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8 Answers

Minisplit - One indoor unit for two adjacent rooms?

Do any of the minisplit manufacturers offer a wall mounted indoor unit that will service two adjacent rooms? I'm considering a minisplit to replace the gas furnace and a/c in my 1300 sq. ft. single level home in zone 3A (mixed-humid). Without a shared indoor unit on the common wall between two bedrooms, I might need five indoor units. The multizone minisplits seem to jump from 4 to 8 zones and the price jumps too. I understand the technical problems with one wall unit serving two rooms, but have any of the manufacturers solved them.

Asked By Steve Robertson | Oct 23 14
14 Answers

Window U-value comparison to wall R-value and window replacement

We have an 1870s Victorian farmhouse that doesn't have insulation in the walls, and to keep it simple, we cannot add insulation in the walls without going to great expense, more than we can afford.

Asked By Keith Miller | Oct 20 14
1 Answer

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.

Asked By Steven Clark | Oct 24 14
4 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.

Asked By Tom Frisch | Oct 23 14
2 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.

Asked By Chris McLean | Oct 24 14
0 Answers

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).

Asked By mie asdfav | Oct 24 14
3 Answers

Large structure with sealed attic / fiberglass

I have a 48x75 post frame structure with a metal ceiling. Prior to putting up the metal ceiling I installed a 6mil plastic vapor barrier. The entire interior is encapsulated with the 6mil plastic under corrugated barn/ag panel metal. I want to blow R60 into the ceiling, but my metal spans 8.5'. I am worried about the weight of cellulose. I used R-panel on the ceiling for a higher load rating and span, but I still think R60 with fiberglass would be much lighter.

Asked By W Ahrens | Oct 22 14
5 Answers

Insulation in old home repair

Hello, I own a 1931 home. I had a window leak it damaged the plaster on an interior wall, roughly a 2'x5' section. Behind the plaster and lath was a later of loose insulation and behind that bound newspaper. Much of the newspaper was rotted, as was a section of the wood behind it. The wood backed the exterior stucco. I removed the newspaper and wood. I am unable to replace the wood that backed the stucco.Instead and added 1" rigid foam.

Here's my question: What do I use next to insulate before I put on the sheetrock, faced or unfaced fiberglass...or something else? I live in Minneapolis.

Asked By Tom Ives | Oct 21 14
7 Answers

Attic insulation — existing

I have a 1800 sq. ft. ranch home built in 1969. Climate zone 5. Existing attic floor/ceiling area has a layer of 3" fiberglass insulation with vapor retarder facing the heated space. The second layer of insulation is a 3" layer of fiberglass with vapor retarder facing the attic area.

Both layers have been installed inside the joist bays and stuffed very tightly at the top of wall/ceiling intersection-no soffit vents in place. The roof has box vents and gable vents in place for ventilation.

Asked By bob prince | Oct 22 14
6 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.

Asked By Sarah Beckstrom | Jan 19 14
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