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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?

Asked By John Sean | May 22 17
18 Answers
3 Answers

Insulating a shed roof addition from the 60s

Hello Folks:

Asked By Josh Dudeck | May 24 17
6 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.

Asked By Burke Stoller | May 23 17
7 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.


Asked By Venkat Y | 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.

Asked By John Brown | May 24 17
3 Answers

Building new home in Delaware and using insulated Zip exterior sheathing

Addressing the stud cavities, should I tape or caulk zip insulation to studs or is the compressed sheathing insulation to stub enough.

Asked By Edward Serafin | May 24 17
1 Answer

home in DE

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

Thanks Ed

Asked By Edward Serafin | May 24 17
7 Answers

Kerf channel and thermal bridge

I am working through a shed roof design for a small shop and I have always liked protruding rafter tails. Obviously, I know these days they have been entirely eliminated due to the thermal bridging.

I will ask one question though and show a couple drawings. What if one were to cut a deep enough channel or kerf (may not be the right term) along the exterior face of the envelope (in my case, a SIP)? And then, if that channel (all the way around BTW) were filled with a foam of some kind.

Asked By John Brown | May 20 17
2 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.

Asked By Davor Radman | May 24 17
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