Prefab Passivhaus CLT Tiny Homes being built in Britain
Did I miss anything? This really hits all the right buttons.
There are a few basic premises that drive a lot of TreeHugger stories about building:
- That prefabrication is the answer to building quality housing in quantity;
- That the Passivhaus standard is a great way to build energy-efficient and comfortable housing;
- That Cross-Laminated Timber (CLT) is the carbon-sequestering material of the future;
- That building smaller spaces will keep prices down and make housing more accessible.
Now British housing association RHP has built a prototype of a new housing unit that is all of the above. The "launch pod" is designed by architects Wimshurst Peleritti and is built in Legal and General Modular's new factory in Leeds, which Patrick Collinson describes in the Guardian as "revolutionary, and highly secretive." It is also a bit odd, because L&G is an insurance company, not a builder. Collinson writes:
It is an extraordinary move by L&G, better known as a car and home insurer, which if successful will catapault it into the top league of Britain’s housebuilders, albeit using a Ford-style production line.
The 280-square foot prototype is standing alone, but it would be built as part of a larger product that includes a range of unit types. The small area keeps the price down. The architects explain that "RHP will be using the homes to break into the intermediate market – helping the growing group of people who don’t qualify for social housing but are priced out of the private market." Unlike many small units, like those in Graham Hill's LifeEdited apartment or New York City's Carmel Place, they keep it relatively simple. Like Peter Kostelov's New York apartment, it has a separate bedroom. The architects explain:
The clever use of space means that the homes can incorporate many of the features of a much larger flat with the space being made to work hard. Key priorities included dedicated space for cooking, eating, sleeping, washing, and studying or work, as well as to store essential items and to have visitors during the day, evening or to stay overnight. RHP were adamant throughout the R&D process that they did not want to use space-saving gimmicks such as fold-down beds that are maintenance heavy and typically associated with small spaces. Their aim throughout was to provide high quality accommodation that did not compromise on quality or the feeling of space.
Collinson of the Guardian worries about the size of the units (which are smaller than the minimum UK standard) but quotes the RHP development director, Robin Oliver:
It has been priced for a single person, and we wouldn’t expect a couple to live in the space. We’re not saying this is going to be the new norm – we see people renting it for six months to two years, then moving out as they have saved for a deposit. A lot of our own employees pay more than £600 a month for a room in a shared house. The most common question we are getting from them, is ‘how can I get one?’
© L&G Factory
L&G has made a big investment in CLT modular, and have a big vision:
Building homes that are great places to live and good for our planet is at the heart of everything we at Legal & General Modular do. Our cross laminated timber homes use less energy to build and use less energy to keep warm.
Interestingly, we have discussed in a few previous posts the question of whether it makes sense to build modular housing out of CLT, where the entire wall is already one piece. I have suggested before that "CLT goes together so easily that it doesn't make a lot of sense to ship it as a prefabricated box." Clearly the people at L&G don't agree, and want to get as much of the job done in the factory as they can. (Watch a video of the steps in the process here, where CLT goes in one end and a finished module goes out the other. Note how at the end the exterior finishes are done on site, which avoids a lot of problems.)
Standard home types are built on site by hand. Some are built by craftsmen at the peak of their trade, some are built on Friday afternoons. Some are built with quality materials, some are not. Some are being constantly repaired and require re-work. Sound familiar? Imagine a home built in controlled factory conditions by fully trained and highly skilled labour, using computer control and materials and components selected as best-in-class, with every home produced being defect free.
This very true. The quality of much of British new-build housing is terrible, and likely to get worse if Brexit goes through and foreign workers have to leave. According to building consultant Mark Farmer, quoted in the Economist, about 15 percent of construction workers nationwide, and getting on for half in London, are foreign-born. “Brexit is the very last thing we need in an industry struggling for long-term manpower.”
It's also more environmentally friendly;
- Our homes adopt a fabric-first approach and are highly energy efficient, and can even be built to Passivhaus. A family living in a 70m² Passivhaus home, equivalent to a typical two-bed flat, could expect to pay as little as £25 on gas central heating each year.
- Our homes will be built of a material that stores carbon rather than emitting carbon when it is used -- timber. We’re not just using 2x4s; we’re using an extremely strong engineered timber product called Cross Laminated Timber (CLT). Our construction techniques mean we use less concrete foundations, making a quicker, cheaper and easier build.
Really, this is the kind of project that could solve so many problems. It is not a monoculture of tiny units but is a mix of types (video above shows a two bedroom, two storey version). It is built to what could be called "missing middle" densities that can accommodate a lot of people. It consumes almost no energy and is built of the greenest materials. The factory can crank out 3,500 units per year; I hope they do ten times that.
Small, affordable, green, sustainable multifamily housing. This is exactly what we need just about everywhere. Nice work by Wimshurst Pelleriti.
UPDATE: A reader asks "What is the benefit of brick cladding on site? This would seem to be totally against the ethos of off-site construction. " I try to explain in Mind the gap: Should modular builders do the cladding in the factory or on site?