East of Lake Washington, construction may be getting a little greener.

Milibrandt Architects and developer Natural and Built Environments filed paperwork last week to build the first-ever “passive-house” project on the Eastside, a six-story, 109-unit apartment building in Redmond.

Yes, the name is cringeworthy. But green builders say passive-house construction holds big promise for radically reducing greenhouse gas emissions from homes.

The key to passive-house construction is that the design of the home does (almost) all of the work in cutting down on energy use.

A passive house is an airtight envelope, with plenty of insulation and systems to recapture and recycle excess heat. Solar panels may be part of the solution, to power limited heating and cooling systems, but more important are thick windows and walls, to cut down on heat loss.

All that enables energy savings of as much as 75% over traditional construction, according to the German Passivhaus Institut.

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Two multifamily passive-house dwellings already exist in Seattle, at 3700 Hudson St. in Columbia City, and at 208 25th Ave E. in Madison Valley. Two more are due on the market in the coming year. Local contractor Cascade Built is behind all four projects.

In Redmond, the anticipated passive-house project could be located at 8550 154th Ave. N.E. — if, that is, one hiccup is resolved: The current owners of the property haven’t yet agreed to sell.