Retrofit or rebuild as the building rules change
In June, the government changed the timetable for commercial buildings. The interim EPC C milestone planned for 2027 was dropped. Instead, privately rented non-domestic buildings over 1,000 square metres in England and Wales will need to reach EPC B from 2031, where it is cost effective to do so.
It would be easy to read that as breathing space. I would urge building owners to read it differently. Five years is roughly one refurbishment cycle, and it is shorter than many of the commercial leases being signed today.
Earlier this year the British Property Federation found that 81 per cent of commercial buildings across seven major English cities sit below EPC B. That is a great deal of stock to improve in a short window, and the designers, contractors and integrators needed to do the work will only get busier as 2031 approaches.
New building work has its own clock. The Future Homes and Buildings Standards, which update Part L, come into force on 24 March 2027. They raise expectations on fabric, low carbon heating, lighting and heat recovery for new non-domestic buildings.
Conversations with owners and consultants has moved on. Most accept that something needs to happen. What they want to know is how far to go.
Partial makeover or complete transformation
That question came up again and again on our stand at the Smart Buildings Show at ExCeL earlier this month. One camp argues for a complete transformation, stripping a building back and redesigning it around net zero. The other favours a partial makeover, taking the quickest wins first and spreading the cost.
Both have merit, and the right answer really depends on the building. Where the fabric is failing or the main plant is at the end of its life, a deeper refit may well be justified. For a great many buildings, though, the plant is sound and the real problem is how it is run.
Heating and cooling work against each other across zones, lights stay on in empty rooms and nobody can say with confidence where the energy is going. This is where automation earns its place. Controls that respond to occupancy, daylight and solar gain, backed by metering that shows where energy is actually used, are usually the quickest and least disruptive improvements a building can make.
They can be installed floor by floor while the building stays occupied. Building controls are also recognised in the way non-domestic EPCs are calculated, so the work shows up where owners and tenants are looking.
Starting small without boxing yourself in
The risk with a phased approach is that the first phase dictates every phase that follows. Choose a closed system for the first floor and you may be tied to one supplier's hardware, software and pricing for the life of the building.
That is why open automation matters so much in retrofit. WAGO controllers are programmed in CODESYS, an open IEC 61131-3 environment, and our modular I/O works across fieldbus standards. A first phase can cover a single plant room or a single floor, then grow as budgets allow, connecting to the systems already in the building and to whatever comes next.
Albion Riverside, beside the Thames in Battersea, shows what that looks like in practice. The penthouse is wrapped in glass and, as Harry Lees of integrator Accurro put it, “there is so much glass, it is like a greenhouse”. Accurro Ltd used a WAGO 750 series controller to track the position of the sun and measure radiation in real time, adjusting heating, cooling and humidity room by room.
The plant room was small, and a conventional BMS panel would have been around four times the size. Because the system is open at field level, Accurro could tailor it in CODESYS to suit the building. In Harry’s words, “once the resident has set the system to the temperature they are happy with, it controls itself.”
Bringing our values to life
We applied the same thinking to our own UK headquarters in Houlton, Rugby. The building runs on air source heat pumps and solar power, harvests rainwater for its washrooms and holds a BREEAM Excellent rating, which places it among the top 10 per cent of UK buildings for sustainability.
It is also home to the UK engineering and technical support team that integrators like Accurro rely on. As Harry put it, “they pretty much always come back to me on the same day with a solution.”
Where to start
The 2031 deadline will arrive sooner than it appears, and the buildings that make the change comfortably will be the ones that start with what they already have. My advice to any owner weighing up retrofit or rebuild is to begin with an honest picture of how the building performs today.
Measure first, control what you can and keep the system open, so that every later decision stays yours. If you are working through the Part L changes on a live project, our Part L CPD session can be delivered to your team.
Explore how WAGO supports building automation and energy management at bit.ly/gb-automation
Join us on 28 October
Connected buildings and plant bring new exposure, and security has to be designed in from the start. On Wednesday 28 October at 11am, I will be joined by Christopher Smith , our Head of Application Sales Engineering for EMEA, for a webinar with E+T Magazine.
We will set out a practical compliance roadmap for cyber security across manufacturing, infrastructure and industrial automation, in a session moderated by E+T Magazine editor Tanya Weaver. Register here.