Modern methods of construction (MMC) are a hot topic in housing, and something for housing associations of all sizes to consider when undertaking development projects and looking to build more homes.
Jon Hobbs, Head of Development, Vale of Aylesbury Housing Trust
21 November 2019
I still contend that the supply of land, with viable planning consent, is the main protagonist of the housing crisis, but the techniques we use in construction can help to alleviate it. So if MMC will cure what ails us, or at least help, can they work for small and medium-sized housing associations? Yes, providing we understand the basics:
- Go MMC early on in a project. Don’t get a scheme through planning and then decide to use MMC. Carefully select a system that is right for your project and work with this from the beginning. This approach will give you the greatest choice and simplicity.
- MMC systems tend to be of lightweight construction, so pick one you consider robust or repairable enough for your needs. If you’re building property to rent it could be yours for 100 years or more and they do vary considerably.
- If you’re new to MMC you may find a turn-key contract, where the MMC supplier does all the work, reassuring. Although it may be cheaper to let separate contracts, the foundations can be complicated, and what if your MMC doesn’t fit when it arrives? Be aware also that if you nominate a supplier within a larger building contract and they deliver late, you could foot a bill for loss and expense.
- Components built in a dry warehouse should be consistently good but some MMC require considerable on-site work as well. MMC systems offer modern levels of energy efficiency, but these vary from Passivhaus standards to just OK – so do your homework and compare various products.
- The MMC suppliers are experts but are there to sell their product and are unlikely to highlight risks or problems within their pitch. Though these systems are becoming established there is still a learning curve and you will be an ‘early adopter’ at this point. Suppliers typically state that costs are no lower than traditional construction and highlight the time saved on site. In my limited experience it costs a bit more, so allow for around a 10-15% increase. The National Housing Federation supports a programme called Building Better, which is studying project costs and has more information.
- Insolvency is always a risk, but with MMC it’s a real showstopper. It’s not easy to get any part-finished project completed, but how about one using a bespoke system? Check, check and check again before taking the plunge. Also, consider what and when you are expected to pay during the process. Suppliers need paying, but is cost overly frontloaded before your product gets to site?
- Most of the popular MMC systems are timber-based so satisfy yourself regarding fire performance and the effect of moisture ingress. They are not unsafe, but housing associations now have new concerns over timber so make sure you satisfy your organisation’s requirements.
- If you want MMC but you’re worried about getting a structural warranty, don’t. The BOPAS accreditation scheme can help here and most suppliers have tie-ins with warranty providers. The National House Building Council and others are now actively engaging with the MMC sector.
- Finally, as with most things, knowledge is power and forewarned is forearmed. Independent advice is gold dust. It is worth talking to housing associations or contractors who have used MMC. The Building Better programme is currently developing some ‘lessons learned’ from current pilot sites.