Which Building Should Win the UK Passivhaus Trust Large Project Award?

Because of its silly English name, Passive House, many people think that the certification system is just for houses. But just as they are not really passive, they are not limited to houses; the original German name is Passivhaus and haus means building. After writing about the shortlist for the UK Passivhaus Trust small projects, readers suggested that we look at the large projects too.

Two of the projects are multifamily buildings that would be impossible to build in North America because they have single stairs, rather than the two that are required in almost all North American buildings. This is often controversial for North American readers–see Michael Eliason's Case for more single stair buildings in the US–but single stairs give designers a lot more flexibility, particularly with smaller buildings.

Agar Grove Phase 1A

Agar Grove Phase 1A doesn't roll off the tongue as a memorable building name, but the team behind it is memorable indeed; there's the talented Hawkins/Brown, architects who did a stunning swimming pool and worked on a plug-in CIty. They are working with Architype, who designed what I have called perhaps the world's greenest building. Then there is the brilliant engineering firm Max Fordham (the person Max Fordham lives in a lovely Passive House). That is certainly a prize-winning team.

What's interesting to a North American eye is that it is a slab building that could have had a center corridor and two stairs, but they chose to break it into two buildings on a podium, each with their own more intimate common area. I like what Michelle Christensen of the building owner Camden Council had to say:

"We are determined to tackle fuel poverty and reduce CO₂ without the need for complex energy systems with high lifetime costs. The Passivhaus approach provides thermal comfort and air quality in a way that alternatives do not match. Although this can increase the initial capital costs, Camden Council – as both developer and landlord – believes that it will see the benefits of this approach, in higher build quality and reduced maintenance costs over the lifetime of the buildings."

Given the skill sets of Hawkins/Brown and Architype, it is disappointing that the building is concrete and not mass timber. But building codes changed after the Grenfell disaster and it was probably a tough sell for a social housing project. But it is still lovely; read more at the Passivhaus Trust.

Seaton Beach

I love how one of the questions that the Passivhaus Trust asks is what are the lessons learned from the project, and the first answer for this one is “Curves cost money” so simplify the design on the next scheme to lower the build cost.

Besides curves, Seaton Beach is Passivhaus, "Secured by design, and most ideologies of “lifetime homes criteria” were incorporated in the design. Finally, our desire was for healthy homes for owners to live in, so we followed the German Institut für Baubiologie (IBN) for principles of Healthy Building." The wiring circuits of the bedrooms are designed to provide an “electromagnetic field (EMF) free zone” around the beds to aid sleep quality for all occupants. The developers write:

"The project’s aim was to provide high-end, ecologically friendly apartments in a town looking to continue the green shoots of regeneration. We wanted to create a difference in the street scene and an iconic legacy building to let everyone know that Seaton is now “open for investment”.

Real estate development is challenging, especially for smaller buildings. Developers tend to try and cut costs, especially for things that people cannot see and might not understand, like Passivhaus standards and certification, which is why you get granite counters in leaky buildings. Not at Seaton Beach; builder Mike Webb concludes: "Whilst we could have made a little more money here, we didn't; we sacrificed a little bit of margin for the environment, but I think it's the right thing to do." Read more at Passivhaus Trust.

Cranmer Road

I once visited a Rhodes Scholar friend at Oxford and was colder than I have ever been in Canada, two days with no central heat in a 17th-century dormitory. I thought this was a rite of passage, but in Cambridge, students get to stay in a Passivhaus dorm where you never get cold.

The project, designed by Allies & Morrison with Max Fordham as Passivhaus consultant, is actually two buildings, one sort of historicist to address adjacent Arts and Crafts villas, the other modern. "This scheme reinforces that Passivhaus projects can come in various shapes and sizes. The site allows favourable building orientation with the primary façades facing north or south to optimise solar gains with projecting horizontal shades over windows."

My favorite statement: "As far as possible, the team tried not to innovate on the project and opted for conventional UK construction materials." They then say that it is made from CLT, which apparently is no longer innovative. Gwlym Still of Max Fordham, the Passivhaus leader, notes:

"The College has a history of high-quality architecture, and the Cranmer Road student accommodation lives up to these standards. Using timber as the primary structure helped to limit the scheme's embodied carbon, while operational energy is kept low through Passivhaus. Electricity is the sole fuel source, which works well with the ongoing decarbonisation of the UK electricity grid."

Read more at Passivhaus Trust

And Our Vote Goes To....

Having been a real estate developer in a previous life, I am really impressed with Seaton Beach. It's really hard to control costs in a small building; what looks like a comfortable margin can disappear in a flash, It is the rare customer who is willing to pay more for healthy or green building, So Mike Webb and his team deserve a lot of praise for pulling this off.

However, since I was in architecture school I have admired so much of Britain's social housing, doing a pilgrimage to the Smithson's late and lamented Robin Hood Gardens. A reader today complained that I "would prefer that we all surrender to socialism, and then join a commune and be issued a commune owed bike and all share alike?" Frankly, that didn't sound so bad, especially if it is in a Passivhaus building designed by some of the most talented architects and engineers in the world, let alone the country. If this is socialism, gimme more.

Agar Grove Phase 1A (Please, give it a better name!) is a model of the kind of housing that we should be building everywhere, to end energy poverty, reduce CO2 emissions, to give people a decent place to live. In this competition, I believe it is a clear winner.