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9 Answers

Improving the airtightness of an average entry door

It's been cold this week, and I'm fighting drafts around my doors. Most doors have the same air sealing method, involving a foam kerf seal. It's an inexpensive and robust design. (Remember the Stanley magnetic seals?- those were tight, but made of conductive steel). http://www.homedepot.com/p/Frost-King-E-O-1-in-x-7-ft-Brown-Replacement-...

The problem is that the door is not held tightly enough against the seals. But if you use the deadbolt to hold it tight, the deadbolt can be difficult to operate, and it will wear out faster.

In Energy efficiency and durability | Asked By Kevin Dickson, MSME | Nov 17 14
2 Answers

Am I crazy or is the NIST house really confusing?

I was all excited to dig into the details of the NIST NZERTF. I was slowly moving away from SIPS and looking a lot at the PERSIST building method. I was reading articles on the building science center's site about the "perfect wall". All standard building science nerd stuff. Then I get onto the NIST site and click on the "centerfold", the Fire, Plumbing, Mechanical, and Electrical Plans PDF. I started scrolling though the pages and reading all of the details. What should have been a good time went south pretty quick. Looking at DHW I see a HPWH.

In General questions | Asked By Joseph Welker | Nov 18 14
3 Answers

My question is ice dam related. I am looking for a permanent solution.

I get ice dams near my gutters every year and would like a permanent solution. I am in the process of getting it air sealed and insulated but I have solid soffits with small vents about every 6 feet. s this enough ventilation and if not what can I do to make it right? Thanks in advance.

In General questions | Asked By al saccoach | Nov 15 14
2 Answers

Taping Zip Panel Seams

We have installed the Zip-R panels on our house, but the seams have not yet been taped.

With the cold weather here, there will be lots more days with the temperature below the minimum 20 degrees recommended.

The house is in climate zone 5. Some of the panels were installed in August, some just recently.

Do we need to get the seams tapped if we have a couple of days of warm temperatures now, or can we wait until the Spring to tape the joints before putting on the siding?

In General questions | Asked By James Kuszaj | Nov 18 14
1 Answer

Can a skylight ever be energy positive?


I'm curious as to whether skylights are always net losers, or if one could be favorable given the right conditions. In general they seem to be avoided due to the heat gain potential and nighttime loses.

In PassivHaus | Asked By Ryan Griffin | Nov 18 14
8 Answers

Options for temporary heat in MN winter

I'm interested in the opinions of builders and others regarding temporary heat during contruction. My southern MN home is enclosed, windows in, and exterior walls spray foamed. Not as air tight as it will be, but pretty tight nevertheless.

Options include:
1. electric resistance space heat - pros: convenient, no fumes cons: most costly option per BTU, safety concerns for unattended heaters
2. portable kerosene heaters - pros: have unit available cons: fumes (about choked me when used last Saturday), need to refill reservoir tank every 36hr

In Mechanicals | Asked By Kent Jeffery | Nov 18 14
8 Answers

Half insulating a stone basement?

It's been a long road and we are almost ready to move in to our project. I tackled the two part plaster myself with nice results but now it's getting cold. My basement is typical fieldstone 1880 style and the house is in Zone 6b. The foundation is about 4' underground and 2' exposed with a 10x10" fir sill plate beam. I have read the building science articles about completely modifying the basement but that's not in the cards and is another massively expensive project I cannot tackle at the moment.

In Energy efficiency and durability | Asked By Geoffrey Cook | Oct 31 14
3 Answers

Are tar paper and Tyvek a vapor trap?

Can you please set me straight because I am getting different points of view on this. My home is 40 years old, has the old type of sheathing, a layer of tar paper and then T1 11 siding. In patching one side of the house, I have put 1/2 inch foam board over the T1 11 and then Tyvek. Is this a vapor trap? If so, what part of it is?

Is the use of tar paper and then a layer of Tyvek on the outside of the T1 11 a vapor trap?

Is the use of rigid foam board a vapor trap?

Thanks so much!

In Green building techniques | Asked By CK North | Nov 16 14
8 Answers

Moisture in exterior wall

I have posted questions several times regarding my double wall assembly on a house that I am in the process of building in a very cold climate. At the present time, the drywall is being finished and my air exchange system is not yet running as I don't want the system on when there is a lot of dust. I am running a dehumidifier which is taking out a lot of moisture from the air but certainly not enough. I am heating with electric heaters, keeping the house around 64-70F. My humidity is ~50-60% as a result of the new construction and the mudding that is happening on the drywall.

In GBA Pro help | Asked By Matthew Michaud | Nov 17 14
2 Answers

ERV - where does the moisture go?

I understand the difference betwen an HRV and an ERV - that the HRV transfers heat between the incoming and outgoing air while an ERV transfers both heat and moisture. I am puzzled as to how, in a house with an ERV, the moisture generated by bathrooms, laundry, people, dogs etc actually leaves the building if it is transferred to the incoming airflow ? Also, what stops odors being transferred between outgoing and incoming air ? I haven't mentioned cooking because I'm assuming a range hood with its own make-up air will be used.


In Mechanicals | Asked By Peter Hastings | Nov 18 14
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