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16 Answers

We are building a straw-bale house with steel bones in Sacramento, CA in spring 2015 and I'd love to get some insights from the community! We are pretty far along into the design process, but with nothing purchased as of yet I'd love to get some input before we put our money where our mouths are.

Our goal is to have a (mostly) passively heated and cooled home in (relativity) temperate Sacramento, CA. Passivhaus would be nice but it's an aspiration rather than a goal. Our lot has a number of trees for shade that we plan to utilize, especially in the western aspect.

Asked By Nick Campbell | Aug 26 14
10 Answers

I'm in zone 4 (NYC suburb) and the original house is a 2 1/2 story wood framed house heated by gas fired one pipe steam. Cooling is from window units. Our addition (currently rough framed and dryed in) is two stories with an 18' x 15' exterior footprint. 3 foot block stem walls make the lower level slightly smaller than the upper. The upper level, which connects to our main floor, will be our new kitchen, and the lower level, which connects to a walkout basement, will be a play/TV room.

Asked By mike mcguirk | Aug 25 14
3 Answers

I am in the process of trying to determine how much strapping spacing is needed on a ceiling to support 22" of blown-in cellulose above it. The strapping is 1x4 pine and I plan on spacing 16" OC whixh makes the space between supports of 12". The strapping is holding 6 mil poly up against the bottom chord of the truss. There will be some ballooning of poly downward in those squares between truss and strapping. 5/8" Sheetrock will be used up against strapping to finish. Thanks in advance.

Asked By Matthew Michaud | Aug 26 14
13 Answers

I would like to ask the math pros here on how to calculate heat loss from infiltration rates.

I have seen so many different formulas in the last weeks that my head is hurting.

So would like to have a "reliable" formula that could be used in my never-ending expanding excel spreadsheets !

Something with at least a little bit of proven precision, that could be used to effectively get additional heat loss using door blower results or planned target value.

Links or straight formula please :)

Asked By Jin Kazama | Aug 25 14
1 Answer

Hi all,

New owner of a 1 1/2 level cape here. Finished upstairs. Zone 5. I'm experienced with home renovations and DIY, but new to Capes.

Trying to bring upstairs environmentals in line with lower level conditioned home temps year round without running the mechanicals 24 /7.

No insulation to speak of. No ventilation. No vapor barrier. Planning to make the attic "outside space".

I've blocked all of the underfloor joist bays, sealed all chases and penetrations, insulated the kneewall hatches very well, etc. This has helped a lot.

Next steps:

Asked By M Welch | Aug 27 14
2 Answers

We have a 1950s house in Saskatoon, SK, Canada (climate = warm summers, very cold winters and ~ 350mm moisture/year). Our neighbours re-built their house and the landscaped surface is now ~12" higher than ours (about level with our stucco siding). One of their downspouts also drains directly onto our property (don't ask). There is 3 ft between our outside wall and the property line. They have a concrete sidewalk between their house and the property line.

We have had several suggestions for dealing with drainage on our side:

Asked By Colin Kindrachuk | Aug 27 14
2 Answers

This is something that as passed a few times in my background brain processes,

How does SHG on exterior cladding/glass influence heatloss ??

If glazings specs 50%VT , a part of the remaining 50% must be converted to heat?

If exterior cladding on a building is black, and sun is shinning on the south face,
it must affect the heatloss greatly for the shined on walls ??

As an example, let's assume a building up here cold north.
20c inside 0c outside.
Sun shines on a large flat south wall that was cladded with a black painted steel sheets finish.

Asked By Jin Kazama | Aug 28 14
30 Answers

My house has high levels of CO2 / carbon dioxide, every room is between 1100 ppm to 1200 ppm according to an air quality test I had. There are only 2 grown occupants and it's a 1000 sq. ft. brick house. No pets or plants, gas stove / furnace / water heater.

The basement was the only area that had between 900-1,000 ppm of CO2. I've read ASHRAE likes to see under 1000 ppm of CO2. We do have headaches & drowsiness but aren't sure if it's strictly from CO2. For reference, our CO (carbon monoxide) numbers were all under 2 ppm.

Asked By Jeff Watson | Mar 9 14
9 Answers

I would like to decide on putting in solar panels to reduce energy costs.

I have read about the next generation solar panels not being to far off.

Question: Would it be better to install current solar panels or wait for the new type that will be coming shortly?

Asked By John Alberti | Aug 26 14
2 Answers

I recently installed this model Zehnder HRV, and now need to learn how to balance it. The manufacturer's installer manual is too brief on this procedure to be helpful. Is there anyone out there who can anyone give me the detailed procedure on how to balance this HRV?

My main concern is to ensure the intake/exhaust is balanced and that I am not pushing too many CFM's into/out of the house. I don't care too much about getting each room's cfm perfect at this point - since I'm going to be continuing to renovate the house. I just don't want to be pushing moisture into the walls right now.

Asked By Matthew Robinson | Aug 27 14
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