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8 Answers

Helping my insulation contractor make the right decisions. :)


Good insulation contractors around here are hard to find. A lot of people are doing the work without understanding many of the techniques shared on this site and others. I talked to the person I am considering for my new house and I think I could use your help in educating him a little.:)

1) Radiant barrier in attic

Asked By Norman Bunn | Nov 17 17
1 Answer

Radon vent

Can a Radon vent be tied, legally, into a plumbing vent or must it remain separate through the roof?

Asked By Jerry Liebler | Nov 17 17
8 Answers

Site built ventilation baffle moisture issue

I installed site built rigid foam ventilation baffles per GBA article http://www.greenbuildingadvisor.com/articles/dept/musings/site-built-ven...

Asked By Michael Prisco | Nov 17 17
7 Answers

condensation on windows

I am a HERS rater, back in the summer, i tested a house for a builder.
built about a year ago and lived in.
​they​ had a problem with condensation ​collecting​ on windows
windows face north, and air changes in house were 2.4ACH
they had one continuous fan that was not working
so they replaced this fan which is guest bath, off kitchen, near laundry.
this now is supposed to run at 60 cfm continuous.
They replaced a second fan in the master bath to run continuous at 50,
occupied at 100cfm. ​both on the main floor, there is no second floor,
but a finished walk out basement.

Asked By dwayne petko | Nov 17 17
8 Answers

Flashing Bottom of Window flange?

I've noticed that a lot of builders will omit taping over the bottom flange of a window once it has been installed. Sides are taped/flashed and the top flanged covered by WRB flap. Yet, bottom flange is left exposed.

I presume this is to allow water to drain from the assembly. But is this really necessary- especially if weep holes are left uncovered? Will this result in air leakage at the bottom of window?

Asked By Rick Evans | Nov 16 17
0 Answers

Cut & Cobble-3 season cabin

I have a 3 season cabin in (Zone 7) of northern Wisconsin. 2x6 walls 16" OC. The cabin is sheathed in OSB,

Exterior foam of 3" is not an option. The cabin is 20x26' and I plan to cut & cobble 2" XPS on a table saw and fill the cavity with fiberglass batts. Granted...this is time consuming....but there's no hurry. I realize this doesn't address thermal bridging. My concern is longevity with OSB in a northern climate & still being insulated. Yes...I will install a rainscreen if vinyl is not used for siding material.

Asked By Dan Musielski | Nov 17 17
2 Answers

Flat roof attic insulation

My home was built in the late 1890s and has a flat roof. It has aluminium siding and it has two floors and basement. On the second floor, we have sheetrock ceiling. There is an older plaster and lath ceiling on top of the sheetrock. There is about a foot of space between the ceiling sheetrock and plaster ceiling. In the attic, there’s no insulation at all. On the edges, you can see the stud cavities that run down to the second floor. You can only see down to the second floor and not the first floor. So not sure if it is called balloon framing.

Asked By michaeldrehl | Nov 17 17
6 Answers

Sizing Ductless Mini Split for HEATING

Hi all,

I'm going to install a ductless heat pump. I settled on LG Art Cool Premier (HYV1 or HYV2). Now I need to figure out system size, and there is too much info.

I have 550 sf addition built in late '80s, which is a split lever open space, and is VERY cold (i've attached some photos)!

It has a large french door (8x10' glass, 3 sections), 7 windows, and 5 skylights. All are double glass.

Asked By Levab | Nov 16 17
6 Answers

Ranch vs 2-Story Home

Generally speaking, if one is looking to build a 1,600 sqft home, which provides the better energy efficiency and less expensive route?

Having 2 levels of 800 sqft each seems like it would be better from an energy standpoint since there is less roof area and everything is compacted in a smaller pad. Cost wise there is less roof area to frame, insulate and install a roof on with a 2-story. There is probably some cost savings in flatwork and foundation with a 2-story since the footprint is smaller.

Asked By Peter L | Nov 16 17
17 Answers

Residential frost-protected shallow foundation in central Mass.

We are planning to provide a monolithic pour frost-protected shallow foundation (FPSF) for a single story 1300 sq ft 2 bedroom home in central MA. Air Freezing Index is 2000. I have read through many different case studies, research papers, codes, etc and there is a bit of conflicting and locale-specific info so I am looking to see whether I understand what is required here. I am a newbie owner-builder. Any constructive criticism would be appreciated, but I don't want to foment any religious wars.

Asked By Kenneth Gartner | Sep 2 16
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