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9 Answers

Minisplit or furnace?

Hi, I know there is lots of discussion about this; however, our proposed new construction seems to be in unclear realm of which to use.

Asked By Mark Buckingham | Aug 28 15
12 Answers

Alpen vs Inline

Hello,

I am comparing Alpen and Inline products. I have recieved quotations from both companies and I would like to pose a few questions to those that have a little more experience in this relam.

Both companies use fiberglass frames and Cardinal Low E Glass. Inline makes their frame and Alpen purchases the frame material through Inline.

Alpen makes a double pane window, their 525-s Series, that have a whole window U-factor of .19 for casements and .15 for pictures. Inline offers a triple pane window with a whole window u-factor of .17 for a casement and .14 for a picture.

Asked By David Mosijchuk | Mar 25 15
0 Answers

Thirdparty filters for zehnder hrv/erv units?

Besides ordering from zehnder, are there any other filters available that will fit their units? It's not a question of price but more so of long term availability. If they go out of business will I still be able to source filters? I haven't had the chance to pull one out of the packaging and go down to the local HVAC supply house with a tale measure.

I'm an electrician and not an HVAC contractor so I don't understand if these are a common size/shape/build or totally proprietary.

Asked By Lance C | Aug 29 15
4 Answers

Rim joist foam and termites

I'm not sure if this would fit better 'Energy Efficiency and Durability' category, but I have a few questions about using foam to insulate rim joists. From an air-sealing and thermal performance perspective foam seems the clear choice. I've read Martin's FHB article and spray foam and cut-and-cobble approaches make sense.

Asked By Jeffrey S | Aug 24 15
0 Answers

CMU walls and rigid foam

Retrofit concrete block walls painted inside and out. Exterior foam then rainscreen then siding. Keeping painte d block as interior walls.
Do I have to be concerned with the vapor permanence of the foam.
Also, would there be any benefit in using foil faced...other than r value.
Southern Georgia coast.

Asked By Robert Brown | Aug 29 15
9 Answers

Retrofit / renovation to bring heating costs under control

Hi folks,

Thanks for creating this great resource for newbies like me to learn!

We're actually near Toronto, Canada, but I think you could consider us Zone 6A for your purposes. We bought our ~2000 ft^2 1981 home last year and suffered a horribly cold and expensive winter, so we'd like to take steps to bring that back in control.

Asked By Justin Allport | Aug 20 15
6 Answers

Insulate cold water pipes

Replaced galvanized pipes wth copper about 15 years ago.
Current hot weather in California causes extreme heat in attic despite solar attic fan and gable vents.
Cold water in pipe line is extremely warm and warm water is now in toilets
Fear warm water may crack toilet tanks and ruin flooring.
How best to insulate these cold water pipes from water getting warm?
Company which did insulation spoke of 3" wall around these pipes.
Can you explain what this is and best way to insulate these pipes?
Thank
Paul

Asked By Paul Deleon | Aug 28 15
13 Answers

How to build a gabled roof on a rigid insulation roof?

Hello to all at this forum. Back in 2013 I posted on my garage build here....

http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...

Since a few months now I had started doing some work on my home to increase the insulation value.

I am including a photo of how it is today just before we add the roof sheathing, but I am sort of stuck on how to include a gable roof on each end of the house.

Asked By Leon Stepanian | Aug 17 15
19 Answers

Skipping radiant floor heat in a passive house?

I'm building a house with (conservative numbers) R 60 walls and R90 ceiling. The windows are in-swing casements with double seals. The floor is going to be stained concrete on 2" insulation. I had 2 consultants tell me that I will not need radiant floor heat it will be too much. We will have a whole house air circulation system and a gas fire place. I am worried about not putting in the pipes in the floor and then being wrong. I am considering just putting in the heated floor under the rooms away from the fire place. I could add a heater to my whole house ventilation system if needed.

Asked By Jenz Yoder | Aug 25 15
4 Answers

Unvented Roof, 3B, Foam-Free

Hi Martin,

First off, I have read a wealth of articles on the subject of unvented roofs, by yourself and Joseph Lstiburek. I started with your “How to Build A Cathedral Ceiling” article and read pretty much everything related to this from you and Lstiburek. The conclusion being that for an unvented roof you either install closed-cell spray foam between the rafters, or rigid foam above the sheathing at a thickness dictated by your climate zone to keep the sheathing warm enough.

Asked By Joe G | Aug 26 15
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