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20 Answers

R-value vs. thermal mass


In GBA Pro help | Asked By David Epley | Jan 26 12
8 Answers

SIP home with 2 air handlers for open space floor plan?

Plans / pics are attached

Exterior walls are SIPs R-24 with 1-1/2" EPS stucco
Center 'bumpout" is typical 6-9 stick with 3" EPS (interior to be sprayed)

WIndows are Integrity Low E3

window wall south facing

Proper way to heat and cool

We are in the process of building a very open floor plan home with catheral ceilings in CT (zone 5) with 2 levels.

Main level - 9-17' ceilling heights
Lower Level ( Walkout) has radiant in an exposed slab and footings over 2"EPS.

In Mechanicals | Asked By Chris van Wilgen | Feb 5 13
1 Answer

What is the best way to plaster an exterior wall insulated with straw bales?

We are wondering if it is wise to plaster directly on the 2" mortar that protects the straw bales or if we should use furring and plywood on which we would fix a screen to put the plaster on. It would add an air gap between so that the wall could dry better but we don't know if it is worth it.

What do the experts think?

In Green building techniques | Asked By Serge Bedard | May 1 13
1 Answer

Link to Building America study on exterior insulation retrofits

Here is a link to a recently published Building America study on several exterior insulation retrofit projects:
Project Overcoat — An Exploration of Exterior Insulation Strategies for 1½-Story Roof Applications in Cold Climates

In Green building techniques | Asked By j chesnut | May 1 13
8 Answers

Wall design in renovation - with moisture issues

Sorry in advance for the long question. it seems important to establish the full context because i've been unable to match my circumstances to the thousands of articles i've read here and other places.

Zone 5a/6a border (Hudson valley, ny) 1959 slab on grade, standard 2x4 framing single story house.

It's cut deeply into the hill, and the entire back of the house is 2 feet away from a 3-5 ft high retaining wall. ugh.

The house is environmentally almost a walk in basement. high humidity levels, and, no surprise, mold. solving the moisture will hopefully help the mold issues.

In General questions | Asked By kikiyut 555 | Apr 30 13
5 Answers

Spiders, flies, ladybugs, hornets and beetles

I have just installed both range and bath vent fans and 4 passive air inlets. We live in big orchard and farm country where the flying and crawling insect populations are often swarming. When they hatch they can reach infestation levels.

None of the fan and make up air products have adequate protection and none have exterior (intake side) filters. The Panasonic and Aldes products are particularly weak in this area.

In Mechanicals | Asked By Oak Orchard | Apr 30 13
2 Answers

Insulating brick from the exterior

I am renovating an end-of-group brick rowhome in Maryland. The home was built in 1914 and has 8" masonry load bearing walls. The owner is interested in exposing the old masonry walls on all (3) exterior sides of the building. To do this I will have to insulate from the exterior and install new cladding. I am not confident in installing 4" or so of rigid insulation on the old masonry, mostly due to cost/ performance of fasteners that long into the old masonry. The rainscreen and new cladding will also be relying on the same type of fastener.

In Green building techniques | Asked By Charles Chiampou | Apr 27 13
8 Answers

Heat loss calculus: solar heated siding and air space

I would like to discuss about the implications on heat loss calculations of temperature of exterior finish and its different layers (notably air space) and its effect on the delta T .

I have not found much info using the search, rather some mentions about the effect etc.. Maybe I am not using the correct terms to look it up?

So basically, when we are calculating the heat loss of an area using HDD or simply a specific time delta T, how is it affected?

A dark grey finish with a 3/4 air space under it should get pretty hot during day time when the sun is shining high...

In General questions | Asked By Jin Kazama | Apr 24 13
2 Answers

Help! My house has its HVAC ducting outside the envelope

In my area in Central Virginia, it is 'fashion' to install HVAC duct work outside the controlled envelope of living space. First floor ductwork is in the crawlspace; 2nd floor ductwork and the upstairs air handler is in the attic. Everything I've read in FineHomebuilding warns against this, but apparently local builders aren't reading FH. So, what am I as a homeowner to do within reason to remedy this situation? What is the most cost-efficient course of action short of creating new duct chases throughout the house?

Thanks -
owner of a gas guzzler home built in 2003 :(

In Energy efficiency and durability | Asked By Mitchell Teixeira | Apr 24 13
4 Answers

Waterproof tile backer

Is there a waterproof tile backer for a tub surround which can be used for a period of time prior to the application of the finished tile surface?

In General questions | Asked By Morgan L Washburn | Apr 29 13
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