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13 Answers

Space and water heating for a micro-load house

I've been re-reading Martin Holladay's posts on water heating as I once again deal with a small-ish super-efficient house: 1900 ft2 with a heating load of less than 20 kBtu/hour. The homeowners have access to propane and electricity and here in MN, electricity is still generated by a lot of coal, although the homeowners are planning for a pv system.

At the moment I've narrowed heat/hot water system ideas down to three:
1. use a 6kW modulating electric boiler for space heat (hydronic radiant) and also to fire to an indirect tank for hot water. Also, use a drainwater heat recovery device.

In Mechanicals | Asked By Rachel Wagner | May 14 13
7 Answers

Does this plan for a vented over-roof make sense?

Hi all, first time asking a question but I’ve found this Q&A very helpful in the past. Thanks in advance for your help.

I’m planning to add a vented over-roof to my zone 6 northern NY house. It has three roof sections: two cathedral and one with an attic. I’ll be dense packing the cathedral ceilings with cellulose and spray foaming the attic before over-roofing, making all three roofs hot and roughly R-25+ before the over-roof. Here’s the thinking on the vented over-roof layers, from bottom up:

1) Decking
2) Air barrier membrane

In Plans Review | Asked By Jan Wellford | Oct 3 14
10 Answers

Sleeping coves betters than medium sized bedrooms?

I redesign old homes and rent them out. I found hallways are your worse enemies in use of space. It was not until this last year that I noticed hallways in my rentals that I didn't mean to make.

Lets take a bed of roughly five foot by seven foot for example. If I put this bed in the middle of the room with the headboard on a wall and put three feet around the bed I get a 11 foot by 10 foot bedroom. A typical bedroom size plus or minus. In this typical bedroom I have a roughly five foot by two foot closet.

Current Rental / Bedroom / Square Footage

In Interior design | Asked By S E | Oct 13 14
5 Answers

Does the Air Scrubber Plus need the fan on continuously to work properly?

I had the Air Scrubber Plus installed on my central unit. I understand the fan helps the product purify the air. I'm concerned the fan will burnout if it is on all the time. Can you tell me if I need to leave the fan on 24/7 to support the product? If do, will continuous blowing damage the fan?

In General questions | Asked By Ann Cobb | Oct 12 14
7 Answers

Outdoor catalytic wood stove: smoke reduction devices

Hi all,

We have an outdoor catalytic wood stove with an 8-inch pipe, and our neighbors want us to cut down the amount of smoke. It sometimes drifts over in their direction... We live in the Northeast US and it's starting to get cold around here!

We found this Catalytic Add-on Stove Damper online:

http://www.woodmanspartsplus.com/748835/products/Catalytic-Add--On-Stove...

In Green products and materials | Asked By Alex Forbes | Oct 13 14
7 Answers

ERV or HRV that scrubs the incoming air?

Hello all, I'm planning a new home and need some help on a ventilation issue. A couple of my neighbors burn a lot of wood in the winter, so much that you smell like a BBQ pit after a few minutes outdoors sometimes. Is there any ventilation system on the market that would scrub incoming air--activated carbon maybe? Or can anyone think of way to alter ventilation ducts on a typical ERV or HRV to do so that is safe for the systems and for me?

In Mechanicals | Asked By Antonio Oliver | Oct 9 14
2 Answers

Bathroom venting concerns

I have a 2 story/2-unit balloon-frame building from 1929, plus a hip roof. The 1st and 2nd floor bathrooms are on top of each other on the back center of the building. Both have fans, but neither vent to the outside!! We have mold/moisture concerns in the back rooms of the house. No wonder.

Venting each fan has a separate issue.

In General questions | Asked By A. Bradford | Oct 12 14
6 Answers

How do I cost effectively insulate the ceilings of my detached garage?

I have a 22x22 detached garage with a 15x15 addition on the back (both gable roofs) that I'm turning into a shop. I live in Iowa and have run a gas line to it and have purchased a gas heater capable of heating. I would like to heat the garage at low heat and will crank it for shop time. Each space has 2x4 rafters, but no insulation, no ridge vent or other roof venting and only one of the two spaces allows free flowing air to enter the building through the rafters running beyond the building envelope as the 22x space has wood blocking.

In Energy efficiency and durability | Asked By Matt McDevitt | Oct 12 14
9 Answers

How can I attach a ledger to an outside brick wall for a deck?

How can I attach a ledger to an outside brick wall for a deck when foam is used on the outside of sheathing?

I have 3 inches of foam then a 1 nice air gap, and I need advice on how to attach the ledger.

In GBA Pro help | Asked By michael kasales | Oct 9 14
5 Answers

Truly "smart" thermostats and boiler controllers?

Well, my new boiler is in (a Lochinvar WHN-85, with a Lochinvar SIT 40 indirect water heater). As far as I can tell this early in the season it's working fine. But, I've been thinking about my thermostats and how they communicate with the boiler, and wondering if there might be a better way.

My old boiler was a standard dumb boiler. Each circulator was on if its thermostat was calling for heat, and the boiler was on (full blast) if a circulator was on and the water temp wasn't at the limit. True bang-bang control.

In Mechanicals | Asked By Daniel Griscom | Oct 11 14
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