Refurbishing an existing building is now the default rather than the exception. With embodied carbon under scrutiny and demolition harder to justify, more practices are reworking what is already standing, from tired offices to post-war schools. Projects like the low-carbon retrofit of 5 New Street Square show how far the reuse of older stock has come. Yet one feature of that older stock still catches design teams out, and it rarely appears on the mood board. Anything built or refurbished before the year 2000 may contain asbestos, and how a team deals with it often decides when the rest of the work can actually start.

Why does asbestos still catch refurbishment projects out?

Asbestos was used across building elements for decades, turning up in insulation, ceiling tiles, floor coverings, cement products, textured coatings and pipe lagging. White asbestos was only banned in the UK in 1999, so a large share of the buildings now being refurbished predate that line. Before most refurbishment or demolition work begins, a survey is needed to establish what is present and where. The duties around this are set out in the Control of Asbestos Regulations 2012, which place clear responsibilities on those who commission and manage the work.

The practical problem for architects is one of sequencing. Asbestos is easy to treat as a late, specialist box-tick, something the contractor sorts out once the design is signed off. That assumption is where programmes slip. If a survey flags licensed material in the areas a design relies on, nothing invasive can proceed until it has been removed safely, and discovering that at tender stage or on site is far more costly than planning for it. The timing of removal, rather than the headline design decisions, often sets the earliest date the main works can begin.

When should removal enter the programme?

This is why removal belongs in the programme conversation early rather than at the end of it. Bringing in a licensed asbestos removal contractor during the design and planning stages, as specialists such as Mg3 Environmental advise, lets the survey findings feed a proper remediation strategy before the schedule is fixed. Strip-out and removal are then built into the works rather than bolted on when they threaten to hold everything up. Treating remediation as a planned phase, with a clear route for the material and a defined handover back to the trades, keeps the critical path intact.

The regulatory detail reinforces the point. Most higher-risk asbestos work is both licensed and notifiable, which means a licensed contractor must give the enforcing authority at least 14 days notice before the work starts. The HSE guidance on licensable work sets out what falls into that category. For a design team, those 14 days are not a formality. They are a fixed block of time that has to sit in the programme, and they cannot be compressed by goodwill on site. Factor the notice period in at the planning stage and it disappears into the float. Leave it until the contractor is mobilising and it becomes a fortnight of standing time.

How does asbestos shape the design and phasing?

Sequencing shapes the design itself as well. Knowing early which elements are affected can influence what is retained, what is stripped back and how phasing is arranged, particularly in occupied or partially occupied buildings where work has to be staged around people. A classroom block, a hospital wing or a floor of offices cannot simply be closed indefinitely, so removal windows have to be planned alongside decant and reopening dates. The earlier the asbestos picture is clear, the more freedom the design team has to make those calls on its own terms.

None of this makes asbestos the enemy of retrofit. It simply means treating it as a programme item with the same seriousness as structure or services. The teams that handle refurbishment well tend to be the ones that ask the question early, commission the survey in good time and build removal into the schedule as a defined stage rather than a surprise. On a retrofit project, getting the asbestos out on a planned timeline is often what lets everything else run to plan.