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3 Answers

Best duct choices for ERVs and ventilation fans: PVC?

I am installing two Panasonic ERV's and two bath fans in a new house in climate zone 4C. Most mechanical contractors in this area use insulated plastic flew duct but I am worried about its longevity and off gassing. I am curious what duct material others would use.

Metal pipe seems best but more of a pain to seal and labor intensive.

I have heard of people using 4" PVC pipe to vent there ERV's. Does anyone have experience with this? Would off gassing of the plastic be a issue for the intake on the ERV's?

Would PVC electrical conduit be any different then PVC drain pipe?

In Energy efficiency and durability | Asked By Kail Zuschlag | Jan 18 16
6 Answers

Building new house, need suggestions on heat calc figures

Hello, I am new here. I am behind in my typical research based approach (I have been distracted by other pressing construction problems) but I am about to break ground on new construction and it occurred to me that I under-researched the subject of "heat loss calculations".

In Energy efficiency and durability | Asked By Bradley Lepkowski | Jan 18 16
6 Answers

Asbestos tiles - how much cracking is too much?

I've learned that I have floor tile in my basement that might contain asbestos. I was told as long as I don't disturb them I really have nothing to worry about.

However, a lot of them are already cracked & they crack even further the more I walk on them. I've swept up the ones that crack into small pieces, but for the larger ones I leave them be.

Question -

In General questions | Asked By j pritzen | Jan 17 16
24 Answers

Proper HVAC registers and diffusers to reduce temperature stratification

I live in a house built in the 1950s heated by forced-air from a gas furnace. This is a single story house with basement. Basement is not heated, but is insulated along its perimeter with fiberglass. The main floor has 8 foot ceilings.

Cold floors have always been a problem. I realize the basement not getting heat probably contributes the most, but with some air temperature measurements, I measured high temperature stratification:

Floor (0"): 59F
Thermostat (60"): 68F
Ceiling (96"): 72F

In General questions | Asked By j pritzen | Jan 5 16
3 Answers

Airtight home - fresh air? Dehumidifier?

We recently built a lake house with foam insulation. This was my builders first foam house. the house has high humidity of around 56%. The wood floors have started to buckle in several area. I'm being told we need to install a dehumidifier but I'm also concerned about the lack of fresh air. My question is will a dehumidifier be enough or will I need to install additional equipment to balance fresh air into the house? I'm looking for advise before giving approval.

In Green building techniques | Asked By Kurt | Jan 19 16
33 Answers

Instead of triple pane windows, why not double double pane?

An idea I had for putting in fixed pane windows is that instead of installing a high quality triple pane window, why not install a cheaper/lower quality double pane on top of each other? There would be an air gap so there would be 3 air gaps. The idea behind this is that it might save money while improving performance.

In Green building techniques | Asked By Dave R | Jan 11 16
10 Answers

Drying out a wet dense-packed cellulose wall

What rules of thumb can I use for when a dense pack wall will dry out itself, and when insulation must be mechanically removed? Here in a 1938 stucco home.


In Energy efficiency and durability | Asked By Bryce | Jan 11 16
10 Answers

Gap or no gap?

I have a 10" cinder-block wall (1970's) which I am insulating on the inside like this:
[Cinder Block] [2" XPS Foamboard] [3/4" Gap] [2x4 frame] [Fiberglass batt] [Drywall]

Question is should I have a 3/4" gap? I read on this forum that the 2x4 framing should be mounted "tight" against the 2" XPS Foamboard.


In General questions | Asked By Russell Torlage | Jan 18 16
4 Answers

Past experiences in upgrading wall insulation of a (solid) brick building?

I've learned that even with all the energy-efficient, air sealing, etc..stuff that I do in my house, that until my wall insulation is upgraded, I will be uncomfortable because of convective loops.

The walls from exterior to interior consists of:
a) two-wythe brick
b) 3/4" - 1" kraft faced fiberglass bat (not tightly installed)
d) drywall attached to brick with furring strips (no wall)

...which of course is the worst for a brick building.

In General questions | Asked By j pritzen | Jan 17 16
5 Answers

JM Spider Spray Fiberglass Insulation


In PassivHaus | Asked By Jonathan Lawrence CZ 4A New Jersey | Jan 18 16
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