Madrona Seattle Passive House Siding

We are finishing up a very nice custom home passive house siding project in the Madrona neighborhood of Seattle.  If you’re unfamiliar with what a passive house is you can educate yourself here https://www.phnw.org/ .  The basic principle of these houses is that they are extremely energy efficient and offer an ideal environment for habitation.  On this particular passive house siding project the owners made the decision to use FSC certified cedar for the siding and exterior trims.  More information on FSC certified lumber can be found here https://ca.fsc.org/index.htm .   Using FSC lumber requires paying a premium and in our case was about 30% more in material cost.  We had our FSC tight knot cedar milled to a 1×6 flush fit tongue and groove.  Since the siding was designed to be put up vertically a grid of furring battens was constructed to allow for vertical orientation of the siding boards while maintaining the rain-screen drain plane.  The

methodology used for the exterior of the home was:  Zip wall system for the exterior sheathing.  More info on the zip wall system can be found here https://www.huberwood.com/zipsystem/home-zip-system.  The zip wall was sealed and waterproofed with  a liquid applied membrane and all the metal

flashings integrated.  Then rock wool insulation was installed on top of the sheathing and held in place by the vertical rain screen siding battens.  Another horizontal layer of battens was installed to allow for vertical siding installation.  The result is a super insulated wall system with a ventilated facade that will maintain its beauty

and performance for years to come.  With all the technical aspects and the environmentally conscientiousness of the project aside the end result is really stunning.  The rough sawn tounge and groove siding makes

the house look as if it were carved from a very large tree.  We think it looks great and are happy to have been a part of this passive house siding project.