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7 Answers

How low is too low for indoor humidity?

So you guys have answered numerous questions about humidity for me during the summer. I have a 20 year old two story house that we bought this year and promptly bought two new HVAC 5 ton units and put open cell foam in the attic and encapsulated and foamed the crawlspace. The attic has a couple of supply vents and the crawl has four supply vents and a return. My question is about the low humidity I am now getting now that it is finally getting cold in Nashville.

In Energy efficiency and durability | Asked By John Sexton | Nov 20 16
3 Answers

Is it worth it to add more attic insulation on top of R-40?

My house was built in 1989, the attic originally had fiberglass batts with loose fill rock wool. A couple of years ago cellulose was added to bring the overall R value to about 40 (hard to calculate exactly because the weight of cellulose also compressed whatever that's beneath it). Now with $300 I can add 4 more inches of cellulose to bring it to about R50. Is it worth the cost?

In General questions | Asked By Joe Blanco | Nov 20 16
13 Answers

Insulation on exterior and interior

My house was built in 2009 in climate zone 6. It has a poured concrete foundation with R-5 XPS exterior insulation. Currently there is no insulation on the inside.

I am planning on finishing my basement and am curious on what the best way to insulate the interior would be. I spoke with my city inspection department and got some conflicting information on energy code compliance. One inspector advised not to add any additional insulation and the other advised 1"XPS with a 2x4 uninsulated studwall was sufficient but the XPS was not totally necessary.

In Building Code Questions | Asked By Nick Collins | Nov 14 16
2 Answers

I need advice about a new central heating system

I have to replace our central heating system within the next year or so. We live in a gas-heated wood-framed 3-story colonial with 4 zones, built in 1987 in eastern MA, located on the water.

We have no central AC but want to install AC. Tankless hot water is appealing though our water tank is new.

Please advise if possible. I am investigating Navien, Burnham, Lochinvar, Viessman.

-- Ann Tauro

In Mechanicals | Asked By Ann Tauro | Nov 21 16
2 Answers

Who is responsible for maintaining a record of the layout of private citizen's septic system to be sure their system meets regs?

We had a water test come back from Endyne as positive for E. coli. As a matter of course we of course thought of our nearest neighbor as leaking human fecal matter into our driven well system.

Upon calling the town to find out what kind of septic system our neighbor has, the town indicated that they did not have a record because of the age of the system.

In General questions | Asked By Stacey Gates | Nov 19 16
5 Answers

Redundancy of taping and caulking XPS

On my wrap and strap I'll be taping joints on the xps with siga sicrall. Will caulking the joints in addition be an unnecessary redundancy that I can save some money by avoiding?

In General questions | Asked By Daniel F. Vellone | Nov 19 16
0 Answers

7' x 7' sky light with a low U Factor

I need to replace a 7' x 7' skylight in a condo in Boston. I'm looking for a product withe a low U Factor. I've spoken to Wasco, and they said they can't make any of their eco products that large, so I'm stuck with their standard acrylic dome and a U Factor of 0.64.

Has anyone seen another skylight product that could be manufactured at that size with a low U Factor?

- Adam

In Green products and materials | Asked By Adam berrey | Nov 21 16
2 Answers

Construction sequence for mineral wool insulated double walls?

This concept is base on the assumption of a PWF with it's top flush with the bottom of the sub-floor but may be adapted to other situations. My current plan is 2 ea 2x4 walls, both sheathed on their outer faces. Fiberboard on the outer and OSB on the inner. I I hope to use 3 layers of 3 1/2" mineral wool bats. I'm thinking that it may be possible to build all 3 layers on the sub floor then erect all at once as an assembly.

In Green building techniques | Asked By Jerry Liebler | Nov 20 16
99 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

In Energy efficiency and durability | Asked By Susan Hanway | Aug 28 16
2 Answers

Is this a better way of installing tubing for radiant floor heating?

This is a build residential build in Germany. I found it interesting because as you can see the tubing was added after the walls, framing, etc had been built whereas in the on this site I typically see PEX being incorporated into the slab itself.


In Mechanicals | Asked By Chris M | Nov 17 16
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