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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
3 Answers

Foil tape inside duct?

I have several heat registers that I can access the duct from the inside only on, a few as far as 2 feet into them. Some just have seems, one has a good 1 inch gap on one side. (I'll try to hammer that together from the inside.)

Anyway, I've read that mastic can dry out on the inside of ducts, but have read conflicting suggestions about foil tape. I have this tape right now, should it work on the seems inside the duct, in the last 2 or so feet before the register?

http://www.homedepot.com/p/Nashua-Tape-1-89-in-x-50-yd-322-Multi-Purpose...

In Mechanicals | Asked By Jeremy M | Mar 23 15
2 Answers

thicker walls -- [Not really a new thread]

The interior is gutted to the studs. Was going to replace old isolation with R-15. Will be residing in the future. Vinal is brittle and we are replacing all windows. Doing all the work myself so it's just what I think I'm worth.
Thank you

In General questions | Asked By Scott Neels | Mar 23 15
2 Answers

Hard or flaccid?

I am advising my friends on their 50s ranch upgrade with full basement. The house could never be made energy efficient unless it was completely torn down and rebuilt. They have a lower seer HVAC system that is a tad bit over-sized and runs like a top. Their GC wants them to completely rip-out the very accessible (full basement) hard HVAC duct and install a new system for 16k+ not including 18% markup (estimate with no manual J or D, to go by I might add), because their system is "too leaky" which he summarized by just eyeballing it.

In Energy efficiency and durability | Asked By leo kloop | Mar 23 15
9 Answers

New PHIUS+ 2015 released and in effect as of March 16th, 2015

Interested to hear comments on the new PHIUS + 2015 that went into effect on March 16, 2015. They made a lot of changes and the biggest being the each climate zone and specific area will have its own standards. Not one big gigantic fits all approach like PassivHaus but very specific to climate zones, house size, etc.

Read more here:
http://www.phius.org/phius-2015-new-passive-building-standard-summary

In Green building techniques | Asked By Peter L | Mar 20 15
2 Answers

Insulating basement ceiling/first floor

I suspect this has been much discussed, so feel free to bump me over to a thread if one exists...

We have a relatively modern (1981), reasonably efficient gambrel in Maine. Full basement, concrete foundation, unfinished (used for storage and a workshop. Not heated, but gets residual heat from the oil boiler. Temp hovers between 50 and 70, depending upon what the boiler is doing.

In General questions | Asked By John Gold | Mar 23 15
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