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6 Answers

Do screws thru exterior insulation reduce the wall R-value

I was in a Net Zero Building class this weekend and there was mention that screws that are used to attached exterior insulation reduce the whole wall R-value by 39%.

The screws are attached from the outside thru the rainscreen, insulation, WRB, sheathing and into the framing.

This individual referred to an article from Energy Design Update (no issue was noted). I'd check but $600.00 for a subscription is too rich for my pockets.....

Any help here on the article or data at least, with other references?

Asked By brad hardie | Mar 1 15
4 Answers

Why is it so trendy to hate on radiant in-floor heat?

I recently built a 2000 square foot house in climate zone 7. The building is two stories on a slab heated by a Navien 240a combination boiler. There is no heat source on the second story, and the simple system has only one zone, which is all it needs because all the rooms in the house stay at the same temperature--maybe it's a few degrees cooler in the upstairs bedrooms if the doors are shut for 24 hours or more. I spent just over five grand on the heating system--installed--although I got a tankless water heater in the process, so the real cost was more like $3500. How is that overkill?

Asked By Josh Jipson | Mar 1 15
40 Answers

Best way to have a wood fireplace?

We are building a custom house, and are nearing our final planning stages before bids with our architect. We are planning to have a wood fireplace on the ground floor, within the building envelope. When it is burning, it will likely to burned with any glass doors on the fireplace open, for aesthetic reasons. It is only going to be used as a heat source as an occasional backup. What are the best ways to minimize the energy problems of an wood fireplace? It'll probably be a zero-clearance type of fireplace. My husband will not agree to a gas or wood stove, so don't even suggest it!

Asked By Clara Kim | Feb 22 15
3 Answers

Biggest bang for your buck?

We are about to begin construction of a new home near coastal Connecticut. We are trying to incorporate green approaches where feasible. Three main components are: Insulation; energy source (ie Geothermal); and energy distribution (ie in-floor radiant heat or forced air). Of these three green approaches, how would you rank them in terms of biggest bang for yurt buck, assuming you can't afford all three. Thanks!

Asked By Justin Murphy | Mar 1 15
13 Answers

Insulating a low-slope EPDM roof from the ceiling below

Hi. I recently had an Epdm roof installed on my 140 year old house. It's low slope and meets with a gable roof on the other part of the house. The Gable is standing seam. We had a tapered ISO board system installed as the underlayment to help with drainage and make the edge details easier to deal with. I reframed the roof and sheathed it myself before the roofing contractors started so I could save money. At the time the ceilings underneath the roof were all closed so I installed 4 inch rockwool batts right on top of the plaster/lath of the ceilings below.

Asked By joseph moore | Feb 26 15
5 Answers

Converting fiberglass+plastic basement insulation to rigid foam - worth it?

Brick/masonry house with a concrete, finished basement.

The foundation walls are insulated with R11 fiberglass, topped with plastic, and covered with drywall.

I've read vapor barriers below-grade are bad & that wet fiberglass is useless as an insulating material.

Am I overthinking the usefulness in tearing down the drywall in the basement, removing the fiberglass/plastic, and installing rigid foam boards instead?

Asked By Jeff Watson | Feb 28 15
0 Answers

Basement finish floor, slab on grade.

With the help of this site I insulated an framed my basement (90 year old house, 8-9" concrete walls). I did 2 inches of xps (eps in hindsight would have been greener but I had a deal on some xps), 2x framing with roxul r15 in between 2x. Rock is next and then floors.

Asked By Sean Cotter | Mar 1 15
1 Answer

What is the correct climate zone.

Can anyone point to a web site that will be zip code specific to determine which climate zone you are located. The Department of Energy web site leaves something to be desired. I cannot determine a clear explanation of climate zone 4 and 4 Marine. It seems there should be a site to enter zip code or address and get definitive information regarding climate zone.
Thanks,
William

Asked By william dempsey | Mar 1 15
0 Answers

pier and beam insulation under floors/house

I live in a 645 sf two story home on pier and beam. It is not well insulated, not winterized and not the most precise construction. It is about 20 years old and we just purchased it a year ago. My husband and I had plans to work on it to get it better insulated and heated, but he passed away suddenly and now I am trying to think of the things he mentioned we might try.

Asked By Jennifer Shrift | Mar 1 15
2 Answers

Trombe Wall (Non Vented) with Exterior Moveable Mode of Insulation

I am in the process of completing my energy efficient house design. Approximately 80% of the Building Envelope will be a Double Stud Wall Construction allowing for roughly 11" of Cellulose Insulation in addition to a 1" Rigid Insulation outboard of the Sheathing and inboard of the Hardie Cement Fiberboard Skin. The Remaining 20% of the Envelope will be Double Glazed Fiberglas Windows with emphasis placed on the South Elevation (Perhaps 60% on South, and 20% each on East and West). However, on the South Elevation I also have two sections of Trombe Wall - each 8' in width and 12' in height.

Asked By Thomas Tricarico | Mar 1 15
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