After several months of creativity, diligence and perseverance by the homeowners and The Artisans Group, we recently broke ground on what is the second Passive House built in Washington State!
Do you need a quick Passive House refresher? [Click here].
The home is being constructed in the eclectic Northeast neighborhood of Olympia. The homeowners currently occupy an existing older home on the lot, which will be deconstructed once the new home is ready for occupancy. The new home is a 2300 s.f. custom home sporting traditional forms, but has an understated and modern austerity, which makes it timeless and really cool! Inside is a vaulted, loft style great room on the main floor with un-obvious but careful attention to aging in place principles, such as wide halls and easy traffic patterns.
To meet certification requirements, the project performs (pending) to the Passive House standard of a specific heat demand of 4.75 Kbtu’s and a primary energy demand under 38 Kbtu’s per square footage of treated floor area (1902 s.f.). It will also meet the required .6 air changes per hour at 50 pascals. Consequently, this means the house is so efficient it can be heated with the same energy it takes to run a hairdryer! How do we determine energy performance? [Click here].
The energy use of a Passive House is unbelievably low which has caught the eye of the Washington State University Energy Extension Program. They have asked to use this house for a special pilot project where they will collect and analyze energy-use data. We’ll be sure to post any results once they are available.
Below is a picture of the ground prep prior to pouring the slab. It was very critical to get the pour just right as the finish concrete will be the finish flooring.
Critical attention is given to any penetrations within the slab. In a Passive House, managing all ‘holes’ in the envelop are paramount to the success of achieving the performance criteria. Here is a waste tube sealed with a special adhesive made in Switzerland for the purpose of sealing Passive Houses.
Because the envelope is so tight, to address indoor air quality, this home has an Energy Recovery Ventilator (ERV), the Ultimate Air Recuperator, which constantly delivers filtered fresh air while recovering the heat from outgoing stale air for continued indoor use. The heating requirement for the residence is so low that a small 1000 watt electric heating coil incorporated in the ERV is the only heat source, that’s smaller than most hairdryers! Due to the constant filtration and amount of fresh air in a Passive House the indoor air quality is exceptionally high. The last piece of the ‘mechanicals’ is a natural gas driven instant hot water heater, the Navien. The house is pre-plumbed and wired for both solar thermal and solar electric panels.
But, I’m getting ahead of myself… we’ll keep you posted as the project progresses…With luck, we may even get the homeowner to blog about their experiences during this exciting project!
Stay tuned.
Posted on September 13, 2010