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13 Answers

Condensation on windows

I am a HERS rater, back in the summer, i tested a house for a builder.
built about a year ago and lived in.
​they​ had a problem with condensation ​collecting​ on windows
windows face north, and air changes in house were 2.4ACH
they had one continuous fan that was not working
so they replaced this fan which is guest bath, off kitchen, near laundry.
this now is supposed to run at 60 cfm continuous.
They replaced a second fan in the master bath to run continuous at 50,
occupied at 100cfm. ​both on the main floor, there is no second floor,
but a finished walk out basement.

In Energy efficiency and durability | Asked By Dwayne Petko | Nov 17 17
11 Answers

Does Anyone NOT recommend using Zip R3 in CZ 4 (Northern Virginia)?

We are working with an architect to design a practical and cost-effective 'energy-smart' located Fairfax County, VA (outside Washington, DC). I am not an architect, engineer, or building scientist, so trying to decide on a practical, energy efficient, above-code (tight envelope and higher assembly R values, but not NZER or Passive), durable, cost-effective wall assembly has proven harder than expected.

In Energy efficiency and durability | Asked By user-6777975 | Nov 13 17
5 Answers

Foil vs Bubble Foil or Foam Foil

Hi I'm insulating a shed-like structure on my property to create a comfortable living space. With regard to the tin roof I've been advised to use a layer of Bubble foil on the battens directly underneath the tin and then below that in the remaining ceiling space (above the plasterboard) Fibreglass batts. My question is: In this kind of context will bubble foil give an improved insulating performance over and above foil (sisilation) on it's own directly under the tin? i.e. Is bubble foil worthy of the added cost??

In General questions | Asked By AussieQ | Nov 15 17
6 Answers

Region 5 below grade basement insulation techniques with intention to finish

I've probably read most or all of the articles on the subject 5-6 times over, but am still left with many questions as the advice can quickly change as the circumstances do, and it's difficult to keep track of all these factors.

My goal is to finish my below grade basement in 18301 Region 5. Cape cod style home built in 1968. 954 sq ft basement.

In General questions | Asked By Ryan O'Rourke | Nov 19 17
2 Answers

In Md. I have a vapor barrier and I want to insulate and finish basement

What is the best way to finish the basement. I already paid for drainage system; vapor barrier is up on walls. What is the best type of installation...? Basement is framed 24' vs 16. This is so frustrating for me, my brother gave me R19 that he had left over but I don't think I can use it. Someone told me not to use paperback fiberglass near vapor barrier...Help!

In GBA Pro help | Asked By blgoodw | Nov 20 17
2 Answers

Carpet on concrete slab--vapor barrier?

We are working on a :budget restricted" fix-up of a house near Dayton, Ohio (Zone 5). The house is slab-on-grade with solid masonry walls (we are adding 1.5" of polyioso to the interior of them). The floor is concrete slab on grade, and has had asbestos and then vinyl tiles applied to it in the past, and most recently had carpet over this. When I tore out the old carpet it was quite filthy, but I can't say I saw any visible mold, etc. on the surface or backing.
Approximately 75% of the slab is covered with these tiles, and the rest has various amounts of mastic or glue.

In General questions | Asked By Mark Waldron | Nov 20 17
2 Answers

Attic fan for ventilation in winter?

I have ice buildup because of heat escaping and melting snow and causing ice buildup on my gutters. I have vented gables on both ends of my attic in a split foyer home. Can I install of ventilation fan and set the temperature at say 40 degrees to move that warmer air out and avoid the ice buildup??
Any advice is greatly appreciated... Mike F

In Energy efficiency and durability | Asked By Feiks | Nov 20 17
11 Answers

Sizing a ductless minisplit for heating

Hi all,

I'm going to install a ductless heat pump. I settled on LG Art Cool Premier (HYV1 or HYV2). Now I need to figure out system size, and there is too much info.

I have 550 sf addition built in late '80s, which is a split lever open space, and is VERY cold (i've attached some photos)!

It has a large french door (8x10' glass, 3 sections), 7 windows, and 5 skylights. All are double glass.

In General questions | Asked By Levab | Nov 16 17
1 Answer

Product thoughts

In my quest to build, I would be interested to hear any feedback or criticism around the Thermobuilt system. ( http://www.thermobuilt.com/ for reference. I am not affiliated. )

I don't really have a specific question. It's always nice to hear input from to professionals on this site revolving around products.

Green-does this use nasty blowing agents? The product appears to be type 1 EPS. Good product? Something worthy?

In Green products and materials | Asked By Drew Baden | Nov 20 17
5 Answers

Which gas furnaces are most efficient in their use of electricity?

I am about to replace a 13 year old 120,000BTU furnace with a much smaller unit that will be less noisy.

I understand that the fans of these units are a significant power draw. The state of MA will give the same rebate to all 95%AFUE furnaces. Is there a difference, where some brands of 95% AFUE furnace will actually use a lot less power?

FYI my furnace is in the attic so I will end up putting in a horizontal downflow unit.

In Energy efficiency and durability | Asked By rich cowen | Nov 16 17
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