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8 Answers

Options for hydronic air handler control: properly coordinate ECM blower motor and variable-speed condenser compressor


First post. Not sure if this is best in Mechanicals or Energy Efficiency. Please move as you see fit.

High level: Replacing condenser unit and air conditioner coil. Since the work is being done, now is the time to upgrade the air handler mechanicals and controls as well. I need help understanding options for properly coordinating an ECM infinitely variable blower motor with a multi-stage/variable speed condenser compressor. And this needs to work with my hydronic heat too (currently air, but will be adding radiant at some point).

In Mechanicals | Asked By D D | Aug 10 16
3 Answers

How to use Zip with continuous insulation stucco systems?

I live in Denver and am building a custom house that I am hoping to have at lower than 2 ACH50. I see more & more construction using ZIP, so I wanted to use it as a first step toward a tighter house. Additionally I would like to utilize continuous insulation on the exterior to deal with thermal bridging. However the architectural design calls for stucco.

In Energy efficiency and durability | Asked By Tracy Lewis | Aug 12 16
2 Answers

NuLEDs or Lotus Ultra Slim LEDs?

Has anyone inquired or used NuLEDs in a residential project? They are the lighting over Ethernet system that was talked about on here a while back. I messaged them but haven't heard back.


Also, I was curious if anyone has had luck with the low profile Lotus LED can lights, or something similar. I was looking to use them in my 2x4 furred down service area under my ceiling air barrier.


In General questions | Asked By Brian W | Aug 9 16
7 Answers

Vapor-reducing sealer for concrete / brick?

My house is in zone 3, marine/coastal, on the water, so really humid much of the year. The house is on pilings with the ground level a concrete slab with a single wythe of brick infill in between the pilings. I have a ~500'^2 workshop area I'd like make reasonbly dry for tools, etc.

What would be the appropriate sealer to apply to the concrete floor and brick to help reduce the water vapor transmission up through the concrete floor and from the outside air/rain through the brick?

In General questions | Asked By DIY Owner | Aug 11 16
19 Answers

Mitsubishi minisplits — horizontally ducted

Sorry - I blv I posted the same in another section. Please ignore this question if it's a duplicate.

We are not fans of ductless units. Therefore, we opted for the hidden horizontally ducted units that Mitsubishi provides. Unfortunately, all the Mitsubishi contractors we talked to have never designed a home with these type of units. Plenty of ductless experience.

In Mechanicals | Asked By Ismail Mohammed | May 21 16
6 Answers

Subfloor cavity question: Method in the madness?

Just posted this morning about a bathroom remodel I'm doing. Got some great feedback. Thanks much. Now I've encountered a different problem, and I didn't know if I should tack it on to my previous question or just post separately. I've obviously opted for the latter.

In GBA Pro help | Asked By Doug Waugh | Aug 4 16
15 Answers

Hybrid cut-and-cobble foam board with batts in upstairs bathroom exterior walls?

I have a house in Columbus, Ohio (Zone 5) that was built in the early 70s, and I'm in the throes of a complete upstairs bathroom remodel. I've gutted the space down to studs (even replaced the subfloor), but I've opted to keep the cast iron tub. Well, I'm ready to insulate, but as I read the Q&A exchanges on this site (and several others), I realize that my options are limited. The original insulation schematic included black fiber board sheathing on exterior, unfaced fiberglass batts between 2x4 studs, and a 4mm layer of plastic as a vapor barrier over the whole thing.

In GBA Pro help | Asked By Doug Waugh | Aug 4 16
1 Answer

Insulating an outbuilding in the rainforest

I am in need of some second opinions. I am in the process of building a 10'x14' shop space with close to %100 salvaged materials I have been acquiring over the last several months. The shop is going to have a metal shed roof, 14' sloping to 12' and there will be a sleeping loft in half the space for occasional guests. I will be heating with a woodstove, most likely every day of the winter. There is no electricity, bathroom, or running water inside the shop. The location is Olympia, WA which gets over 50" of rain a year and is a hotbed for mold and mildew.

In General questions | Asked By Henry Stevens | Aug 11 16
2 Answers

Does this EPDM roof have seams?

I just had a roofing project completed and the roof area was small enough to accommodate one single piece of rubber roofing so I told the contractor that is what I would like to use.

In Energy efficiency and durability | Asked By Damon Beck | Aug 11 16
3 Answers

Mitsubishi multi-split — one indoor unit is not producing cool air


We had a new Mitsubishi multi split system installed early this year with one outdoor unit hooked to 5 indoor units.

Couple weeks ago we were turning on the entire system for the first time (we had a long indoor furnishing work done by ourselves) and found two of the 6k indoor units had problems:

1) One of the 6k unit does not produce cool air
2) while the other one would automatically shut off due to communication problem with the outdoor unit (per troubleshooting guide based on indicator flashing pattern).

In General questions | Asked By Kin Chan | Aug 6 16
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