These are very common in Europe but new to North America. We need a lot more of them.
Accepted wisdom in North America is that the Passive House standard is just for houses, too expensive, and too hard. Many people ask, “Why bother when you can pop a solar panel on top and get Net Zero?” That accepted wisdom got challenged last year with the big House at Cornell Tech, and another kick was delivered with the recent opening of The Heights in Vancouver by Cornerstone Architects.
There’s a lot of accepted wisdom bashing going on here. It is built by a private developer, 8th Avenue Development Group, as rental housing. Developers don’t spend more money than they have to on rental housing, yet here they built 85 units of what they call housing for moderate-income households to Passive House standards. That was enough to get Mayor Gregor Robertson out for the opening. Robertson had a lot to do with the progressive policies that encouraged this development; it is a shame that he has decided not to run again.
There are a couple of reasons that developers might choose to build Passive House. According to Green Energy Futures, Scott Kennedy of Cornerstone told 8th Avenue that they could save $450,000 on mechanical systems and another $150,000 on natural gas if they built to a passive house standard. The insulation and windows cost a lot more in Passive House, but the bigger the building, the smaller proportion of exterior wall to floor area and the lower the overall cost impact.
The City helps promote Passive House, with its thicker walls, by giving little density bonuses that compensate for the thicker walls, because for developers, the lost square footage is more valuable than a bunch of extra insulation.
In rental housing the Developer usually pays most of the operating costs including energy for heating and cooling, so a big benefit of Passive House is that these are as much as 90 percent less than in conventional buildings. It may wall also need less maintenance; as the developer notes,
The building is a simple super insulated “dumb building”. No technology or complicated mechanical systems, just a simple envelope, high quality windows and high quality air control through Heat Recovery Ventilation. Walk in and set your heat……that’s it! The money is spent on its simple well-built design, not technology.
(It should be noted that the term “dumb building” was first used on TreeHugger four years ago and then in some presentations I have given at Passive House conferences; I am rather proud that it has become part of the lexicon.)
There is also a marketing edge in a competitive rental market;
- It is more comfortable as there are no cold spots;
- It is healthier; in many apartment buildings, the makeup air actually enters the apartment under the front door from the pressurized corridor, picking up whatever from the carpets and floor; in Passive House, there is a heat recovery ventilation system delivering fresh filtered air.
- It’s really quiet. It can’t answer for the guy partying upstairs, but you won’t hear anything from outside.
(You can read more about this in the PDF Developer’s guide to Passive House Buildings, based on the New York Passive House guide and modified by me)
The Heights is a mid-rise building built of wood, with 14 inch thick walls including rock wool insulation and 2 inches of polystyrene to wrap up any thermal bridges, totaling R40. The roof is R60.
It has been said by some that the Passive House standard is too rigid with its “one-size-fits all energy use limits, (well suited to Germany).” But R40 and R60 are not exactly extreme these days. Vancouver has a temperate climate and hits the numbers with less insulation than they might need in Montana. To paraphrase architect Elrond Burrell, if I want to be comfortable in Toronto in winter (my one-size-fits-all standard) I wear a thicker coat than I do when I visit Vancouver. The Passive House standard, like my clothing, changes according to climate. The colder the climate, the more expensive my coat and the thicker my mitts, but that seems totally logical to me.
Like many Passive House buildings, it has a very simple form; what Passive House architect Bronwyn Barry hashtags #BBB or “boxy but beautiful.” The challenge architects have is how to deal with the smaller than usual amount of glass and the lack of jogs and bumps that can add interest but are also thermal bridges and rain-catchers. Cornerstone has done a good job of busying up the facade with sun shading and Juliet balconies.
Scott Kennedy sent us some images of the interiors and even though it doesn’t have the usual floor to ceiling windows found in most apartments these days, it is still pretty bright and looks very comfortable indeed.
On 8th Avenue Developments’ website, they say their focus is “on well designed, sustainably built, comfortable living spaces using the latest in design approaches, technologies and processes.”
The Heights appears to be all of that — mid-rise, sort of affordable (this is Vancouver), built out of wood to the toughest energy standard, Passive House. We need a LOT more of this.