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13 Answers

Heat pump hot water heater tank size

Family of 4, 2.5 baths, dishwasher and washing machine in our house. We have a 20+ year old RUUD electric hot water heater w/ a 50 gallon tank.

We are most likely going to upgrade to a heat pump hot water heater - we live in Virgina, have an unconditioned basement that could use dehumidification, and have no gas connected to our house.

My question is what size HW heater to get. My initial thought was just another 50 gallon one, because our current HW heater has seemed sufficient. But then I read this:

In Mechanicals | Asked By austin jamison | Jan 17 14
13 Answers

New windows — siding and insulating

We are needing to install new windows (which we've purchased) with nailing flanges. We currently have steel siding and realized that there wouldn't be a great way to install the windows without taking siding off. The siding has come of fairly easily, but we've discovered two additional layers of siding under our steel siding, which has made it virtually impossible to properly install the new windows.

In Energy efficiency and durability | Asked By Matt Cibula | Oct 28 13
3 Answers

Covering for 2-inch rigid foam at base of siding?

I am considering a 2x6 wall assembly covered with plywood sheathing plus 2 inches of rigid foam under fiber-cement siding with a rainscreen. This will probably go over an ICF foundation.

I am not finding a detail for this specific situation, but similar details on GBA suggest having the sill plate align with the ICF. This will mean that there will be 2" of foam exposed at the bottom, projecting past the foundation.

In Energy efficiency and durability | Asked By Hallie Bowie | Jan 23 14
1 Answer

Detail at REMOTE Wall & Lower Roof Connection

I'm in the design state of building a REMOTE house in climate zone 6A. I'm looking for a detail showing a lower roof line connecting to a REMOTE wall. How is waterproofing on the roof best dealt with at the wall intersection?

I've seen photos showing installing the EPS before the lower roof truss to allow for continuous insulation but cannot find anything showing how the waterproofing on the lower roof is then tied into the REMOTE wall.

In Green building techniques | Asked By Brad Kemis | Jan 24 14
7 Answers

What is the best way to insulate a slab on grade home on top of the concrete?

This is a new slab in northern Minnesota.

In Energy efficiency and durability | Asked By Richard Regnier | Jan 23 14
5 Answers

Any compression issues with 7" of EPS?

Thanks for the previous advice, One more, I have EPS with backing material in my area at 1" thickness only it has 10 PSI rating. I want to place 7 layers,is compression a facter in zone 6 with reboard and rubber thanks

In Energy efficiency and durability | Asked By Robert Mason | Jan 22 14
4 Answers

Cellulose vs. stabilized cellulose?

Most of the cellulose going into walls here is stabilized cellulose. We had a new insulation contractor tell us this week that he will only put in loose cellulose in walls. (by loose I mean no glue). He said he nets the stud cavities and blows it in at 3.5#/inch, so there will be no settling over time.

He also briefly mentioned that 'they' were starting to find serious issues with the stabilized cellulose product, but we didn't get into that.

Any issues with this method? How do I know the density really is 3.5#? Is there any way to check it?

Will it not settle over time?

In Energy efficiency and durability | Asked By Allen Brown | Jan 22 14
7 Answers

How best to balance an HRV's intake and Exhaust?

I got my ecoEnergy Retrofit final energy evaluation back, it's a Canadian retrofit program. The house scored an 84 out of a 100. The evaluation report doesn't actualy provide an meaningful information, just the score which is used to calculate your rebate. Most of the marks were for the geoexchange system I put in!

I called up the evaluator and was able to get some useful information from him. The ACH50 was 1.85, the ACHnatural was 0.080 and the equivalent leakage was 72 in^2.

In Energy efficiency and durability | Asked By Andrew Henry | Nov 20 09
4 Answers

Any volunteers want to help the Appraisal Practices Board with "The Valuation of Green Buildings"?

The Appraisal Practices Board (APB) of The Appraisal Foundation is looking for "Subject Matter Experts" for a project called "The Valuation of Green Buildings."

According to the application form, "We foresee that an average of four hours per week will be devoted to this process with one to two face-to-face meetings. SME ("subject matter experts") members will be reimbursed for travel expenses associated with this project according to the reimbursement policies of The Appraisal Foundation. However, SME members will not be compensated for their time in the form of an hourly rate."

In General questions | Asked By Martin Holladay | Jan 21 14
1 Answer

Tiling a painted floor

I have a basement that I would like to tile. The previous owner painted over the floors and said that there may be old lead paint underneath the upper layers. Because of this, I'd like to leave the paint undisturbed which, from what I gather, will present some problems for tiling. If I want to keep the paint in place, does this limit me to floating tiles? I have also heard of glue down cork for use in basements. Would either of these two options be good alternatives or might there be a better option? Thanks.

In General questions | Asked By Kevin Schramm | Jan 22 14
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