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8 Answers

Unvented attic -- New roof, exploring options

Hi everyone,

We're in the process of getting our roof replaced on our 1964 single floor "rancher". The house currently has no venting at all in the attic and we're getting mixed responses from different vendors on whether we need ventilation or not. Read plenty of things online about the negative pressures that are typically created when using powered fans in the attic and would prefer to avoid them. Another installer recommended smart vents installed under the shingles and a new ridge vent.

In Energy efficiency and durability | Asked By Ryan Holt | Jul 16 16
7 Answers

Insulating a suspended floor: Caulk the seams or not, and is cellulose okay?

A friend of mine is building a tiny house on a trailer in Austin, TX (Climate Zone 2A), and has questions about insulating the floor.

First, should the seams of the floor framing be sealed with acoustical sealant before installing the insulation, to prevent air infiltration and increase insulation performance, or is some air movement good to prevent moisture accumulation and mold?

In Green building techniques | Asked By Michael Bluejay | Jul 16 16
9 Answers

I am looking for some advice on getting a construction loan

I bought 50 acres and have a mortgage on the land. I have spoke with a few local banks and am having trouble finding one to finance my building project. I am looking to be the GC in order to save some money and get things done right. So the bank that doesn't require a ton of money in savings won't let me GC it and the bank that will requires more cash than I have after buying the land. Is there a way to finance a new construction home and GC it with little cash? Or will I just have to wait it out another couple of years...

In General questions | Asked By ADK Creator | Jul 15 16
6 Answers

Basement Insulation - Remodel

I have a question I haven't been able to find a good answer to. I own a home in Minneapolis-St. Paul that has an unfinished walkout basement. Home was built in 1988. Basement was never finished. Basement is drain tiled with sump pit but no pump was ever installed. Nonetheless, the basement appears completely dry.

In Interior design | Asked By John N | Jul 7 16
2 Answers

Egress well draining, poor soil, no drain tile

So I think I have the worst possible situation for an egress window, but I'm hoping to install one nonetheless. I have clay soil with no exterior drain tile around my house and no interior drain system either. Luckily I've never had any water problems in my basement. I run a de-humidifier during the summer, but I've left cardboard boxes sitting on the slab floor for years and they've stayed in perfect condition. Also, I'm lucky enough to have long eaves at 30 inches that cover most of the well, and I have excellent grade-sloping (hillside) away from the well.

In General questions | Asked By Jason Adams | Jul 4 16
3 Answers

CertainTeed MemBrain

Can the MemBrain go over kraft-faced fiberglass? Would this be a double vapor barrier? My wall assembly is aluminum siding, a shiny like paper under the aluminum, 30-lb felt, and then shiplap sheathing over 2x4's . Zone 6A

All the major box stores only carry R-15 Kraft faced FG no unfaced.

In General questions | Asked By MS | Jul 16 16
2 Answers

New home windows

See sketch. Was told indivedual units are design pressure 50 when combined DP 25. Why and what can I do.

In General questions | Asked By Edward Serafin | Jul 16 16
3 Answers

Vertical exterior trim on outside corners on homes with exterior rigid foam

For an article on installing exterior corner boards on homes with exterior rigid foam, I'm soliciting photos or architectural details showing wide furring strips or other techniques to make sure that there is solid backing to allow the attachment of corner boards or siding at outside corners.

You can post your images here, or email them to me:
martin [at] greenbuildingadvisor [dot] com

Thanks very much to everyone in the GBA community for all your contributions!

In General questions | Asked By Martin Holladay, GBA Advisor | Jul 15 16
10 Answers

How efficient are recirculating kitchen range hoods with carbon filters at removing air pollutants from cooking?

I looked at a few of these filters for the recirculating range hoods and they didn't look all that impressive, but maybe I am looking at the wrong hoods. If passive houses are using recirculating hoods how well are the hoods actually working. Clearly there is a tradeoff for energy efficiency and range hood function. Is there any specific data on this? Are there certain types of carbon filters that work better than others? I am not talking about removing moisture or CO from gas ranges but more grease and other pollutants produced when cooking with electric ranges and ovens.

In Mechanicals | Asked By Dillon Vautrin | Dec 16 15
3 Answers

Building wrap: under the exterior foam, or over?

I am building a one story, unvented crawl space, vented attic 1350sqf home in zone 7, Northern MN. Basically going REMOTE. My carpenter and I were looking at the REMOTE manual today, and we noticed Tyvek building wrap was put on the sheathing before the foam was installed. I will have 3 1/2 inches of foam, 2" resting on top and even with the outside edge of my 2 1/2 inch ICF's, (both in and out) and 1 1/2 on top of that extending down under the ground level. All 3 1/2" of foam will extend up to the top of 16" energy heel trusses with blown cellulose in the attic.

In Energy efficiency and durability | Asked By Steve Vigoren | Jul 11 16
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