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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
15 Answers

2/12 cathedral roof replacement


I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

In GBA Pro help | Asked By mark kessler | Feb 23 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
22 Answers

Mitsubishi mini split behaving very differently with external thermostat vs. without

I am able to monitor my home's electricity use and I always thought it was a little weird that my Mitsubishi FE18NA heat pump seemed to constantly be spiking up and down, considering that the whole idea of the inverter-driven compressor is that it can run smooth and steady... fast forward to yesterday when I received my MHK1 thermostat and hooked it up. Suddenly, the power usage was steady as a rock.

In Mechanicals | Asked By Nick Welch | Jan 6 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
14 Answers

Bug screen for rainscreen strapping...how wide to cut?

I'm a rookie with this. First time building a rainscreen. I've got my WBB on the house and would like to apply my 3/8 strapping to create and airgap.

I picked up a few hundred feet of 4' bug screen and I will first apply a layer top and bottom, then my strapping and then staple the bug screen on-top of the strapping making the air gap, hopefully, bug free.

In General questions | Asked By Mark Helmrich | Mar 18 15
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