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4 Answers

Making your own minisplit linesets?

I have purchased several Mini-splits for a rental building I manage (which currently touts window ACs (yuck!)).

With the cost of linesets being so relatively high, what is the problem with purchasing copper and cutting and flaring my own. I have purchased a couple of sets, but find nearly 6 of 12 feet is coiled. I am contemplating cutting in half and reflaring...

I understand the flares are different. And, thus far I havent found a good source of the flare nuts for the new refrigerant. Suggested sources?

In Energy efficiency and durability | Asked By John Granoski | Jul 1 14
4 Answers

HVAC HRV sized correctly for my home?

A HVAC contractor installed a Venmar HEPA 3100 HRV in my new construction home. I was wondering if it is sized correctly for my house and meets the international building code and international mechanical code requirements. HVAC Work began in 2011 but venmar was installed late 2013.

My house is:

4846 square feet with a 486 square foot attached 2 car garage. Total sq ft: 5332.
Bedrooms: 5, Bathrooms: 6..

I was ordering a new filter and noticed it was discontinued and said:

for homes up to 3100 square feet ***
*** for new construction refer to building codes.

In Building Code Questions | Asked By Sam Miller | Jul 4 14
5 Answers

Advice on passive air inlets with bath fan exhaust ventilation?

Background: new construction, climate zone 6 (03846), 12" double stud walls w cellulose, heating/cooling is single Mitsubishi 12k btu heat pump, 2 story, very open floor plan downstairs (and up). Blower door test done before insulation/sheetrock and came in at 0.67 ACH at 50 Pascal.

In Mechanicals | Asked By Brian Post | Jul 3 14
1 Answer

Can we replace fiberglass insulation with XPS?


We have a 33 year old townhouse that has a brick exterior on top of wood frame. There is fiberglass insulation in the wood frame, but we have lots of air leakage.

Would there be a problem with replacing all of the fiberglass insulation with XPS rigid insulation or spray foam insulation? If we did, would the XPS and or spray foam be an adequate air and vapor barrier?

Our goal is to reduce the air leakage and heat loss/need for air conditioning.

Thanks . . .


In Energy efficiency and durability | Asked By Phil Troy | Jul 3 14
8 Answers

Efficient basement dehumidification – how to?

Our deep energy retrofit of a 112 year old masonry building in Chicago includes a basement unit (garden apartment). The old foundation walls always draw some moisture and for that reason are exposed on the inside so that they can dry out. That works fine during fall, winter and spring, when the ERV removes that excess moisture. During summer, however, that moisture starts building up and I have a really hard time to control it.

In Energy efficiency and durability | Asked By Marcus de la fleur | Jun 25 14
4 Answers

Anyone have experience with Aeroseal duct sealing?

I'm considering developing a magazine article on Aeroseal duct sealing. This is a process where registers and diffusers are sealed with plastic and a vinyl based sealant is blown into the ducts. The sealant collects around leaks until they are ultimately closed off. The big advantage is it can seal ducts that are inaccessible for conventional sealing methods.

Here's more:

Patrick McCombe
Fine Homebuilding Magazine

In Mechanicals | Asked By Patrick McCombe | Feb 26 14
8 Answers

EPS as continuous insulation in above-grade, rainscreen cavity walls

We are building a house in Toronto, Canada. By code we need interior poly, so our walls need to dry to the exterior. The assembly is:

5/8" GWB
6 mil poly (vapour retarder)
2x6 wood studs @ 24" o/c w. R22 Roxul in the stud bays
1/2" plywood sheathing
Tyvek (drainage plane / air barrier)
1" continuous rigid insulation
1x4 PT wood strapping (fastened through rigid)
marine grade plywood or painted hardie board panels as cladding

In Green building techniques | Asked By wendy wisbrun | Jun 24 14
6 Answers

Looking for someone to design/build an energy-efficient home in Maine

I've contacted a few energy-efficient home designers/builders in the Cumberland County, Maine area to design/build a home for my family but they are backlogged with work for 6 mos-1 yr.

Can someone make some recommendations of quality energy-efficient home designers near Cumberland County, Maine and also quality builders of energy-efficient homes near Cumberland County, Maine?

In General questions | Asked By Eric Cyr | Jun 20 14
8 Answers

Confused on air and vapor barrier with vaulted ceiling

Hello, I've done a ton of reading here and in just general and I'm thoroughly confused on what I should do. I'm in the middle of building a two story addition off the back of my house in central Pennsylvania. I've used scissors trusses and have fully vented soffit with a ridge vent. I plan on using knotty pine 1x6 on the walls up to a chair rail and drywall to the ceiling and then the ceiling will be 1x6 knotty pine.

In Energy efficiency and durability | Asked By SCOTT KOONS | Jun 29 14
5 Answers

Transfer fans from hallway to bedrooms

I'm looking at a few different heating and cooling options for a (very) efficient two storey house with no basement. An option I like is using one ductless minisplit air handler per floor. Simple, inexpensive, fairly easy to size properly, pretty efficient.

In General questions | Asked By Graham Fisher | Jul 1 14
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