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3 Answers

Should I do a birdsmouth cut for low sloped (tiny house) shed roof?


We're getting close to framing my roof for my tiny house on wheels. The roof is a low sloped 2:12 pitch. There will only be 3-6 inch eave/overhang.

Should I do a birdsmouth cut for this? What benefits does this provide? If not, what method do you recommend that I do and why?


In Green building techniques | Asked By Grey Wolf | May 25 17
2 Answers

New home in DE

Plan to sheath with insulated ZIP 4x8 panels. In the interior looking at the 2x6 stud caviity should I caulk the Zip insulation to the stud or is there enough pressure from nails to seal same?



In Energy efficiency and durability | Asked By Edward Serafin | May 25 17
9 Answers

Average lighting, appliance and plug loads for PV sizing?

In doing some energy modelling for a future single-family net zero residence (in Canada), I am running into the problem of trying to guesstimate what the total lighting, appliance and plug loads will be. Because it can be different with every specific family, I'm wondering if anybody has any links or resources they can provide that offer average values for these loads that one can use. I will calculate the heating, cooling and hot water loads separately, but am hoping somebody has some suggestions for those remainders.

In Mechanicals | Asked By Burke Stoller | May 23 17
4 Answers

Calculating annual heating losses

I'm trying to determine cost effectiveness and payback periods for going with thicker insulation on the house I am planning. My project manager does not offer services of energy modeling, so I would like to do some of it myself. I will probably end up paying an architect for it, but I'd like to give it a go myself.

I calculated U-values for several walls, floors, roofs and windows. I have areas. I have heating degree hour value for my climate, which is ~78 000 (typical central europe). i have insulation prices.

It's extremely straightforward.

In Energy efficiency and durability | Asked By Davor Radman | May 24 17
9 Answers

Trane 38 SEER 15 HSPF minisplit

Anyone know anything about this, especially its output in low temps. Claims to provide heat down to -22F and cooling to 129F.


In Energy efficiency and durability | Asked By Venkat Y | May 24 17
3 Answers

Use foam board underneath fountain footer?

I am installing this fountain in PA:


I don't want to dig 36 inches to the frostline.

Can I dig 2 feet, put tamped 3/4 clean stone, place XPS foamboard and then pour concrete?

In Green building techniques | Asked By John Sean | May 22 17
18 Answers

Adding ridge vent and continuous eaves sensible for vaulted ceiling?


In Green building techniques | Asked By user-6793320 | Apr 5 17
3 Answers

Insulating a shed roof addition from the 60s

Hello Folks:

In General questions | Asked By Josh Dudeck | May 24 17
5 Answers

Heat loss calculation for a ductless system

I did a thorough whole house heat loss calculation for my project when I was considering doing radiant floor heat but I have now decided to go with a Ductless Mini Split system. On one of the final tables of my spreadsheet (where I calculate design day requirements), I seem to have put in a "Boiler Efficiency" factor most likely for the heat source for the water for the hydronics. When it comes to sizing the outdoor units, should I leave that final adjustment? I attached a picture of the table showing the data.

In Energy efficiency and durability | Asked By John Brown | May 24 17
1 Answer

home in DE

Sorry the word was stud. I am addressing the interior stud cavity.

Thanks Ed

In Energy efficiency and durability | Asked By Edward Serafin | May 24 17
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