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0 Answers

Triple Pane - Bristol Windows?

Anyone hear of Bristol Windows out of PA? They make a triple pane window but looking at the frame profile section compared to a European triple pane window, it's a night and day difference. The European frame is way beefier and reinforced with steel.

Just curious if anyone has seen these windows up close or used them?

In Green products and materials | Asked By Peter L | Jan 14 15
19 Answers

2 x 8 stud walls, or staggered?

Southwest Nebraska - Zone 5B - I experience all four seasons. Hot summers that can be humid some years. Cold winters.

Designing my home to build. Trying to determine which is the most cost effective method to do the walls. I am young, and intend on living in this house for a very long time.

In Green building techniques | Asked By Nicholas C | Jan 7 15
44 Answers

Disappointing phantom load on 27.2 SEER Fujitsu 9RLS2 minisplit

Looking for anyone with measurements of their mini-splits phantom and idle wattage use.

My newly installed 9RLS2 is using 80 watts, both when off and on but not running.
Other measurements while operating have been in spec range and are fairly impressive.

So I take it that SEER and HSPF ratings must not effectively measure/include phantom or idle loads. Heck just the fan at full speed uses only 25 watts

In Energy efficiency and durability | Asked By bob coleman | Jul 12 13
11 Answers

Boiler water temp not matching aquastat setting

I have a hydronic heating system- mostly cast iron radiators and a couple cast iron baseboards and 3 copper fin baseboards. Aquastat is set to 190*. Water temps only get to 150* before the boiler shuts off. Radiators throw heat, but the baseboards need hotter water to be effective IMO. In any event, I'm not sure where to look first. Can this possibly an issue with my programmable thermostat? The room reaches the temperature it need to, to satisfy the thermostat. Thanks

In Mechanicals | Asked By Ric Pasqua | Jan 12 15
2 Answers

Whole R value 2x8 vs 2x6

I have been studying up on the building science High R value wall study and am trying to wrap my head around why the whole R value of a 2x8 wall appears to get a much bigger penalty when it comes to whole R value than a 2x6 wall. I was thinking must be extra thermal bridging somehow, but even if you start throwing XPS on the outside it doesn't seem to change things much. What am I missing here

Figures from BuildingScience High R values Report

2x8 advanced frame wall with R31 blown in fiberglass
R31 insulated value
R22.2 whole R value
Whole R value difference R8.8 or 28%

In Energy efficiency and durability | Asked By Jeremy Coenen | Jan 13 15
11 Answers

Roof Trusses 4' oc?

Would roof trusses spaced 4' oc fall outside prescribed methods for stud construction of a house in the 2012 IRC and therefore require approval from an engineer (other than the engineers at the truss manufacturer)?

In Building Code Questions | Asked By Jeff Cooper | Jan 9 15
8 Answers

Radon mitigation and fresh air supply combined?

Hello, if a home tests positive for radon and also would like to have an ERV & fresh air ventilation system, can these things be combined? In other words, can I tie a subslab depressurization system into a the ERV and fresh air system? Alternatively, is there any evidence that a moderate radon problem (4.1) can be mitigated with fresh air ventilation only?

In Green building techniques | Asked By Ryan Griffin | Jan 12 15
2 Answers

Cathedral attic moisture

I have an attic converted to living space where the roof is also the cathedral ceiling. Most bays go from soffit to ridge and are insulated with fiberglass and a foil barrier with a Duravent installed so that there is always an airspace from soffit to ridge. Those bays are mostly fine. The areas I'm having a ton of ice and moisture on the sheathing is where the bays are interrupted and there is only a ridge vent. Should I fill the bays solid with spray foam? Or should I at least foam up the ridge vent from the inside on those bays?

In GBA Pro help | Asked By steven pereira | Jan 13 15
6 Answers

Closing vents in unused rooms

My local utility had the following info on it's web site regarding closing vents in unused rooms. Any contrary thoughts on this?

"It’s true that closing a vent or two may reduce the furnace’s efficiency slightly. But if you’re closing a vent to avoid heating an area that doesn’t need to be heated, the energy you save will be greater than the energy lost due to the slight increase in inefficiency.

Bottom line: If you don’t need to heat a room, close the vents in that room."

In Mechanicals | Asked By Stephen Martinson | Jan 5 15
12 Answers

To insulate pipes or not to insulate pipes (hot water radiators)

I live in a 145+ year old house in NJ. I have 2 boilers in an uninsulated basement with 5 zones plus an indirect water heater, 4 zones are hot water radiators & 1 is radiant floor heat. There are about 14 big cast iron radiators in the house which is to say a lot of pipe running all around the basement of different sizes and material (mostly copper also black pipe, galvanized ?) The reason I mention all the zones is because each one has its own pump and different run of pipes to illustrate how much copper we are talking about.

In General questions | Asked By Dan N | Jan 8 15
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