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1 Answer

Vapor barrier or no vapor barrier?

I cannot seem to find a definitive answer to my question. I own a family campground in western NY which is open from May 1st through mid October. The main building is an A Frame with wings on both sides of the "A". There is no insulation and the inside of one of the wings is unfinished, the ceiling is roof sheathing and rafters. The building is closed during the cold winter months while I sun myself in Florida so heating is not needed. I do want to add air conditioning to make the space more usable during the hot, humid summer months. I am so confused about the info I read on how to insulate.

In General questions | Asked By Richard Deschenes | Sep 29 16
1 Answer

Most efficient use of 3/4" polyiso on exterior (polyiso is foil faced on both sides)

My home is standard built- 2x3's 16" oc w/craft faced fiberglass ins not very well installed( gaps,etc.). I have enough 3/4" f f polyiso to cover it. FH's recent articles indicate Roxul batts would be best way to insulate, but I already have the foam.

In Energy efficiency and durability | Asked By Victor Brown | Sep 29 16
2 Answers

Bubble Insulation - Double Wall

Is double wall bubble insulation more effective than normal bubble wrap for insulating windows. The following is a link to the type of bubble wrap I am talking about:

https://www.uline.com/Product/Detail/S-20055/Bubble-Rolls/Super-Duty-Bub...

Thanks,
Rachel

In Green products and materials | Asked By Rachel Glube | Sep 26 16
8 Answers

Custom French trench drain design for specific soil & flooding

I live in rural CO and have a mix of silty fine dirt and clay in my yard. I get some standing water in this portion of my yard during Spring snow melt and flash rains. I also get some of this water (only 1" standing in 1/5 of area) minorly in my 50 year old, 4 foot high crawlspace. It travels under the footer which is about 48 inches deep and 10 feet away on the same side of the home where I have room to put the trench, same side the yard water stands.

In Plans Review | Asked By Andy Nels | Sep 28 16
6 Answers

Slab rebar

I am getting conflicting answers on a small house rebar schedule. Some contractors claim rebar is not needed, others say wire mesh if fine, others don't think #4 bar is needed and said #3 is fine, etc.

I called out for #4 rebar at 12" oc

Rebar costs = $4.70 per 20' stick (#4) (21x35 pad)
So on a 3 feet on center pad = 19 sticks or $90
On a 1 foot on center pad = 56 sticks or $263

That's a $173 difference, right?

In Green building techniques | Asked By Peter L | Sep 28 16
1 Answer

Is it a good idea to vent a bath fan exhaust out of eyebrow roof?

I originally liked the idea of venting the bath fans out a gable end of the house in order to minimize roof penetrations on the steel roof. I did some research into venting through the main roof soffit vents, and obviously that is not a great idea due to the possibility of drawing moist air back into the roof.

In Energy efficiency and durability | Asked By Adam Peterson | Sep 28 16
5 Answers

Ideal wall assembly for unconditioned shed

Most GBA discussions focus on conditioned buildings, but I'm curious about the performance of unconditioned structures.

AKA: What's the cheapest way to build a 100-year bike shed? = )

Say we're in climate zone 4c: lots of rain, but only below freezing for a few months.

Since the shed isn't heated, the sheathing will always be cold.
Cold OSB can be trouble (http://www.greenbuildingadvisor.com/blogs/dept/musings/how-risky-cold-os...), so maybe we should go with plywood?

In General questions | Asked By Kevin Lynagh | Sep 27 16
4 Answers

Insulating rafters in this area

Hi GBA,

I am working on insulating a bedroom and down to a few key areas. I have a set of built in shelves made from 3/4" pine flush with the wall and trimmed in. These are built into the area between a shed dormer and the end of the gable end, making that triangle shape (I think there is a technical term for the area, but I've never found it).

In General questions | Asked By G S | Sep 27 16
5 Answers

Should I put an A/C return in my encapsulated crawl that has a bit of a smell currently?

I am having a new HVAC pancake system (Trane XR17 and sdv9 furnace) installed in my crawlspace this week. The installers have removed a lot of existing ductwork and I can smell the crawlspace in the house above right now, since the air just flows up. At one point I had considered installing a return in the crawlspace along with the supply registers to help keep the area dry without a dehumidifier that I use right now, and also to take advantage of the "free" cooler air in the crawl in the summer months, but the current smell is putting me off.

In General questions | Asked By John Sexton | Sep 28 16
2 Answers

Looking for ERV install design suggestions

Hi,
I am looking to install an ERV (Renewaire EV90P) to my home and am struggling to find people both interested but also qualified (or interested) to tell me the best install configuration and why instead of just dumping the fresh air into the return plenum. I'm considering now doing it myself and having two return vents (kitchen and bedroom) and two fresh air grilles (living room and hallway). Already have 200 CFM range hood ducted to outside and a bathroom exhaust fan with 60 min. timer to let run extra time up to this point. Blower door test showed 1.9 ACH.

In Energy efficiency and durability | Asked By John E. | Sep 27 16
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