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2 Answers

How do I find an independent energy rater that is familiar with up-to-date heating & cooling systems for a PGH?

Energy modeling confusion. How do I find an independent energy rater that is familiar with up-to-date heating and cooling systems for a PGH?

We are designing our own home and have read the blogs supporting and discouraging the use of energy modeling. How do we find someone to do an energy analysis who is not selling a specific HVAC product but can recommend an HVAC system that's appropriate for a PGH?

In Mechanicals | Asked By russell berenson | Mar 26 14
15 Answers

Stopping log home heat loss

Built the dream log home and now face the heating nightmare in Climate Zone 7. A masonry heater reduces the heating load of my in-floor heating system by half but without it my heating bills avg $500/mo. Here is my wild idea to reduce heat loss:

1/2" or 1" rigid foam against interior of perimeter log walls
Log siding nailed against rigid foam

In Energy efficiency and durability | Asked By Adk Homeowner | Feb 26 14
1 Answer

Best bang for the buck: insulation choices in a story-and-a-half home in Zone 5

Hi there, I've got a 2500 sq. ft. home that I need to make some decisions on in the near future. I currently have the home gutted down the studs. The exterior walls are 2x6 and the ceiling joists in the roof are 2x6 as well. The house was insulated with open faced batts with a foil backed drywall used as a vapor barrier (I assume). The 2x6 attic joists in the second story were insulated with a combination of faced and unfaced batts. The kneewall was insulated and a plastic barrier was attached to the back side of the kneewall. I've since ripped all of that out.

In Energy efficiency and durability | Asked By James Money | Mar 25 14
5 Answers

Vicwest AWIP R-value

I'm insulating using foam from factory rejects of Vicwest AWIP roof panels. They are ridiculously cheap (7 cents per board foot) and the seller claims an R value per inch of 7.5

According to the manufacturer's specs, the panels are injection moulded polyisocyanurate and R per inch is 7.9 at 40F and 7.1 at 75F. This contradicts research cited here that polyiso loses R value with colder temperatures and starts around R6/inch. Vicwest seems to have the temperature coefficient backwards.

In Green products and materials | Asked By Jonathan Dalton | Feb 11 14
9 Answers

Minimalist on top of slab insulation options

Hi all,

I have an existing 1970s structure with a 42" below grade basement slab. I'm re-doing the flooring in the basement (settled on cheap laminate over expensive stained and polished concrete) and am wondering about getting a tiny bit of insulation on top of the slab before I install the laminate.

I have a 91" ceiling height. so I don't have the head height to consider any of the lovely options described in the lovely GBA q&a here such as 2" of XPS and an inch of plywood.

In Green building techniques | Asked By Keith H | Mar 17 14
3 Answers

ERV a bad choice for a tiny house near Toronto?

I am building a 187 square foot tiny house for my family of 3 in Barrie, Ontario and have some questions about ventilation. The house is decently well insulated and airtight, with 6 ½” inches of XPS on the walls and roof, 5 ½” in the floor, and a Solitex Mento 1000 exterior membrane.

In GBA Pro help | Asked By Travis Marttinen | Mar 25 14
11 Answers

Insulating a 1929 craftsman bunglow in San Diego

The exterior walls have no insulation, vapor retarder or barrier. Is an exterior barrier/retarder required when insulating walls? If so, what products are available that doesn't require removal of siding to install?

In Green products and materials | Asked By patrick owen | Mar 24 14
13 Answers

Looking to do away with my oil heat

Hello all, I was looking up information on Air Source Heat Pumps/Ductless minisplits, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to cut WAY down on my oil heat, so bear with me as this might get a little long.

In Energy efficiency and durability | Asked By Khouri Rice | Mar 24 14
11 Answers

Do bulb replacement programs save energy in heating climates?

My question is specifically about heating climates with a predominance of electric heat.

If a house is heated with 100% efficient electric heat, such as baseboard or panel radiators, does replacing incandescent bulbs with CFL or LED bulbs save electricity? Can anyone point to a study that has looked at this issue?

If a house is heated with <100% efficient electric heat (i.e. an electric furnace with ducts in the crawl space with the (perhaps) typical ~30% duct leakage, could bulb replacement actually be a step in the wrong direction?

In Energy efficiency and durability | Asked By David Meiland | Mar 21 14
4 Answers

Radiant heat improvement?

I have an ongoing renovation of my own house but any info will certainly apply to other projects that fall into this same scenario or possibly another job that I or others may encounter.

The current conditions are:
1. Hydronic radiant heat installed under existing 3/4" board sheathing which is under two layers of wood flooring for half of the area, the second half is tile underway, same build-up thickness.
2. 5 loops cover 925 s.f of first floor area, fairly equally sized loops.

In Mechanicals | Asked By Robert van Wert | Mar 24 14
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