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2 Answers

Where is the building envelope?

Doing several additions with new gable roofs overlaying the existing roof. New and existing roofs will have foam the underside of the roof sheathing. The question centers on where the envelope should be on the triangular overlay portion of the new/old roofs and should that triangle be vented in anyway.

In GBA Pro help | Asked By Robert Brown | Mar 24 15
12 Answers

Cool roof on a rigid foam retrofit


I have been doing extensive research prior to begining my remodel on my new home. I would like to get some advice on how to aproach my remodel.

The home is a 2600 sq ft contemporary style house. The majoroty of the roof is an unvented catherdral roof assembly. It is a simpole gable roof, although the North face is much steeper. It currently has an aging asphalt roof that will need replacing soon. I am planning a PV array instalation and need advice on what sort of assembly would be the best combination.

In Green building techniques | Asked By David Mosijchuk | Mar 23 15
3 Answers

Help with rainscreen options and cost for insulation on 1970s remodel

Hi, I am in Zone 4, Portland, Oregon.
My existing 1970's home is two stories with 2x6 framing with ) insulated walls(probaby still R13 in a daylight basement. Top floor main living room has 2x4 walls (R13). Existing Sheathing is Fiberboard sheathing (Cellulosic Fiber Insulating Board,).
I am tearing off existing combination of T111 and some other wood composite lap siding and installing a new rainscreen + fiber cement cladding, + new windows.

My Questions are:
1) What are the best cost effective option for a rainscreen layering if my fiberboard is intact and re-usable?

In Green building techniques | Asked By tauran ivall | Mar 24 15
6 Answers

A different use for earth tubes or pipes

I have been intrigued for a while by the potential of Earth Tubes (most significantly discussed here at: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/my-earth-tube-story'rel="My Earth Tube Story"'. I have a project coming up that will involve regrading, earth fill, and irrigation installation on a sloped half acre, so I may have the opportunity to bury some pipe (4-6ft deep, climate zone on the line of 5/6), if it seems worthwhile.

In Energy efficiency and durability | Asked By Stuart Miller | Mar 23 15
1 Answer

Obnoxious blinking audio ads

I have clicked on a few ads. But will only support those that display motionless still quiet ads. More than that and you lose me, and forms of violence could well takeover an individual.

Pushy ads suck.

In General questions | Asked By aj builder, Upstate NY Zone 6a | Mar 25 15
2 Answers

Fiber cement siding over furring strips

In our region, which gets an average of 37" of rain annually, most folks put fiber cement siding against House wrap on OSB. Though there have been some projects we have seen that put the siding directly to the framing with no sheathing. In short order this is quite apparent because of the noticeable wave in the siding. We would like to start using furring strips on top of well sealed foam sheathing to create a drain pan. But we are afraid of the wave. We do quite a few resides and are typically dealing with 16" OC framing.

In Green building techniques | Asked By Hugh Stearns | Mar 24 15
5 Answers

What is the best way to manage moisture in a cinder block building in a hot, humid climate?

Having rebuilt my tiny bargeboard shotgun house in New Orleans, I now wish to turn my attention to the garage. Unlike the house itself, which has a pier foundation and a wood frame, the garage is a cinder block building on a concrete slab.

In Green building techniques | Asked By Shannon Holman | Mar 20 15
6 Answers

Small addition

I am in the early design phase of a small (12'x20') addition for a client in climate zone 5 and am just looking for suggestions as to the best new construction insulation & air sealing details to use.

It will be wood frame construction with a crawl space and a gable roof with vaulted ceilings inside.

I am leaning toward the zip wall sheathing system on walls & roof deck with a rainscreen on top and fiberglass batts in the 2x6 stud bay. Is the zip wall roof sheathing of sufficient thickness to allow me to build an unvented roof without having to spray 2-part foam on the underside?

In Energy efficiency and durability | Asked By Jason Schatz | Mar 24 15
6 Answers

Filtration and humidification with mini-split systems

I have a customer with allergies. Her existing GFA furnace has a high efficiency filter and a humidifier.

In the new (air sealed and super insulated) home we are designing for her, we are planning to use Fujitsu mini-splits for heating and cooling and a Honeywell ERV for ventilation. Specs for these units indicate a washable filter but no MERV rating.

In Mechanicals | Asked By Terry Herschberger | Mar 23 15
3 Answers

Thicker walls

I live in Minnesota. I'm remodeling an older home with full 2x4 studs. On the outside there is a layer of 1 inch buffalo board and 1 inch foil covered foam.
Is it worth the time and money to add wood strips to the 2x4's to make them 2x6's on the inside and go from a R-15 to R-19 or 21 insulation or add 2 inch certifoam to the outside or should I just leave it alone with 2x4 walls and R-15?

Thank you

In General questions | Asked By Scott Neels | Mar 22 15
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