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6 Answers

Slab on grade thickness

Just a quick question on how thick the slab should be on a slab on grade house?...thanks,Bob

In General questions | Asked By bob holodinsky | Jul 9 14
10 Answers

Does anyone use hydronic underfloor heating systems to move passive solar heat around the mass?

I'm in the early stages of planning a new build. I'm considering a heat pump underfloor heating system in concrete slab. The house will be carefully optimised for passive solar gain as well. Has anyone heard of using the underfloor plumbing to move heat around the slab from areas receiving direct solar illumination to other parts of the slab?

In Energy efficiency and durability | Asked By Felix Collins | Jul 8 14
8 Answers

My rant regarding the energy efficient mobile/modular homes :-)

I do not understand why people are trying to reinvent the wheel regarding the actual construction of mobile/modular homes. They must have money to burn and time on their hands and that makes me mad because they are charging ridiculous prices.

In Energy efficiency and durability | Asked By Anneal G | Jul 1 14
23 Answers

For southern exposure, what do you think is the better glazing option: 1. U=.29, SHG=.49 or 2. U=.19, SHG=.37 ?

Both windows would be installed near Green Bay, WI, climate zone 6. The lower u-value window is vinyl and the other is fiberglass, but aesthetically, both are acceptable and equal for my tastes. The vinyl are manufactured by Wasco Windows (based near Milwaukee, WI) and the fiberglass alternative are Marvin Integritys.

The square footage of glazing along this wall is approximately 5.5% of the floor space. The finish floor will be a 5" concrete slab that will have no additional floor covering.

In Energy efficiency and durability | Asked By Rick Van Handel | Jul 7 14
0 Answers

Where to get Roxul Drainboard in 3.5 inch thickness?

I live near Rochester NY. I am building passive solar home. Does anyone know where I can buy Roxul Drainboard in 3.5 thickness on the east coast ? I have talked to reps from Roxul and can only buy a truck load . Hard for the owner builder to go greener when we cannot get the products. Does anyone know of any cooperative, business or homeowner that has it for sale? Thank you ! Zenith7

In Green products and materials | Asked By michael holler | Jul 9 14
5 Answers

Why hasn't this cathedral ceiling failed?

Climate zone 5, northwest Ohio. Evaluating options for improving a cathedral ceiling in this 1970's house.

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Jul 8 14
1 Answer

Rubio Monocoat vs. Safecoat Acrylacq for cabinets?

Hi there,

In working with a custom woodworker we are trying to build green cabinets (green from an air quality stand point). We are trying to decide on a finish for the hardwood doors of the cabinets. We were trying to sort out the differences between Safecoat Acrylacq or Vermont Natural Coatings to choose one of these.... but then.....Rubio Monocoat came to our attention.

I realize that it is a very different type of product than something like Safecoat Acrylacq (which is a water-based poly finish) -- I realize Monocoat won't have the sheen of a poly finish. I think that's OK with us.

In Green products and materials | Asked By Mindy Munger | Jul 9 14
1 Answer

Deciding between conventional heat pump and minisplits

I'm working with homeowners who are considering an HVAC upgrade for their new house, approximately 2,000 sq.ft. It's vintage 1970's, but we'll be doing a number of air-sealing and insulation upgrades. Eventually we'll have an HVAC design professional come check the place out, and make recommendations, but for the moment we're considering what options are out there. Currently, the house has the original forced air ductwork, with a new heat pump put in last year by previous owner. It's a Lennox XP14-042, with matching new air handler and resistance heat.

In Mechanicals | Asked By Andy Chappell-Dick | Jul 8 14
2 Answers

L shaped building/gable roof

I have been told that a home that is L shaped is much more expensive to build than if the extra space was just included in primary rectangle--no"L" The reason I was given is that the cost of joining the roofs is too expensive. Can someone give me an example of what the additional percentage might be? Thank you

In General questions | Asked By Anne Lee | Jul 7 14
1 Answer

Fully applied membrane substitute

When applying exterior insulation, the PERSIST method specs a fully adhered membrane covering the sheathing to control air, moisture and water. These self adhered membranes can be costly, so I'm wondering if there is any risk in using the peel and stick membrane where it's needed and then less expensive draining type house wrap in the field of the wall.

This might be trickier to install but right now I'm just interested in the performance of these materials - would it matter that the house is wrapped in 2 materials with very different perm ratings?


In Green products and materials | Asked By Mark Fredericks | Jul 8 14
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