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6 Answers

Attic air handler: New system or unvented attic?

My house has 2 heat pumps with the air handlers in the attic.....in southern Florida.

Typical insulation could be improved.....the HVAC systems are 10 years old. Would I be better off putting in newer, more efficient HVAC system (current system is plain single stage, single speed) or changing the attic to foam unvented attic?

In Energy efficiency and durability | Asked By Steve Romero | Jun 26 14
2 Answers

Am I using RESFEN wrong?

I am attempting to model several options for replacing my house's windows and I'm getting slightly weird results.

This is the Albuquerque, NM area, which is a predominately a heating climate, but does have a cooling season, and gets lots of sun year-round. My cooling bills are very low since I use evaporative cooling, so I want to focus on reducing heating energy, leading me to want to maximize the free solar energy available in my sunny climate. However, I also want to alleviate the summer discomfort from the west windows overheating.

In Energy efficiency and durability | Asked By Nathaniel G | Jun 26 14
2 Answers

What is the difference between R-19 (for example) and a rating of R-3.44 per inch?

I am going to add insulation to the inside walls of an existing home. I want the best insulation (R-value), bur I don't know the difference between R-19 vs R-3.44 per inch, for example.

In Energy efficiency and durability | Asked By beverly bliesath | Jun 26 14
8 Answers

How to put rigid foam over brick then stucco the foam

I have a house in El Paso Texas that has a brick exterior. I would like to put 2" of rigid foam over the brick then stucco the foam. How should this be done? What type of stucco is best? I do not want to put the insulation on the inside of the house because it is a small house and it would take up too much room. The house has zero insulation. The house was built in the late 20's. What questions should I ask a company that would be putting on the foam?

In Energy efficiency and durability | Asked By Joan Proza | Nov 10 10
2 Answers

How much air does dense-packed cellulose leak?

I've been thinking a lot about dense packed cellulose and reading up on it's various properties. I found an excellent discussion on this same message board: http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an....

In Green products and materials | Asked By Josh Engle | Jun 25 14
2 Answers

How to prevent check valve malfunction in a hydro-air system?

I have a propane water heater with a loop to the air handler. Potable water goes through the coil. I noticed that my water heater would run twice an hour even though there was no demand. I guess I should have cleaned the back yard up before June. Anyway, I found the coil was not so apparently there was a convection loop happening. I closed the valve and all is well. My plumber says that since I have potable water running through the coil, I will always have this problem. Is that right? Should i stick some type of solenoid valve in the loop?

In Mechanicals | Asked By Walter Gayeski | Jun 25 14
7 Answers

Infiltration rating of ICF

I am working on a design using ICF for a new building. I am wanting to run some performance testing on the wall assembly, however I am not exactly sure what to put for the infiltration numbers. Knowing PH is .6, I have been using 1.5 for tight framed construction (hoping and assuming it can test lower), but what is a good number to use for ICF construction from footing to roof? All the rave is about the tightness, so is 1.5 safe or too high? I am also using the r value for the EPS for my number and not any "thermal mass" fluff as they like to claim.

In Energy efficiency and durability | Asked By Jesse Lizer | Nov 17 11
5 Answers

Vapor-permeable barriers and brick walls (MemBrain, Intello+, etc.)

I have a ~100 year old solid brick house in zone 5 - Northern IL ~1/2mi to Lake Michigan. The walls are 2+ courses wide with ~1" gap between.

We're slowly rehabbing the house floor by floor. And trying to decide what the best way to deal with air infiltration and vapor permeability. From my reading, it looks like I could put Membrain or Intello+ on the brick directly, then build a (non load bearing) studwall on the inside and insulate that.

Is there a problem with putting a variable perm barrier on a cold surface? .

In Green products and materials | Asked By Job Lenihan | Jun 22 14
16 Answers

Mechanical Ventilation in a Tight, Permeable House

Ok, I am going to thoroughly expose my lack of knowledge with this question (no claims to any expertise on my part), but I'm hoping that some of the experts here can comment on something I am thinking about.

In Mechanicals | Asked By Stephen Youngquist | Apr 16 14
7 Answers

Unsure about energy audit suggestions...

I apologize in advance for any length and confusion.

I'll describe the house:
Location is Mid-Hudson Valley NY.
2 story colonial (I moved in about 2004). I think it had been built for someone else in 2003. Appx.

In Energy efficiency and durability | Asked By Louis Aller | Jun 23 14
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