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9 Answers

Does my house need to breathe?

We're building a house in the Southeast and want to try for the tightest shell possible. During the interview process several contractors keep telling us the house can be tight but needs to be breathable. Is there any science to this or are they just stuck in their ways? We're planning on using some kind of air exchange system. Thank you kindly!

In Green building techniques | Asked By megan wood | Jan 1 15
11 Answers

Better option than a heat-pump water heater for a boiler?

I have a home in Zone 4b that currently uses propane (no natural gas service available) to fuel a 10 year old mediocre boiler (hydronic baseboards) and mediocre tank water heater, both in the garage. I'm considering replacing both the boiler and water heater with two electric heat pump water heaters (2.5 to 2.75 EF) and wonder if there are better options I haven't considered. Heat pump mini splits and a wood stove currently handle part of the heat load, but don't take care of the whole house. PV is scheduled to be installed soon and will handle the total load for these units.

In Mechanicals | Asked By Jane Whitmire | Dec 31 14
5 Answers

Insulating around crawl space vent


I have an older home in Seattle where the temp is only below freezing a handful of days a year. Vented craw spaces are the norm in order to deal with constant ground moisture. Crawl space vents were added to this house by cutting into the rim joist. The joist cavities next to these vents lack any insulation/batting for roughly 4 ft. I am wondering if it is worth it (or against code) to use foam board between these joists to help insulate.


In General questions | Asked By Michael Mason | Jan 2 15
3 Answers

Rigid insulation outside of ZIP R ?

Apparently my original plan to put polyiso on the outside of ZIP R isn’t recommended by Huber.



No. An additional layer of exterior foam on top of ZIP System R-Sheathing is currently not recommended.”

My brain fart to install steel strap storm/racking bracing on the wall, then 1” polyiso over the studs, then ZIP R didn’t get the nod from the engineer.

Thought, suggestions ?


In Green building techniques | Asked By Roy Goodwin | Jan 3 15
3 Answers

Asking for advice from off-gridders about the recent blog "Solar thermal is really really dead".

A recent blog by Martin Holliday has me rethinking our approach to our Super insulated off grid retirement home. I'm not going to rehash the blog but I'm wondering how people who specifically live off grid view the opinions in it. I've spent enough time living in off-grid situations to know that the math about our mechanical systems is different when there is no energy "bank" to go back to when you're short.

In Mechanicals | Asked By Geoff Frood | Jan 2 15
1 Answer

What to use on a concrete floor in finishing a walk-out basement?

I recently purchase a condo that had a walk-out basement space ready for finishing--cement half walls on 2 sides, studded wall on another and all concrete wall on the third. The studs were installed and fiberglass batts installed in rim joists and between studs with a plastic barrier over the wall surfaces. I live in Michigan (Zone 5). As I prepared to finish the basement and did lots of research here, also discovered leaks and cracks in the foundation walls--since repaired.

In Energy efficiency and durability | Asked By Phylis Floyd | Jan 3 15
1 Answer

Should gas furnace registers be left open or closed when using a wood stove?

We have a gas furnace (fueled by propane), but because it's too expensive to operate we purchased a wood stove insert. This is not only cheaper but does heat the entire 1900 square foot house.

My question is: Do we leave the gas vents (registers) open or closed when operating the wood stove (which is 95% of the time)?

In Energy efficiency and durability | Asked By Mary Kloman | Jan 3 15
126 Answers

What is the greenest and best material to use for indoor plumbing?

I read that PEX and copper are not the best. Then if PVC is used to bring city water to my home, does that contribute to any chemical leakage? Should I make my plumbing out of natural materials?

What is the best and for how long will it last?

In Green products and materials | Asked By J FARNOCCHIA | Nov 1 14
3 Answers

What's a good source for historical temperature data?

What's a good place to get historical temperature data for a relatively long period, say 10 years or more? This is for the Seattle, WA area. Ideally this would be impeccable data that no one would argue with.

In General questions | Asked By David Meiland | Jan 2 15
3 Answers

Should I install insulation?

My house in LA is about 100 years old and there is no insulation within exterior stucco walls.

I'm debating whether I should install insulation (these pink sheets sold in home depot) since I have a chance to do so.

The stucco looks pretty thin to me. If rain water gets into these pink materials, would it cause fungus growth or maybe bugs build a nest within? A house has its own working built in ventilation and functioning mechanism for 100 years. Maybe I should not disturb it.

In General questions | Asked By liz lee | Jan 2 15
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