Community: PassivHaus

PassivHaus is a standard of construction that yields extremely tight envelopes and low energy use.

The PassivHaus Institute is in Germany, but we have a branch here in North America as well, Passive House Institute US

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0 Answers

Free webinar today - Prefab PassiveHouse construction

I'm not affiliated with the following, but thought it might be of interest to many readers here.

Passive Buildings Canada is offering a free webinar this afternoon discussing prefabricated Passive house construction.
Adam Cohen
Lydia Hunter
Hans Eich

Follow the link here for registration - Fri, Apr 24, 2015 3:00 PM - 4:30 PM EDT

Asked By Mark Fredericks | Apr 24 15
27 Answers

Sizing minisplits for adequate heating & cooling in a cold-climate Passive House

We are building a 2300 square foot Passive House in the midcoast area of Maine and are having trouble choosing and properly sizing our mini splits for both adequate heating and cooling. We live in an area where of course it gets below zero many times during the winter. So we are limited (I think) to the brand of mini-split we can choose from.

Asked By CathrynJones | Apr 11 15
9 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

Asked By Gerald Blycker | Nov 21 14
2 Answers

U-values of solid walls

I asked a GSHP installer how they could work out heat loss for each room without knowing the construction characteristics of the walls, roof and floors and received the following answer "our technical design team have worked out based on building regulations the required U-value’s for different properties be it a new build, renovation or boiler replacement in an existing house"

Is this a case where common sense has failed me, can they do this with any degree of accuracy or am I right to be suspicious of the results their averages produce?

Asked By George Winkle | Mar 19 15
11 Answers

What is the best sealant to use for airsealing?

I know I want seal as many air paths as possible. Is there one particular sealant that works best for things like drywall to studs, spaces between double studs, rigid foam to studs and PE film?

Asked By Donald Lintner | Jul 28 09
7 Answers

I keep seeing descriptions of Passivhaus buildings using 90% less heat

But what does this equate in in btus at peak load or kWh/yr?
I know this is a broad question thats different in every climate but i just want some numbers for context, so lets compare two code minimum houses @1000sq/ft, one in climate zone 5 with 4000HDD and the other in climate zone 6 at 5000HDD compared to two identical location passivhaus'
For the sake of argument lets say both buildings have a design temp of -25C


Can these numbers scale with size (would they double at 2000sq/ft or be half at 500 sq/ft?

Asked By Alan B | Feb 14 15
7 Answers

Euro style inswing windows & lessons learned

This is kind of an interior design question, but I am wondering what people's experience has been with these inswing windows? Specifically in living rooms and bedrooms wherein the inswing of the window can cause problems with furniture placement.

I am tempted to place windows at 36" high in living room/bedroom areas simply due to ease of furniture placement. If it's that high (and wider to compensate), it won't ever hit the back of a sofa or end table or whatever. Ditto for bedroom furniture such as a nightstand, desk, or dresser.

Any lessons learned would be appreciated.

Asked By Lisa O'Donnell | Jan 5 14
2 Answers

Hybrid heat-pump hot water heater cooling effects

We have a GE hybrid heat pump hot water heater in the non-partitioned 1100 square foot basement of our pre-certified PassivHaus home in northern NJ.

We've found that when it's operating as a heat pump, it exhausts enough cold air that it actually cools the basement significantly.

Asked By Len Moskowitz | Dec 31 14
3 Answers

Santa, Please Bring me a Balanced ERV...

We’re getting into commissioning residential heat recovery ventilation systems (balance* and optimize**) and so recently invested in a Dutch-made balometer that is really accurate*** for measuring low air flows. What was once done crudely with a Pitot tube and unglamorously with a garbage bag "should" now be able to be done quickly, simply and repeatably with more accuracy – perhaps too much - which may be part of the problem.

Generally, the procedure goes like this:

1- balance the adjustable dampers (if present) with the system at max speed

Asked By Greg Labbe | Dec 29 14
2 Answers

Additional insulation below laminated/floating floor over rigid-foam-insulated concrete slab?

I have a 4" concrete slab insulated with 4" of rigid foam (on the underside, of course). I was planning to install laminated floating floor on top of everything. As I have to install 2x2"s over the concrete in order to hold the laminated floor, a friend suggested to fill the space between the 2x2"s with insulation or, at least, dirt.

The questions are:

Asked By Jose Castro | Dec 27 14
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