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3 Answers

ERV, HRV, Dehumidifier retro fit before finishing basement

Hi all, I'm new here. Please bear with me with lots of questions.

I live in Zone 4A, with humid summer (100+ F, at least 3-4 months AC time), cold winter (-10 -- 0 F, at least 3-4 months heating), and wet spring and fall. Our house was built about 10 years ago. It has 3 HVAC systems for 4000 sq. ft. and additional 2000+ sq. ft. unfinished basement. Two HVAC systems are located in basement while the third one located in a closet on 2nd floor.

In Mechanicals | Asked By Wendy D | Oct 25 14
1 Answer

Crawl space with dirt floor and spray foam

I have a crawl space that is covered by walls wood and parchment. Above it is the kitchen hence there are kitchen pipes there that never froze. My garden hose supply line has frozen a couple of times in the past. There is also force air duct work in there. I brought in a number of different insulators and there is no consistency.

In Energy efficiency and durability | Asked By Paul Staffieri | Oct 25 14
6 Answers

How do deviations in average winter temperature affect energy consumption?

Off the top of my head I would expect a five percent colder winter to cost five percent more for heating, all things being equal.

In Energy efficiency and durability | Asked By norm farwell | Oct 24 14
8 Answers

Calculating how much air needed to even out temps for minisplit

I'm building an 800sf 2 story house, R20 under slab, R40 walls, R60 roof, as airtight as possible, but likely just double pane windows (due to cost). 12% glazing, mostly on south side, w/ 4" slab on first floor. Using Marc Rosenbaum's heat loss spreadsheet, I get around 4000BTHU building load here in Portland Oregon at the 97% coldest day of 23F and a design temp of 70F, so a delta T of 47F.

In Mechanicals | Asked By Tom Frisch | Oct 23 14
6 Answers

Thermostats with radiant floor heating

I recently read an article comparing forced air and radiant heat energy use. The finding showed that the folk with radiant heat set their thermostats higher than for forced air. I hope that I am not being silly, but how can a thermostat on a wall respond to radiant heat? If one put a metal foil around the thermostat ,but let air flow occur, would the thermostat read a different number? I read in Mr Lyles masonry stove book that a cathedral that had radiant heating only had a 2 degree difference between the floor and ceiling (75 feet up).

In Mechanicals | Asked By Mike Legge | Oct 12 11
12 Answers

Flat roof insulation

I have built an extension to my house with flat roof, continuation of the existing house. The rafters are 16 in apart and there is 6 in left for the insulation under the sheeting. The plans are requiring R30 insulation and the building inspector requested hard foam Thermasheath- 3, 5 in thick, leaving 1 in for breathing. The drywall was not installed yet, when water from condensation came down all over the place. There are vents on both sides of the roof, in each bay under the insulation level, not allowing the hot air to escape.

In Energy efficiency and durability | Asked By Angela M | Nov 22 13
10 Answers

What kind of insulation would you recommend for a 20' shipping container being renovated into a home/studio space?

I'm renovating a 20' shipping container into a home/studio space and am wondering what would be the best "green" insulation to use. I will be doing some interior framing so would like to insulate the inside walls and floor. As well, I am building a green roof/deck that is framed using the structural strength of the container (no weight on the center of the roof) and would like to add insulation between the joist supports and deck floor (approx 3" - 9" above the container roof) and the steel roof.

In General questions | Asked By Sarah Beckstrom | Jan 19 14
4 Answers

Roof insulation

Home location in zone 2A Central Florida (Not on the coast). Having 2,053 SqFt living space w/above ceiling blown in insulation R-30 and an additional 1,027 uninsulated space. Fully vented at the soffet with minimal ridge vent. Soon to install 2 solar powered thermostat controlled 1600cfm roof vents. The wall construction is CMU block w/stucco finish. The roof is 6:12 pitch, Arch shingles over 30lb felt paper and OSB. The ceiling plane is tight.

In GBA Pro help | Asked By Steven Clark | Oct 24 14
3 Answers

Will spray foaming my basement rot my sill plate?

Hi Martin or whoever would like to add input to my query. I live in Eastern Canada near the coast in a Zone 6/7 environment. I live in an old house with an low ceiling unfinished basement that is freezing cold all winter.

In General questions | Asked By Chris McLean | Oct 24 14
1 Answer

Radiant Retrofit Best Practice

We recently purchased a home which had a radiant retrofit in the basement approx 10 years prior. Our first winter (last) I noticed some mold showing through the finished flooring (4' x 8' wheat board). Long story short, I found 2 screws had pierced the pex and slowly corroded over the years finally leaking and ruining it all.

The layout was 6" wide 3/4" hardboard sleepers glued and nailed to the slab with 1/2" pex between. Over the pex and sleepers, 12" wide aluminum flashing was stapled and then finish flooring. The slab is insulated (2 layers of 2" polystyrene under the slab).

In General questions | Asked By mie asdfav | Oct 24 14
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