“The developed world’s wealthiest cities are facing housing crises so acute that not only low-income workers, but also the middle and creative classes, find them increasingly difficult places to afford.” Shaila Dewan, The New York Times Magazine

It would be hard to find a news or current affairs platform that isn’t currently running stories about the housing crisis, and a key part of that is affordability. Cities are trying to address this in various ways, such as by mandating a proportion of homes in new developments are sold as “affordable housing”. This could mean the sale price is capped at a percentage of standard market rates or that the residents must work for local essential services. Whilst helpful, such measures are arbitrary and can too easily be avoided or diluted.

But in this context “affordable” all too often means the houses are obviously inferior to their neighbours: rooms are designed to just comply with minimal space standards, the quality of fitout is poor, and they are built as a cluster (ghetto?) on the least attractive part of the site. There are cases where the children can’t even access the same shared play equipment. It seems the trade off for financial affordability is social capital.

In any case, the biggest impacts on the cost of new-build homes is nothing to do with construction costs. A study of residential development costs for houses, townhouses and low-rise apartments in Australia and New Zealand indicated materials and labour accounted for just 30-35% of the total. By comparison, land purchase and infrastructure costs were 32-34% while developers holding costs and profits and government taxes were 27-31%. In short, roughly two-thirds of what the homebuyer pays for a new-build are macro-economic, political and social issues which have nothing to do with the building.

But within that other third of the cost that we can control, how can we design and build homes in ways that make them more affordable.

1. Keep it simple

By keeping the building footprint to a simple rectilinear form we get the most internal space for the least external volume. Every corner in a wall costs more to build and uses more materials (as well as compromising the buildings insulation and energy efficiency). Same with the structural design, keep it simple, avoid structural gymnastics like large cantilevers. That doesn’t mean bland and boring, good architectural design can bring out the quality in even the simplest building.

2. Stick to mainstream supply chains

There are many strong arguments for using bespoke products or local traders but what the mass market does well is provide economies of scale and that is by far the biggest influence on construction costs. Just like any industry that makes stuff for the mass market, the housebuilding industry is based on repetition of standard details using a limited palette of materials which can be sourced from a diverse range of suppliers on an as-needs basis, whilst minimising waste and delivering the final product in the shortest practical timeframe. If the designer can find local and bespoke suppliers within that framework, all the better. (We do need to make sure sustainable products become the default and benefit from those same economies of scale, but that’s another story.)

3. Maximise useable space

Even if the total floor area is constrained make sure the layout can be used in flexible ways and that it maximises the perception of space. Keep the main living space as generous and open-plan as possible by minimising the number and size of separate rooms and avoiding long corridors. This also reduces the amount of internal walls needed, reducing the amount of materials used and further simplifying construction. I even recommend against built-in wardrobes (it’s cheaper to buy one from IKEA) and suggest a proper storeroom instead. Of course a balance needs to be struck between open and private spaces, but it’s relatively simple to subdivide space that already exists to meet evolving needs and in the meantime you can enjoy that greatest luxury: space.

4. Basic fitout

Our homes have become firmly embedded as part of modern consumer culture and the “Instagram age” so it has become the accepted norm to install high value kitchens and bathrooms. Building regulations only require essential cooking and sanitary facilities which could be provided at a fraction of the cost. In some European countries rental houses don’t have any fitted kitchen, the tenants expect to install their own (and take it with them when they leave). Would homebuyers be willing to trade down at the start of their tenure? Fittings can be upgraded and expanded in the future. Plumbing and electrical connections can be made in anticipation of that second bathroom. Similarly to the last item, this is about not paying now for things that could be could be done later.

5. Consider ongoing costs and value, not just construction costs

Don’t skimp on things that cannot be readily changed in the future, that will limit the value of the house, or that will compromise its performance. Using attic trusses for the roof mean you can easily convert the space into habitable rooms, where standard prefabricated trusses make it useless apart from storage. Installing quality external wall and roof cladding with a long term warranty will enhance the house resale value compared to cheaper products. Making the home as energy efficient as possible will reduce your bills, allowing more money to pay for the mortgage or save for future works.

6. Allow the owners to do some of the work

We have become used to buying only the finished product but in many cultures it is still accepted that the homebuyer will do some of the work themselves. At the extreme this is where only the external building envelope is completed by the builder, referred to as “skeleton build” with all the internal fitout left to the buyer. The Chilean architect Alejandro Aravena has developed the concept of “incremental housing” where he effectively builds only half a house with the essential services, leaving space the owners can later infil to create more rooms as their funds and needs dictate. Think of how many suburban garages have been converted into play rooms, granny flats or home yoga studios, the cars banished to the driveway.

We have to be careful about what we cut out. Applying blanket rules about reducing space standards will only hurt those that are already living with the minimum. Whilst the growing enthusiasm for micro-homes or capsule-apartments has thrown up lots of interesting designs these are only suitable as short term solutions for most people. But our houses were never meant to be fixed in time, we should expect them to grow and evolve as family needs change and finances become available. So why not plan to keep it very simple to start with, especially if that helps to lower the bar for housing affordability.