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4 Answers

Is there any way around putting a heat source in every bedroom?

I was speaking with an HVAC guy in my area today who reminded me that code says we have to have a heat source in every bedroom. We're planning on putting a single head ductless minisplit in our 1450 sf high performance home (to be built next year). Are there other exceptions/solutions out there, or do I just stick a Cadet heater in every bedroom and disconnect them after the inspector checks it off his list?

In Building Code Questions | Asked By Alyssa Hoyt | Feb 4 16
12 Answers

Geothermal Quote question

I am building a new home this Spring and I plan on having ground sourced geothermal. I received a quote from one contractor in my area. His plan is to do a 6 ton horizontal slinky loop field with a 4 ton heatpump. He claims that an oversized slinky loop field performs the best, however I've heard bad things about the slinky loops, and slinky is the only kind of loop they do.

It doesn't seem efficient or cost effective to overbuild the field since that is a major cost. Does anyone have experience with this?

In General questions | Asked By Jordan Garrow | Feb 3 16
2 Answers

Blown Insulation

Hello, we have a bonus room over the garage that does not have an attic. The ceiling of the bonus room is drywall, studs, then roof. The ceiling goes to an angle, then across to the other angle to create a ceiling that looks like the letter "A". I took out the middle line of the "A" and noticed the insulation had been tamped down by a previous owner's rodent problem. I am wanting to blow in insulation between the ceiling and the roof in between the studs, but I am not sure if I will have a moisture problem. Is blown in insulation the way to go?

In Building Code Questions | Asked By John Roy | Feb 4 16
3 Answers

Siding house in Maine

I am stripping and resideing my house I was looking at a product called prodex insulation it says it works as a vapor barrier as well as a high r-value what do you think of this type of product thanks

In Energy efficiency and durability | Asked By David Bernard | Feb 4 16
5 Answers

Wall assembly

I am not sure this is the correct place to ask this question but here it is. I am building a new home in NW Wyoming. I will have a sealed and conditions crawlspace under half the house. I have installed a radon system. The crawlspace has a poly sheet under a rat slab. The hvac is located in the crawlspace. Would it be a good idea to have the returns for the bedrooms and baths to vent into this crawlspace. It will also be insulated on the walls internally with rigid foam.

In Mechanicals | Asked By Charles Cloud | Jan 29 16
31 Answers

Which Weather Resistive Barrier behind new masonry?

I'm coming up on a project involving cladding Structural Insulated Panels (SIPs) with a full-thickness veneer natural stone wall. So, from the outside in, it will be stone - 1" gap - WRB - 6.5" SIP panel.

Question: Which WRB is preferable?
Context: I am in northwest Ohio.

The following page on this site's Product Guide lists a number of products, but links only to manufacturers' info: http://www.greenbuildingadvisor.com/product-guide/cat/water-resistive-ba...

In Green products and materials | Asked By Andy Chappell-Dick | Jun 11 13
10 Answers

Blower Door Results -- room for improvement?


I had a blower door test performed as well as thermal imaging taken.

My home is 3300 sq ft of finished living space, 1600 sq ft of unconditioned basement and about 1200 sq feet of unconditioned attic (the remaining roof is cathedral ceiling).

My blower door test came back at 3050 cfm. The tech said that to get down to 2350 cfm would be "perfect" and that I was about 30% above optimal but that it, in his estimation, we were at the point of diminishing returns outside of caulking some areas we identified as leakage sites.

In Energy efficiency and durability | Asked By Justin Brown | Feb 2 16
3 Answers

open cell or closed cell

I have a pole barn that is covered in metal . It has a cement floor,insulated garage door,it will be a/c only ,an its in central fla. One contractor wants to use closed cell at 11/2''. Number 2 guy wants to do closed cell on roof an open cell on walls [2x6]. Number three guy wants to do the entire building in open cell. I,ve read alot of info on these products, I,ve talk to guys about it an I,m still unsure. I,m leaning towards the closed cell but iI,m not sure about the thickness of it. also the closed cell is the lowest price [still pricey] I,d your thoughts on this ..

In Energy efficiency and durability | Asked By bill metzger | Feb 2 16
12 Answers

New home HRV with massive shower/hot tub and range hood

I am building a new 3500 sq/foot home in New England. Well the 3500 does not count the finished basement of another 1000 nor does it over the "attic" space. The house is being framed now and we plan on spray forming the rafters. It has zip system on the exterior sheathing & taped. So the house will be tight.
Here is my issue... the house will have a "gourmet" kitchen which translates to a 48" range with a crazy 150,000 btu cook top. If you use the standard rule of thumb if 100cfm for 1kbtu.. that is a 1500 cfm externally mounted blower for the range hood.... yea..

In Energy efficiency and durability | Asked By Ken Leach | Jan 31 16
11 Answers

Fastening strapping for steel roof

For my simple gable roof, I will be installing exposed-fastener steel roofing atop 2x4 strapping atop Grace Tri-Flex underlayment atop OSB sheathing atop trusses 24" oc. Everything I've read indicates that screws would be best for fastening the strapping, as they offer far greater withdrawal resistance than nails, but I haven't found any recommendations on the best fastening pattern. Would using two 3-1/2" exterior deck screws at each intersection between the strapping (laid broad side down) and the truss top chords be best?

In General questions | Asked By Jeff Cooper | Feb 1 16
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