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1 Answer

insulation type, etc.

hi all,

i have a semi-detached brick 2-family home in brooklyn. 20' x 65'. tenants are on the top floor and we occupy the first 2 floors. our ground floor is about 3 feet in ground on 3 sides and at grade in the rear. we are renovating and intend to put 2 full bathrooms and 3 bedrooms there, in addition to the laundry and utility room. we recently install a navian ncb240 which currently serves our dhw and baseboard radiators for both floors (tenants have separate boiler).

In Energy efficiency and durability | Asked By josh millis | Oct 1 15
1 Answer

polyiso along ceiling under truss chords

New build in climate zone 5. My plan is to establish my air barrier on the outside with zip sheathing and liquid flashing, and want to continue the air barrier across my ceiling (below a vented attic with blown cellulose). I thought about continuing the zip panels across the ceiling attached under the truss chords and tape them from the inside. I want to have options for drywall and tongue and groove wood for different rooms. I also thought about running polyiso boards in the same manner, maybe in two layers with staggered and taped seams. Any thoughts on this option?

In Energy efficiency and durability | Asked By Brian W | Oct 1 15
3 Answers

crawlspace foundation with wing insulation as well as vertical exterior insulation?

Hi. In northern New York state, climate zone 6. Preparing to build a 20 x 30 second home for a client that will be insulated but not heated for the foreseeable future. Some day it might be used year round.

Crawlspace foundation with footings to frost depth. We are planning to insulate the stem walls on the exterior with 2" XPS. A slab is planned at level of footing. We are contemplating skipping the sub-slab insulation of 2" XPS and adding wing horizontal wing insulation instead--in addition to the vertical stem wall insulation.

In Energy efficiency and durability | Asked By Jon Brown | Oct 1 15
1 Answer

Sub-slab condensate drain

This article mentions running a condensate drain for a mini-split to a leaching system under the slab, or tying it to the radon pipes. Is this a common/recommended technique? If tying to a DWV system risks leaking sewer gas through a dry trap, doesn't this system have the same risk for radon?


In Green building techniques | Asked By John Ranson | Sep 30 15
2 Answers

Insulating a pole barn

Hi. I am interested in building a small (20'x20') eco friendly pole building as a "tiny house". I like the idea of a pole building because it avoids the use of concrete for the foundation. I plan on using perlite bags beneath an earthen floor as the "sub-slab" insulation. For the walls and ceilings, I would like to use cellulose. I have not been able to find any details online for appropriately insulating and air sealing pole buildings. What resources I have found generally ignore thermal bridging entirely, for instance.

I would like to achieve R-40 walls and an R-60 roof.

In Green building techniques | Asked By Steven Gubkin | Sep 30 15
0 Answers

If you install a Dedicated Recirculation Line, can you have it run on demand? Or does it have to run continuously?


I'm trying to figure out the benefits/drawbacks of installing a Dedicated Recirculation Line versus an Demand- Initiated Recirculating System. I've already read Martin Holladay's great article in Fine Home Building.

Clearly, the demand-initiated systems are better suited for retrofits since they use the existing cold water line (at least the D'mand one I'm familiar with). And the Dedicated Recirculation Line is better for new construction due to the cost of installing additional plumbing back to the water heater.

In General questions | Asked By Whitney Larsen | Sep 30 15
28 Answers

Rhode Island remodel

My wife and I are in the process of purchasing an 1100 sq ft 1978 ranch in western RI (zone 5A). The existing house sits on an ~800 sq ft unfinished basement with the western (24') and northern (36') walls above grade/walk out.

Our plan is to finish the basement at the kitchen/living areas and re-model what will then be the 2nd floor as 3 beds, 2 baths, a laundry and a study.

In General questions | Asked By Ben Balcombe | May 5 15
13 Answers

Radiant floor heating, Boiler vs. Air to Water Heat Pump

Hi all, first time poster, but have gotten some great advice from this site during my project. I finally signed up and decided to post regarding a question about how to heat my radiant floor as we move fwd on my home build. First a little background on my project.

Our house is a 2300 sq/ft 3 bed/ 2.5 bath, single level home located in Parkdale OR, with what looks to be zone 5 climate. We typically get a good solid several month run of temps around the low to mid 30's with several weeks that will drop into the teens or single digits depending on temp.

In General questions | Asked By nick dills | Sep 29 15
1 Answer

What is best insulation process for addition

We have a Mobil home built 2007. We are adding an addition on north side 14 feet out 70 feet long. Do we use 6 inch walls or regular 3 inch walls, with what type of insulation. We live I southern Illinois where it can get below zero. Also will we need another heating source.furnace IA all electric , vexar by york. We are trying to keep this afordible and hear and cooling efficiency.

In Energy efficiency and durability | Asked By Victoria Harmon | Sep 30 15
10 Answers

Solar in upstate NY?



In Energy efficiency and durability | Asked By Jason Crawford | Sep 27 15
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