Altair Ecovillage Discussion Group: Passive House

Sunday, March 15, 2020
3:30 pm to 5:00 pm
Kimberton Ecovillage Site – 2237 Kimberton Rd., Kimberton PA

Park at the Prizer Road parking lot
On Tuesday, Feb 18th, we toured Silvergreen in Bryn Athyn. Come to our Discussion Group to discuss the Passive House Institute US (PHIUS) national conference highlights and meet the project manager and builder of the Silvergreen project.
The 14th Annual Passive House Conference was truly inspiring!

Here are some highlights of the national conference
in Washington, D.C.:

Jeremy Rifkin’s The New Green Deal
The esthetics and design of the Passive House
Technical aspects of the systems
Environmentally-friendly breakthroughs
Panelization, Factory-built options
Marketing and mortgages

For our second feature, we will review our look at a local Passive House with Architect Ilsa Cassidy who did the energy model for the house, and Steve Hessler, who is with the builder and represents the building system manufacturer.

Here is what our tour guide Steve Hessler says about the project:
Silvergreen is a 10,000 sf combined single family home + caretakers dwelling using a Holzraum System Core* and shell over ICF foundation.
The project will be passive house certified, vapor open and foam free constructed from the foundation up.

Once the foundation was completed the entire structure was erected, closed in, insulated in approximately 4 to 5 weeks (except for the the blown in insulation above the ceiling membrane and service cavity which will be installed next month) The basement level windows and exterior doors which will be site installed are due to be set in a few weeks.

The windows and exterior doors are Zola triple pane wood frames with alum cladding.

The panels come delivered with a SIga self-adhered vapor open membrane as an additional assurance that water infiltration at the insulated wall panels does not occur during or after erection.

These 2×8 /cellulose + Steico wood fiber insulated wall panels dry at least 4 times faster than code compliant or foam clad wall systems. While foam clad wall systems by design attempt to block all seasonal and operational vapor transmission (that is normal to any structure), instead the Holzraum System envelope manages this moisture allowing hygric buffering and accelerated drying to eliminate any risk of mold that can easily occur in airtight buildings.

In addition, the 60 mm Steico wood fiber exterior insulation is far denser that foam or mineral wool materials providing additional thermal protection (through phase shift) against summer mid-day overheating. Essentially, the wood fiber’s high density lengthens the time it takes for extreme high exterior temperatures to make their way through the walls.

Combined with the benefits of passive house airtightness and ERV delivered 24 hour filtered ventilation with heat exchange, the moisture management and thermal performance of the Holzraum System envelope insure a level of health and comfort that are very difficult to match with other approaches.

Hugh Lofting Timber Framing was responsible for coordinating thermal bridge free concrete scopes, 3d modeling to insure seamless coordination between the vaulted ceiling system and the roof truss system as well as all installation and coordination of the Holzraum System core and shell.

Extensive exterior timber frame details – the final touch – are due to be installed in three weeks.
*Here is a link to the Holzraum website: https://www.holzraumsystem.com.
Come to our site at 3:00 for a tour – please RSVP if you would like to join us. Bring a potluck dish to share for a meal after our Discussion around 5:15 pm. Contact Joel at 610-220-6172 or altairecovillage@gmail.com.