A new model of modular housing for local authorities and developers

Chapman Taylor's Umbrellahaus model of offsite housing for cities

The debate for local authorities continues on whether to focus on retrofit for older housing or to build new to address the housing crisis and meet net zero goals. Existing housing contributes significantly to carbon emissions but so does the construction process when creating new homes.

Architects Chapman Taylor joined our 'Sustainable Cities' forum this month with West Midlands Combined Authority, Kier Group and planners David Lock Associates, to discuss its approach to meeting the housing crisis and climate change concerns through 'Umbrellahaus UK'

The practice says it has developed a sustainable, affordable, off-site housing model which can be constructed at scale and speed to provide much-needed housing for communities within towns and cities. Modules are scaled for easy transport to site, with off-site construction providing factory conditions and encouraging clean, energy-efficient and accurate assembly. The method of delivery produces high-quality lightweight, versatile construction which can be seamlessly integrated into the existing city fabric. Umbrellahaus housing modules range from one-bed to three-bed family units and provide a choice of homes to reflect peoples' ability to pay and the different stages of their lives. All unit sizes generally follow the London Plan space standards, which can be reduced in size where appropriate to match market demands.

Director Michael Swiszczowski told Future Cities Forum:

'We all have different tastes and lifestyles and need different types of housing. Retrofit absolutely forms part of debate on housing but not all of it. We need to design spaces for everyone's needs as one size doesn't fit all for our housing solutions in the UK.

'Consider the numbers, they are so vast. Potentially we need 50% from new build but maybe more, we shouldn't diminish it but beyond that we should be constantly asking ourselves how we can supplement that figure with more retrofit.

'You really need to understand the fabric of stock that you are dealing with. Is it better to add another 15 years onto older properties through retrofit if new build can last 100 years. Yes, carbon emissions are created on construction sites but then if you don't have to visit site again for 100 years it saves on emissions. More emissions are created with retrofit by having to go back every 15 years. Building fabric we know even from the 1990's isn't good enough. My view is we need to design for the long term, for 100 years.'

'Local authorities in the UK and overseas absolutely do want to embrace what we are doing. There is an element of talking through the process but they can see that there is a 90% saving on material wastage and improved energy performance. ' ' 'The biggest barrier to it is in looking at the factory process, making sure there is enough supply and it takes a lot more than 10 or 20 houses in each borough for it to be efficient. It needs to be joined up with central government supply to keep these factories moving. There are also land and planning issues, but the education process with authorities is going well. Everyone is keen to embrace it and the rental market has helped us with modular housing. With component parts we can create a range of different houses, all with different components but with apartments it has to be more standardised, so this needs a volumetric approach. It is important to understand peoples' perceptions but once we get over these, the reactions can be good.

' There is flexibility in the umbrella approach because you are giving people a choice to move within their community as they age and keep the location that is still important to them. We have written papers on what has happened to peoples' views on housing needs during the pandemic and how Covid has changed design. Post pandemic there is much more talk now on people moving back into city centres within an age demographic because they have missed the city centre lifestyle - it is no longer just a case of people wanting to move out to the suburbs for a big garden.

'It is important within planning to understand the finance involved. There are always aspirations in planning but you have to make sure these are delivered and this depend on how rigorous the cost planning is. A lot of this hasn't been done before in the sustainability area and is hard to price. Your price also has to be competitive. Everyone has different ideas on what sustainability means and it hasn't been done before. You have to ask the questions - do you mean heat pumps for example? Everyone has to understand exactly what features are being talked about. Ultimately though I don't want to sound negative, everyone one wants the same in the drive towards sustainability.'

Chapman Taylor notes that Umbrellahaus modules are thermally efficient, maximise daylight, minimise maintenance costs and encourage recycling. The firm is currently collaborating with a wide variety of stakeholders in order to establish an 'umbrellagroup' approach to bringing forward developments.