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2 Answers

Electrostatic air cleaner for HRV intake?

I live in an area with a lot of airborne dust/dirt (nearby highway and railroad, among other sources) and have been quite pleased with the Honeywell electronic (electrostatic) air cleaner on my forced air furnace return. It removes significant quantities or dirt.

In Mechanicals | Asked By Stuart Friedberg | Jan 13 16
7 Answers

Does anyone make a barbed fastener specifically made to fasten a sheet of foam to another sheet of foam?

I have an attic knee wall area that I'm insulating with reclaimed 1 lb eps sheets. I ha e hundreds of sheets available. I'd like to use cap nails to secure the first layer of foam directly to the knee wall studs. I would tape foam seams. Since I have a large amount of sheets available I would like to apply 6-8" of foam to the exterior. Is there any device like a push pin that is designed to fasten subsequent sheets of foam to another? Since the foam is non structural it just needs to make a tight connection and maintain grip to the other sheet.

In Green building techniques | Asked By Rick Van Handel | Jan 12 16
11 Answers

Mini split efficiency

After reading the articles, questions and answers on this site, over the past few months, i am convinced and saddened that my new mini split system, installed last fall, is likely ginormously oversized.
2 Mitsubishi FH 09's - 1 in each of 2 bedrooms totaling ~ 400 sf. An FH18 for ~ 600sf. House is 1989 rancher with 1000sf, insulated crawl space, zone 4. Attic insulation is 2 layers R19. 8 double pain Pella windows, 1 double pane slider, standard steel front door. Outdoor unit isMXZ3C0NAHZ. Is there any hope that this system can be used efficiently?

In Energy efficiency and durability | Asked By Julie Mccormick | Jan 12 16
1 Answer

Want to add A-frame type gables (screen room) to existing plan

I have plans to build a Log home that has a 10/12 Roof in design. Want to add a Screen room..in a gabled A frame design to back of house. One contractor says its not good idea, but I have seen MANY attached Screen rooms on the internet....they seem to attach to house by cutting back eaves and building a A frame Screen roof on top of existing roof. One internet site used a "Cricket Roof" to divert water from coming into Screen room from roof.

In GBA Pro help | Asked By Kenneth | Jan 13 16
1 Answer

Floor sheathing insulation

I'm working on a home that has a shoddy plywood floor on joists (some sleepers too). There is no real crawlspace, and no budget to dig one. I am interested in improving the thermal performance of the floor...

Is there any precedent for an insulated sheathing? I Can't figure out how else to improve the thermal performance of the floor. Perhaps just a thin foam underlay and cork flooring and call it a day?

In Green building techniques | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Jan 13 16
11 Answers

Kneewall and radiant barrier?

I recently bought a house in Jacksonville, FL. Part of the attic is finished into a loft with a knee-wall construction. It got quite in the loft last summer relative to the rest of the house, and I'm looking at ways to cool it down a bit.

In Energy efficiency and durability | Asked By Craig | Jan 5 16
1 Answer

Black vapor barrier paper

Hi all,

We will be renovating a guest house that dates back to the 1700s. We'll be abating the lead and asbestos, and the environmental report found "black vapor barrier paper" Chrysotile-70% behind the siding. We had originally thought that the siding was original to the house and dating back to the early 1700s. However, it appears that the asbestos paper may indicate that the siding is from a later time. Does anyone know when asbestos-containing "black vapor barrier paper" started being used in the U.S.?

Thank you!

In General questions | Asked By J C | Jan 13 16
19 Answers

Hot Water Heater

We're in need of a new hot water heater because our current one has failed. What type of hot water heater is best? A stone heater has been recommended to us as an option. Is this an ideal option? Thank you!

In General questions | Asked By J C | Jan 12 16
14 Answers

Can whole house dehumidifiers be "daisy-chained" to give higher levels of dehumidifying?

I live in the humid mid-Atlantic region. For health reasons, I have a "balanced" "fresh air" ventilation HRV integrated into my home HVAC system. We also added a "whole house" Dehumidifier system [like all such residential systems, it is a bypass system instead of acting to dehumidify the ENTIRE return air stream] consisting of a Honeywell DR90 [max. 90 pints/day]. Our local "expert" HVAC service company recommended the DR90 as being max. size appropriate for our 2k sq.ft.

In General questions | Asked By Terry Sopher Sr | Jan 11 16
11 Answers

Radiant slab in garage: boiler vs. tankless vs. tank

Hi all, first post. I have been doing a lot of research (on this site and others), talking with manufacture's, etc. about my setup. Nothing too complicated, I have a new 36x30 detached garage. Walls are 2x4, 22' of the 36' is attic space with 2x8 joists, the remaining 14' is cathedral 2x12 for a lift someday.

In General questions | Asked By Eric | Jan 10 16
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