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1 Answer

Insulating existing barn with board and batten siding?


I have an existing post and beam barn in Massachusetts that my wife and I would like to convert to a workshop/studio space. It's clad with existing rough cut vertical pine siding to which I plan on adding vertical battens to seal it up better.

I would also like to insulate. Preferably with Icynene to get a tight seal and discourage rodents from nesting in the exterior cavities. The Icynene dealer suggested open cell and said that a weather barrier isn't necessary(?)

In General questions | Asked By Evan Halstead | Sep 8 15
2 Answers

How long will closed-cell polyurethane foam retain its greater-than-5 R-value?

The laws of physics and thermodynamics state that a stable R-value higher than about 5 is impossible to achieve when using air as the trapped gas in an insulating material due to the thermal conductivity of air itself. Most materials using air will be lower than than due to the thermal bridging of the structure itself, which is why EPS has an R-value that tops out in the mid 4s. XPS, polyiso and polyurethane boast higher R-values than this because the trapped gas is not air, but rather, some blowing agent with a lower thermal conductivity than air.

In Energy efficiency and durability | Asked By Nate G | Sep 8 15
2 Answers

Why would someone buy a heating (gas fuel) and cooling package unit?


I recently moved to CA and have started seeing a lot of homeowners installing heating and cooling package units, usually installed on the roof. These systems are gas-fueled, with a max AFUE of 81 or so. Why would someone buy one of these units instead of a full Air Source Heat Pump to do heating and cooling?

For example: http://www.lennox.com/products/packaged-units/LRP14GE/

Thanks for your help!

In Mechanicals | Asked By Whitney Larsen | Sep 8 15
6 Answers

Cavity insulation with exterior rigid foam

I'm looking for advice on stud cavity insulation. Walls will be (from outside in) LP smartside lap siding, 3/4" rainscreen gap, 6" EPS foam (R-24), self-adhering vapor/water/air barrier, OSB, stud cavity, then interior wall covering which will be either T&G pine or drywall with latex paint. My main floor walls are 2x4 and the basement walls are 4' below grade ICF and 4' above grade 2x6. I live in zone 7a - eastern North Dakota.

In Energy efficiency and durability | Asked By Adam Emter | Sep 5 15
2 Answers

Is closed cell foam insulation worth the cost for a 75 year old home with 2x4 exterior walls?

I am remodeling my 75 year old home. I am gutting the interior walls and adding a full dormer. The exterior walls are 2x4. Is it worth the cost for closed cell foam insulation or is a traditional fiberglass insulation sufficient? Thanks, Paul

In Energy efficiency and durability | Asked By Paul Hanson | Sep 6 15
9 Answers

Improving hot water heat pump tank efficiency with free dryer heat

Hi. I have been thinking about how to improve my GE electric hot water heat pump efficiency, particularly in the winter months. It is located in a very well insulated utility room off the garage (larger than recommended minimum volumes). The by-product of using the heat pump is cool, dry air, which in turn creates a cold room calling for accessory heat to warm the room back up to temp for the heat pump to then work efficiently again. I find the room temp is fluctuating up and down in conjunction with the use of heat pump this not making it as efficient as it could be.

In Energy efficiency and durability | Asked By Matthew Michaud | Sep 7 15
4 Answers

Does anyone have updated (current product information) on water heaters with heat pumps?

I am looking for a DHW heater (with heat pump) which will service both DHW and a radiant floor system? The project in question has approximately 1300 sf radiant floor system and having one appliance to service both efficiently would be very beneficial.

I’ve looked at the Sanden Eco (good information here in this forum) but it’s too late for the current project to design an exterior heat pump into the residence exterior; but I will certainly consider this next for future cleints since they will be available (I'm told) at the end of this year.

In Green products and materials | Asked By Caroline Di Diego | Sep 7 15
10 Answers

Thoughts on gas lanterns in green homes?

I am considering installing gas porch lights (wall mounted) when we do a deep energy retrofit of our 1888 victorian home. I think the look is great and cost is reasonable but I am debating the contradiction it would present by using such an inefficient lighting method on a high performance home. Do you guys have any opinions? thanks in advance.

In Green building techniques | Asked By alok khuntia | Sep 6 15
4 Answers

Vented attic vs. a sealed, non-vented, airtight attic

I'm building a new home in Miami, Fla.

An insulation contractor advises me to eliminate the planned roof & soffit vents and seal the attic with foam.
What are the Pros and Cons for maintaining attiic ventilation, and eliminating it?

In Energy efficiency and durability | Asked By Calvin Smith | Sep 1 15
8 Answers

Any hydronic system controls with low standby electricity consumption?

I was feeling good about the changes I'm making to reduce the electricity consumption of my hydronic system: a Grundfos Alpha ECM pump that is consuming only 16 W when it's running, and Taco "sentry" zone valves that use about a watt when on. But I measured the power consumption of controls last night, and it can add up to almost as much as the pump: 3 W for an aquastat, 6 W for a Taco "switching relay" circulator control with one zone on, and 4 W of standby power for the 40 VA 120:24 VAC transformer that powers the zone valves.

In Mechanicals | Asked By Charlie Sullivan | Sep 2 15
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