The Reach Guesthouse combines Passive House performance with classic beauty

The Reach Guesthouse combines Passive House performance with classic beauty

Architect Jonathan Kearns shows that you can have it all.

When Americans loyal to the Crown moved north after the American Revolution, many settled in Prince Edward County, projecting into Lake Ontario just about 20 miles across the lake from the USA. Many of the houses they built became Ontario classics; small, square, efficient plans with steep roofs enclosing attic rooms on the second floor.
© Jonathan Kearns
Charming yes, but energy efficient they are not. So when architect Jonathan Kearns (of Kearns Mancini Architects) with partner Corrine Speigel wanted to renovate one to Passive House standards, they faced a number of challenges. Passive House is tough enough on new construction and extremely difficult on renovations, so the Passive House institute developed a special standard, EnerPHit, that certifies retrofits and allows slightly higher energy consumption that varies according to climate.
Lloyd Alter/CC BY 2.0
It probably would have been cheaper and quicker to start from scratch, but there is a charm and beauty to these old houses that Kearns wanted to preserve and expose. So he stripped the interior down to the wood structure and sandblasted it, creating a stunning, warm, wooden interior.
Jonathan Kearns still draws by hand!/CC BY 2.0
He then wrapped the whole house in a new house built of Structural Insulated Panels (SIPs). Kearns described it in Canadian Architect, listing the five key principles of Passive House design:

1) massively insulated, thermally broken airtight envelope. Lloyd Alter/ back of old house visible from new addition/CC BY 2.0 The original building was reduced to its barest hand-hewn wooden structure, meticulously cleaned, and then sealed inside 
an airtight skin. We then added a new jacket of R43eff Structural Insulated Panel (SIP) based insulation to the walls and roof. (The “eff” designates “effective” R-values of the wall assemblies as opposed to the suppliers’ nominal values per layer of material.) One of the many challenges was to get an airtight seal around the existing structure. To achieve this, we had to lift all ground level floorboards, insert an Oriented Strand Board (OSB) layer and then relay. We had to pry loose the old board-and-batten walls, working progressively around the building so that we could seal the floor to the air/vapour barrier wrapping the house. The front gable window was intentionally oversized to allow a glimpsing view of the original house within the new house.

2) Triple-glazed airtight, thermally broken windows. Lloyd Alter/ Dining room corner window/CC BY 2.0 Kearns notes that “in a Passive House, you can sit next to a window in the dead of winter and not feel a draft, and then sit next to that same window at the height of summer and not feel overheated.” That tells you something about the quality of the windows here in the kitchen addition; there is a lot of glass in that dining area. Lloyd Alter/ Old meets new/CC BY 2.0 In this image you can see the original house, and the window perched between it and the new SIP exterior.

3) Optimized orientation. Lloyd Alter/ view from northeast/CC BY 2.0 Here, Kearns is working with an existing house so he doesn’t have a lot of choice about orientation, but was careful with the big new windows to have them facing north and east, to minimize overheating.

4) Mechanical ventilation energy recovery Lloyd Alter/ heat recovery ventilator/CC BY 2.0 Here’s the big Heat Recovery Ventilator in the storage room. The round vents are the only new touches you see in the old wood walls.

5) Optimized functional design. Lloyd Alter/CC BY 2.0 This is where many Passive House designs go off the rails- It can be hard to make an optimized, functional design truly beautiful. It takes real skill and talent to make Passive House designs beautiful when you have limits on window size due to energy and cost, and have to minimize jogs and bumps that can create visual variety but also thermal bridges. Many Passive House architects are also data nerds, putting performance before beauty, or as Steve Mouzon would call it, lovability. That’s why some have problems with it; I often quote designer/ builder Michael Anschel:

Buildings should be designed around occupants. That's who they are for! They should be comfortable, full of light, grand or quaint, they should resonate with our souls. Passivhaus is a single metric ego driven enterprise that satisfies the architect's need for checking boxes, and the energy nerd's obsession with BTUs, but it fails the occupant.

Lloyd Alter/CC BY 2.0

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