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20 Answers

Heating and ventilating a very small space

My wife and I will soon be building a 250 square-foot in-law unit in our backyard in the Bay Area in California. The unit will have a bathroom and a great room with kitchenette and living space. It'll be built on a slab with advanced framing and sealed as well as we can. It'll have a gable roof and a cathedral ceiling.

We were originally planning to heat the space using a radiant floor system and ventilate with a standard bathroom exhaust and range hood, but after reading articles on this website, I'm not sure that'd be the most effective solution.

In General questions | Asked By Nick Jensen | Aug 4 12
4 Answers

Zinc Roofing Run-off

We are building a boathouse and considering a zinc standing seam roof. Because the run-off will be deposited directly into a lake, I'm researching levels of contamination that find their way into run-off from different roofing materials. Untreated galvanized steel is obviously out of the question, but I am getting mixed reviews on zinc - does anyone know whether run-off from a zinc roof would be more detrimental than from a painted steel roof?

In Green products and materials | Asked By wendy wisbrun | Aug 7 12
9 Answers

Solar radiant

Has anyone on the site tried to do solar radiant heating with a collector and pex in zone 6? I'm trying to avoid using propane in the house and I'm wondering how/if radiant solar works in a cold climate. I just need some supplemental heat for my wood stove and electric baseboards..

In General questions | Asked By stephen edge | Aug 5 12
3 Answers

Rigid foam 2' below grade? Zone 6, Central Colorado

Long time listener, first time advisor punching bag.....

In Energy efficiency and durability | Asked By Greg Follet | Aug 6 12
10 Answers

Reuse SIP polystyrene cores

I am building my home and ordered SIPs for the roof and walls. This was 3 years ago! We fell short on funds and the home remained untouched during this time, until we were able to rebuild our bank account. During this time the panels suffered moisture damage (replaced the tarps that covered them 3 times even!) and we were not able to use them. We continued with stick framing instead. We were left with all these panels laying around, so we stripped the rotten OSB leaving just the polystyrene cores. All the moisture was removed and they were put in storage.

In General questions | Asked By Neo Na | Aug 6 12
5 Answers

Raised concrete slab?

My wife and I just purchased a moderately sloping lot in northern Arizona, near Flagstaff and we're in the initial stages of designing a roughly 1000 sq. ft. home. Due to it's 6000+ft elevation the area can get significant snowfall in the winter. Since the lot is downslope from National Forest land we have concerns about drainage thru the soil, particularly with spring snowmelt.

In General questions | Asked By karl ludwig | Aug 5 12
2 Answers

Insulate Supply Line in Attic?

Hi, I'm trying to get a little more efficiency out of my HVAC system and I'm wondering whether to bother with attempting to insulate some supply lines that are in the attic of a commercial building. The attic is within the thermal envelope but it is unconditioned. The attic is used for storage and therefore has a floor. All the supply lines have been mounted flush on top of the floor and I can feel major air leaks at all the seams/connections. My idea is try to slightly lift sections and apply mastic tape to the seams on the bottom as well as apply mastic to the sides and top.

In Mechanicals | Asked By Kevin Dorsey | Aug 6 12
7 Answers

I Used the Wrong Nails

I am framing a first floor deck and I used the wrong nails. I shot 2" x 0.99 ring nails instead of 2 1/2" common. The floor is 11 7/8" I-Joist with 3/4" Pinnacle sub-floor. I applied plenty of construction adhesive and only attached the sub-floor only one sheet ahead of the adhesive application. My nailing pattern is about 4" to 6" along the perimeter and 6" to 8" in the field. Should I go over it with the correct nails?

In Building Code Questions | Asked By John McCormack | Aug 4 12
2 Answers

Humidity in Basement

Last year we added an addition onto our house located in Nova Scotia on the Bay of Fundy.The foundation is ICF and the header spaces are insulated with spray foam. There is drainage tile around the outside of the foundation. The problem - I'm getting around 4gal of water a day from my dehumidifier in the crawl space! (unheated). The floor of the crawl space is earth/sand/PLASTIC/Sand. There is no standing water and no signs of leakage but the top layer of sand is wet in some areas. There is no ventilation in the crawl space. Any ideas on how I can remedy this?

In General questions | Asked By Chris Harwood | Aug 4 12
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