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5 Answers

Blower door test

I am new to the field. I just took my brand new blower door out of the box and ran my first test though tectite software. My official training is at the end of the month sooo until then I need some help interpreting the results. From what I understand my house "scored" fairly well. 550 on ring B for the depressurization and 650 on the pressurization. The results sheet also showed 18.6 CFM and .14 ACH on depress. and 20.9 CFM and .16 ACH on pressure. I did not close off any exhaust fans, return registers because nothing that I have seen/read said anything about that.

In General questions | Asked By Matt Edwards | May 5 12
14 Answers

Airstream renovation

Hi, I'm helping someone renovate an airstream, which is to be a non moveable, room near their house. The house is in upstate NY, on the border between zone 5a and 6a. It's completely gutted, so it's just an aluminum can at this point. The plan is insulate it with closed cell foam, 1-1 1/2" on walls and ceiling, 3" in floor. That's all the insulation the frame will allow, unless some more extensive modifications are done. It's going to be heated in winter with a small propane heater, designed for boats.

In GBA Pro help | Asked By Mark Zachelmayer | May 1 12
2 Answers

Who manufactures cost-effective triple-pane R-5 and low-e windows?

Does anyone know who manufactures triple pane R5 low E new construction vinyl windows?
Any advice on best rated new construction vinyl windows?

In Green products and materials | Asked By Anna DeBaugh | May 4 12
2 Answers

Does XPS foam insulation board off-gas VOC's?

Does XPS foam insulation board off-gas VOC's?

In Green products and materials | Asked By Steve Reynolds | May 3 12
5 Answers

Supply-only ventilation with dehumidifier ?

The house will be a 2200 square foot house in Zone 4A. At this time the house is planed to be as tight as I am able to get it with in reason.

My question is, is there any reason not to use the fresh air option on a stand alone whole house dehumidifier such as the Honeywell TrueDry 90 as the ventilation source ?

I ask as I know one of the bigger IAQ problems in the home will be humidity.

In Mechanicals | Asked By Jared Humphrey | Apr 29 12
5 Answers

Making exterior crawlspace foam more termite resistant

I"m building a tiny house in southern Illinois, zone 4, mixed-humid. Dry-stacked CMU crawlspace outside dimensions ~18' x 18' with 2" rigid foam for ~R-10. Since the interior & exterior of the block will be "plastered" with surface bonding cement (SBC), would the following work to inhibit termite entry:
1. Install the foam board with thinset mortar (1/2" notch) including to the footings?

In Green building techniques | Asked By Harlan Bauer | May 1 12
37 Answers

The example of the failed roof with the polyiso on the interior.

It appears this sandwich had fiberglass in the roof cavity?

I was thinking of using 1" poly iso on a cathederal ceiling to give a thermal break to the framing. Spraying poly iso 4" closed cell 2# foam in the rafter bay. Then adding the additional inch of sheet foil faced on the interior. With the closed cell we have never had a moisture problem occur. Our location is north eastern Pennsylvania. The roof system has ice and water shield on it. Our feeling is that the closed cell foam doesn't let any air leaks occur, keeping moisture out of the interior to exterior sandwich.

In Energy efficiency and durability | Asked By Joe Billingham | Aug 11 10
5 Answers

What works best under a foam exterior?

I've watched the videos on installing foam board on the exterior of a house but what does the foam sit on at the the sill plate? I'm leaning towards a metal drip edge but others use Azeck board.

The reason I ask is that the videos address the windows well but what about the doors. We are not planning on putting bucks at the rough openings of the doors, just the windows. Since the door frame will be hanging out over the foam I just wanted to know how to support it if I use a metal drip edge like in the videos.

I also need some advice on a bug screen, what should I use?

In GBA Pro help | Asked By john bell | Apr 30 12
0 Answers

A real use of GEO-T systems with 100%Priority HW series

Specifically who has installed systems with the full condensing series DeSuperheater-Priority HW On-Demand that as HVAC-GT-HW-Reclaims all of the heat from a cooling mode? It also acts as a DeSuperheater in heating mode, and can continue in a convection of hot water heating if plumbed for that. and other applications as well.

In Mechanicals | Asked By JP Jon Pierce | May 2 12
5 Answers

Attic HVAC and Radiant Barrier

As part of a major renovation/addition to our 1970 2 story colonial house, we're isolating the 2nd floor HVAC and adding a second zone for it, and the contractors want to place the equipment in our unconditioned attic. It get's pretty hot up there in the summer (even though I live in NJ), and I want to do what I can to maximize the efficiency of the HVAC equipment in the attic.

In Energy efficiency and durability | Asked By Eric Lavitsky | Apr 30 12
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