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10 Answers

Roof construction for low-slope roof


Asked By Kevin Hoene | Sep 21 15
6 Answers

How to release stored heat in floor's thermal mass

Years in the planning, five months in building, we are now home at last in our 1,100 sq passive home at 46 degrees North in North Central Minnesota.

Fujitsu Halcyon mini split heating and cooling.Heat load is around 26K BTU

Q 1. Am I correct assuming that I have to set the the two mini splits' thermostats at a night time temp that is lower than indoor temp before the concerete floor's thermal mass will release its heat?

Last night I set mini splits at 66 degrees -- guessing that that setting would be cooler than floor.

Asked By Randy Bunney | Oct 2 15
6 Answers

Outdoor reset vs setback on single-stage boiler

I'm trying to figure out what would be the more efficient thing to do in my situation. I've recently heavily insulated the house and installed a radiant hydronic system (making sure to do a detailed load analysis and system design by the Sigenthauler hyrdonic book). While the radiant system and boiler loop are new, the boiler is a 20 year old cast-iron boiler that I want to nurse along for a few more years (mostly because of current budget).

Asked By Eric Stormfield | Oct 3 15
0 Answers

Any one have experience with Chilltrix equipment?

A client has asked me to evaluation Chilltrix HVAC systems:http://www.chiltrix.com/small-chiller-home.html.

It appears to be an inverter driven mini split style system that uses a chiller rather than a condenser. I am assuming that it uses and expels significant amounts of water as it does not use a refrigerant, but their documentation is not very specific.

Any feedback would be appreciated.

Asked By Carl Seville, GBA Advisor | Oct 4 15
1 Answer

Can I put Roxul over sheetrock? On the interior

I was planning on creating a built in window seat/bed in a bonus room over the garage. We just purchased the house and I am guessing It's likely one of the coldest parts of the house in the winter. It's just above the garage doors. Likely has little insulation in the floor, vaulted ceiling so probably R13 at best. The house was built in 1991 +/-. I am toying with the idea of furring out and insulating with some roxul boards around the window and vaulted ceiling area. I was going to just put it right on top of the sheet rock and cover it up with bead board or something similar.

Asked By Andrew Bennett | Oct 3 15
2 Answers

Radiant heat and spray foam insulation

I have just installed radiant heat under my deck that is now part of our living space. The area is 24 ft by 6 ft by 6 in and 2 ft of the ground. The pex tubing is attached directly to the deck with alum. heat
transfer plates with a 6 in space from the outside edges. My question is: can I spray foam over the
pex and plates without any airspace at all ?

Thank you

Asked By Anthony Bartolotti | Oct 3 15
6 Answers

Cut and Cobble


This is a follow up to my original post seen here:


Getting ready to begin this ceiling insulation project using the "cut-and-cobble" method. I have a few more questions.
1. would it be better to use XPS product or something like R-Tech?
2. I will be using can spray foam for the gaps, but how do we attach to underside of the roof sheathing?

Asked By Rob Henderson | Oct 3 15
0 Answers

Attic Kneewall Insulation

I have a raised heel truss system. The contractor installed wall sheathing up to the bottom of the truss 2x4 as shown in attachments. My overhang is 2' so I will have ~2' of soffit. I will vent according to the sq. footage of my ridge vent (hip roof). I am wondering if it is best to leave these gaps alone, at 3.5" tall or if I should put scraps up and make them closer to 2" tall, or if I should block the ones that will not line up with the vented soffit locations completely.


Asked By Nicholas C | Oct 3 15
1 Answer

Factors That Counter Individuals From Starting An Internet Business

Before any company are created and anything be made, there should be a notion. Entrepreneur ideas would be the bread and butter to perform anything in the industry world.

Asked By Maude Yoo | Oct 3 15
13 Answers

Ideal window rough opening gap for good air sealing

The manufacturer I'm ordering windows from allows a rough opening gap around the window of 3/8" to 1/2" from all 4 sides (so the rough opening would be 3/4" to 1" wider & taller than the window).

Asked By Nick Hall | Sep 28 15
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