What is a Passive House?

While building uber-efficient airtight homes sounds a little obsessive, it’s actually become the “right thing to do” and the next milestone for many designers/builders in Seattle and around the globe. Better known as Passivhaus in Europe, the Passive House building standard is one of the most rigorous in the world when it comes to energy efficiency, yet it’s catching on like wildfire because it makes so much sense.

While it’s not likely we’ll all be living in passive houses any time soon, understanding the basic concept will make you stop and wonder why we haven’t been building homes like this all along. Check out this 90 second video!

Picture this! A modern, comfortable house with no cold drafts from unknown places in the winter, no sweltering rooms in the summer, no temperature variations from room to room, no need to close the blinds to prevent all your body heat from being sucked out the windows, and virtually no heating or cooling bills. Well, that’s a Passive House folks! And, the coolest part is they can be built in any climate or geographical region, and stay at a comfortable temperature year round with minimal energy inputs.

The prescription for achieving this level of comfort in a house (or any building for that matter!), without using expensive “active” technologies like photovoltaics or solar hot water systems, is relatively straight-forward (watch the video).

  • Super-insulated
  • No thermal bridges
  • Airtight envelope
  • Energy- or heat-recovery ventilation
  • High-performance windows and doors
  • Efficient systems
  • Passive solar and internal-heat gains

The result? “All heating needs in a typical Passive House can be met by a heater the size of a hair dryer. Heat from people, lights, appliances and the sun does the rest.” Mastering these principles and getting a project Passive House certified is not for the feint of heart though, which is why we’re lucky to have a growing number of architects, builders and consultants in Seattle with Passive House expertise. Their projects include:


Park Passive in Madison Park
Designed by NK Architects, built by Sloan Ritchie of Cascade Built, and with the assistance of Passive House Consultant Rob Harrison, this became the 1st certified Passive House in Seattle.
Now home to the Ritchie family!

Ballard Passive House

Ballard Passive House
Designed by VELOCIPEDE architects and built by Hammer & Hand in 2013.


Courtland Place Passive House in South Seattle
Designed & Built by Passive House Consultant/Builder Dan Whitmore in 2012,
this was the first project to be built to Passive House standards in Seattle.

Recent Passive House News
City’s first certified passive house is also a fun family home – Seattle Times, May 9th 2014
Passive House: The House of the Future – Huffington Post, May 7th 2014
Designing a passive house for Seattle that’s ‘resourceful, replicable and beautiful’ – MNN, April 23rd 2014

Seattle Green Builder Spotlight: Cascade Built

Cascade Built has been constructing high performance custom homes in Seattle for some time now, and they have a particular knack for maximizing the potential of postage stamp-size infill lots in the Madison Valley area. While many green builders make their way from ‘light’ to ‘deep’ green slowly over time, founder Sloan Ritchie has jumped in with both feet, and is seemingly only content when he’s literally pushing the green building envelope.

This is particularly refreshing when you consider that a number of Cascade Built’s most successful projects have been spec-built. We’ve had the privilege of working with founder Sloan Ritchie to market and sell a few of the more recent projects, and they’ve been crowd-pleasers every time! Clean modern designs that are at the same time warm and inviting, fresh and sassy finishes with earthy undertones, uniquely appealing color combinations that are both bold and subtle, and a predilection for open, light-filled spaces that connect to the natural and urban environment alike.

AlleyHouseAlley House – 3BR | 2.5BA | 1,830sf | Off-Street Parking
As one of the first LEED Platinum certified single-family homes in Seattle, this stunning modern redefined urban infill development with it’s plethora of sustainable and energy efficient features and unique back alley location. Structural insulated panel (SIP) construction, cedar rain screen siding, concrete and recycled wood floors, custom Kirei doors, dual-flush toilets, pre-wiring for photovoltaics and solar hot water, drainwater heat recovery, Alley House Kitchenrain gardens, grasscrete parking, a green roof and so much more!

Every square inch of this 3-story home was maximized, yet it felt both open and inviting with its over-sized windows and glass doors connecting the main living space to a private bamboo courtyard. The home’s high performance design and construction also meant it was 50% more efficient than other similar code built homes, and roughly 70% more efficient than the average Seattle home.

Alley House 2
– 3BR | 2BA | 1,697sf | 1-Car Garage

ExteriorflyerDesigned by award-winning architect David Foster and certified LEED Platinum, Cascade Built’s second Alley House was prefabricated in modular components by Seattle-based, green prefab specialists Method Homes. Sloan chose a modular prefab build for this project because of the shorter building time-frame (approximately 2 months) and reduction in material waste (minimized to less than 5%). The prefab build also means the house was constructed in a closed environment where exposure to elements such as rain, do not exist. All the modules were craned into place in one day!

PrefabKitchenThis 3-story home featured hardi-panel rainscreen siding, bamboo floors, custom Squak Mountain countertops, Energy Star and Water Sense fixtures and appliances, an on-demand tankless hot water heater, ductless mini-split heat pumps, heat recovery ventilation, and a fully conditioned garage for future ADU conversion.

If you think living in an alley sounds unappealing, think again! Tree-top views of Madison Valley, over-sized east and south facing windows for ample natural daylight, two entertaining balconies, and a quick stroll to neighborhood amenities made this the perfect urban retreat.

Park Passive
– 4BR | 3BA | 2,300sf | 1-Car Garage
Designed by NK Architects this ultra-modern home is now under construction in Madison Park and is targeting Passive House certification (the world’s leading standard in energy efficient construction). As a result of extreme attention to detail in air sealing, high levels of insulation, and high-performance windows, this home’s heating energy consumption will be reduced by nearly 90%.

This home will also feature a solar hot water system, site harvested woodwork, zero VOC finishes, heat recovery ventilation, pre-wiring for solar PV and more. True to Cascade Built style, the in-fill city lot this home occupies measures just about 2,000sf. This home is expected to be completed this spring, so stay tuned for our upcoming tour announcement!

Cascade Built also has a fantastic line-up of sustainably designed backyard dwellings – see Backyard Boxes to learn more!