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23 Answers

Basement subfloor retrofit insulation options

We recently renovated our 1897 brick workman’s cottage here in Chicago. We’ve done our best to upgrade the energy efficiency of it including insulation upgrades– although based on some of threads, may have made a few not optimal decisions (closed cell soy foam interior – we’re in an historic district so we cannot make any changes to the exterior.). We’re now seeking to tackle our basement floor, specifically insulate it.

In Energy efficiency and durability | Asked By brandon antoniewicz | Nov 30 10
0 Answers

How to insulate a workshop?

Planning on having a 60’ (L) x 30’ (W) x 12’ (H) post and frame (pole building), built in climate zone 5B. The building will be bisected by a 2x6 interior wall so that 36’ x 30’ will be used as an un-insulated garage and the remaining 24’ x 30’ will serve as an insulated and conditioned workshop. The floor will be 4” concrete slab on grade poured after the building is erected. Exterior walls are metal panels mounted to wall girts and the roof is also metal on engineered trusses.

In General questions | Asked By Ken Hodge | Aug 23 16
0 Answers

Ceiling Fan Efficiency w/ 25' Ceiling

We are in the process of building a house with 12' sidewalls and a vaulted ceiling. The ceiling height from the floor will be about 24'. The area below this fan will be 728 sq. ft. A local salesperson stated that a ceiling fan (in a vaulted application) will not adequately move air even with a 72" down rod. We were going to purchase a 68" diameter fan. I do not feel the person in the retail position may be giving the correct information. Any assistance would be greatly appreciated.

In General questions | Asked By Jeff Larson | Aug 23 16
1 Answer

Flexible, Long Lasting, Sealant

In upper CZ-4, I will be placing Huber Zip R-6 panels ( with 1" of PolyIso on the interior) against 2x6 stud walls and plates. I would like to use a sealant between the PolyIso and the bottom & top plates and around the windows and doors. A Huber rep recommended the use of a Silicone Sealant or a urethane based sealant. An article that I read recently, "Making sense of caulks and sealants" indicates that silicone does not adhere well to wood.

Would you please recommend a sealant that adheres well, remains flexible forever, forms an airtight seal and of course is economical.

In Energy efficiency and durability | Asked By Ted Cummings | Aug 23 16
7 Answers

Help me understand static pressure in ducted minisplit systems

Hi all,

Tried to piggyback a comment on this thread (http://www.greenbuildingadvisor.com/comment/reply/55726), but I guess the thread is too old and my comment was marked as spam.

I am planning a ducted mini split for the 2nd floor of our home. I have run manual J calculations and find that a Fujitsu 9RLFCD will fit the heat/cool load, assuming I can distribute the BTUs to all the rooms.

In Green building techniques | Asked By Clay Whitenack | Aug 16 16
2 Answers

It is better to spray closed cell insulation on back of roof decking or over the ceiling joists?

New construction with cathedral roof.

In Energy efficiency and durability | Asked By Cynthia Richards | Aug 23 16
1 Answer

Should closed spray foam be used in Cathedral vented roof?

We paid for spray foam, now the builder is saying there's no need to spray as high in the cathedral roof, it would be more efficient to sheet rock near the HVAC and spray foam. After reading articles it says it's best to spray un-vented cathedral roof, which will keep bad heat and air from entering at the surface, therefore the area between the HVAC and cathedral roof is cooler.

In General questions | Asked By Cynthia Richards | Aug 23 16
1 Answer

Difference between Cardinal Glass factory-sealed units vs. third-party sealed units

After researching several window manufacturers I learned some manufacturers buy sealed glass units directly from Cardinal and others only buy the raw glass sheets from Cardinal and seal them in house or sub out the glazing to a third party manufacturer.

Is there any benefit to go with a manufacturer that only buys their sealed units directly from Cardinal?

I assume window manufacturers save money sealing and filling the units in house but do they have the same quality controls in place like Cardinal Glass seems to have.

In Energy efficiency and durability | Asked By Steven Johnson | Aug 22 16
3 Answers

Questions on creating a conditioned attic

I've been reading through the other questions and articles by Martin and I think I have something of a handle on my options, but I really feel like I need some expert advice before I proceed. I'm in a suburb of Chicago (Zone 5a) and just bought a house with a attic that was basically built as a 3rd floor complete with a set of stairs coming up to it. It has 8" rafters and is currently vented. As it is, it's pretty hot in the summer, easily over 120 degrees. The floor of the attic is insulated and has plywood over it so the current thermal envelope is to the ceiling of the 2nd floor.

In Energy efficiency and durability | Asked By John Daves | Aug 22 16
8 Answers

Insulating rim joists

Hello. I've been reading q&a on this website for a long time and have always found the content very helpful. This is my first time posting a question and hope someone has some information for me.

In General questions | Asked By P Coyne | Aug 18 16
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