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1 Answer

Connecting ICF Foundation Wall + Timber Frame / SIP?

I'm planning to build a timber frame home soon (eastern white pine and SIPs) and have received a decent quote for an ICF basement.

I like the idea of efficiency in this combination and know that others have built this way but am a bit confused about how they connect? We are responsible for the foundation and first floor decking before the timbers arrive.

Does any one have construction details they could share for this (ICF wall, sill plate, first floor deck, post, blocking, and SIP positioning)? If not can any of you share your experiences with this?

Asked By Jeremy Mayhew | Mar 3 15
5 Answers

Calculating break-even point when mini-split costs same as running boiler

I have original steam boiler that is maybe 75% efficient (it is converted to gas 10-year old boiler). Recently, because we wanted AC, we installed air-source heat pumps (Mitsubishi MXZ-2B20NA with MSZ-GE06NA and MSZ-GE09NA head units). Basically one heat pump has one 6K and one 9K heads.

I am located in Boston. COP of Mitsu I calculated at 2.6 since HSPF is 8.9.

So what I am struggling to figure out is at which outdoor temperature it makes sense to switch from boiler, that costs $1.5 per therm at current New England prices, to mini-splits at current $0.243 per KWh.

Asked By Apollo S | Mar 2 15
8 Answers

Trombe wall (non-vented) with exterior moveable mode of insulation?

I am in the process of completing my energy efficient house design. Approximately 80% of the Building Envelope will be a Double Stud Wall Construction allowing for roughly 11" of Cellulose Insulation in addition to a 1" Rigid Insulation outboard of the Sheathing and inboard of the Hardie Cement Fiberboard Skin. The Remaining 20% of the Envelope will be Double Glazed Fiberglas Windows with emphasis placed on the South Elevation (Perhaps 60% on South, and 20% each on East and West). However, on the South Elevation I also have two sections of Trombe Wall - each 8' in width and 12' in height.

Asked By Thomas Tricarico | Mar 1 15
4 Answers

Double wall exterior sheathing

I am designing a near zero energy home in climate zone 5 and working out the details for a double wall system.

There is a lot of talk about what kind of sheathing to use or not use due to the fact that the sheathing will be very cold. As I understand what I have read so far, it is recommended NOT to use OSB or foam but OK to use DensShield Gold, structural fiber board or plywood in Zone 5.

Asked By Terry Herschberger | Mar 2 15
9 Answers

Foil-faced batt insulation effect on wall construction?

I’m in the process of planning energy retrofit for my house located in Philadelphia (zone 4A)
Existing wall construction consists of t1-11 over 2x4 framing with foil-faced batt insulation. The plan is to add 2 layers of 2” polyiso to the exterior taping joints making polyiso my WRB. Is there any concern that moisture trapped in the wall cavity won’t be able to dry to the interior due to foil faced batt insulation?

thanks!

Asked By Michael Kalustov | Feb 27 15
4 Answers

Sturbridge, Massachusetts — electric boiler

Sturbridge, MA. Have abundant PV, similar to Ed Jones' question. Need electric boiler recommendations. 40 panel ground mount lease. Put in at the height of recent depression. VG deal.

Property has small slab, under 900' sqft,, 3'' foam under and sides. low e glass, 2x6 walls.

Have abundant solar PV, no electric bill, even this winter. I do clean the panels after storms.

Current fuel is wood, we do not need to discuss.

I would rather use up more solar electricity, instead of sell it back to the grid.

Asked By howard kelley | Feb 28 15
9 Answers

2/12 cathedral roof replacement

Hi,

I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

Asked By mark kessler | Feb 23 15
4 Answers

Possible electrical ground out or short?

On the 7th of January, my townhouse electricity started cutting out (around 7 times). There was some wind in the area and cold temperatures, near zero. It stopped and soon after I would get shocked if I touched a lightswitch or my pet's nose. My power usage has doubled, but that may be due to the temperature change. It is my first winter in this place. However in the past, I have never had such a huge increase in usage. It went from 537 kwh to 937 kwh and increased again this bill to 1087 kwh. Could a ground out cause the static buildup? (The floors are carpeted.)

Thanks.

Asked By Sheleen Feldhaus | Feb 21 15
1 Answer

To French drain & sump crawlspace next to full basement or not?

In my Frankenstein of the house I have three basements. Original one from 30s (concrete foundations and floor - full height) in the center of the long house. Also on one side I have 70s basement, that I want to finish at some point, since it has more than enough head room.

Both 30s and 70s basements have a sump. 70s basement has perimeter footer French drain that drains into sump pit with two pumps. 30s basement does not have footer drain, just the sump with lots of holes in the liner.

Asked By Apollo S | Feb 18 15
2 Answers

How to get rid of sour smell in new house with spray foam?

Home owner complaining about spray foam smell in new home !

Asked By Robert Cook | Feb 18 15
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