galvinized steel floor outlets that are generally located under windows on the perimeter of the house. As part of my house air sealing project, I applied duct mastic to the seams of one the floor outlets and by reaching my hand down to where the PVC connects to the galvinized steel outlet.

In Energy efficiency and durability | Asked By PAT DONAHAY | Dec 29 14
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