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3 Answers

Can anyone explain... ?

Can anyone explain when:
1. system capacity(A/C) greater than cooling load
2. system capacity (A/C) smaller than cooling load
3. The effect of on/off control compressor in this two situaltions TQ =) ?

Because the system capacity and cooling load can affect to the room temperature and the system......so I need someone Pro can answer this question..thank you

In GBA Pro help | Asked By HO Y NAM | Aug 28 13
3 Answers

Minisplits as heat in northern Vermont?

I purchased a 1976 ski house in Northern VT last summer. It is ~2800 sq. ft. with a finished mother-in-law apt. in the basement which I have not been using as it is freezing and damp.

The furnace is a retrofit 2010 Airco oil burning forced hot air furnace that has extremely poor duct work. Unfortunately the ductwork is buried in a sheetrock basement ceiling (of which I think I'm gonna have to tear out to get to it). My home is poorly insulated with ~ 6inches of pink in the attic.

In Mechanicals | Asked By Mark Leipert | Aug 26 13
0 Answers

Green wood sealer

I am looking for a green good quality sealer for wood window sills and vertical trim. Has anyone tried the Envirolast XT, or Target Stays Clear EMtech EM2000vxw or the Benjamin Moore Stays Clear Acrylic Polyurethane all listed in the product guide here? Do they stay clear and how is the wear and water resistance?



In Green products and materials | Asked By Patrick Walshe | Aug 27 13
1 Answer

Insulating under house

I have been trying to do some upgrades to my home and the next big project will be to insulate the underside of the house, currently there is no insulation and it is ventilated. I have done some research and it appears the best solution will be to seal the vents seal everything with a minimum of a 6 mil plastic and insulate the foundation walls. Here is where i feel like my house may have some special circumstances. The house is setting on quite a hill and part of it has been dug out. At one end there is a 4' to 5' crawl space that is about 1/3 of the length of the house.

In Energy efficiency and durability | Asked By Michael Holloway | Aug 27 13
3 Answers

Can I retrofit an expansion joint between a driveway & house where none exists?

I recently had a new driveway installed where the contractor did not follow our ‘verbally agreed’ understanding that expansion joints were to be used against all permanent structures (this was my mistake).

Is there any method your aware of that I can cut the concrete away from the house ¾” and fill with an equivalent product that would serve as an expansion joint?

In General questions | Asked By David Reese | Aug 26 13
3 Answers

What is the best option for dryers?

In a passive or near passive house (ACH < 1), what is the best option for a clothes dryer that is easily available in the U.S., if used only infrequently (2-4 times per month), with the normal approach being hang drying:
a) regular dryer with outside vent (hole in the wall and heat loss)
b) regular dryer vented in house through water (humidification issues)
c) condensing dryer (more issues mechanically and longer dry times -> more electricity use)?

In Mechanicals | Asked By Phil Lawson | Aug 26 13
13 Answers

Rigid foam insulation advice


I need to replace some siding on my house so I was thinking this would be a good opportunity to add some insulation. I have done quite a bit of research and it seems adding some rigid foam would be a good way. I thought about just having some dense pack cellulose blown in to my walls but that doesn't appear to be worth it since there is already fiberglass in the 3.5” bays.

In Green building techniques | Asked By Pete B | Jul 17 13
1 Answer

Are two layers of XPS separated by T1-11 OK?

I am re-siding my attached heated garage with wood clad siding to match the house. The current siding, T1-11 (plywood siding), will not be removed as I need to side over the top of the T1-11. Because the windows and doors are reset to a plane that matches the house, I need to use two-inch thick strapping over the T1-11. Instead, I am considering adding 1 inch of XPS over the T1-11 and using one-inch strapping.

In Energy efficiency and durability | Asked By Braden Enroth | Aug 25 13
9 Answers

Sound insulation for existing apartment interior wall

My apartment has a common wall with a neighbor that has poor sound insulation consisting of a thin fiberglass batting. I can hear conversations taking place on the other side of the wall. It's got to be reciprocal, right? When this room was built above the garage, we had cellulose insulation blown into the exterior walls and ceiling. At that time I had no idea how bad the sound insulation was between the two apartments. The contractor said that they couldn't blow the insulation into the common wall because of existing fiberglass batting insulation in that wall.

In Green products and materials | Asked By Daniel Weiss | Aug 21 13
2 Answers

Used XPS Roofmate insulation and IAQ

I want to insulate my basement walls with XPS. I noticed that there are several places where I live selling used XPS insulation. I wouldn't think twice about using it in the same application, however in an interior space, I am not sure if it would "smell" or produce IAQ problems.

Does anyone have any experience with this?


In Green building techniques | Asked By cory b | Aug 24 13
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