IN Brief:
- NISTA has downgraded the cladding remediation programme’s delivery confidence from Amber to Red.
- Work has started on 2,399 of the 4,322 buildings identified with unsafe cladding.
- Gateway 2 delays, rising costs, and social-housing pressures are weakening programme certainty.
The National Infrastructure and Service Transformation Authority has given the government’s cladding remediation programme a Red delivery rating after concluding that its cost, schedule, and scope assumptions face substantial pressure.
Delivery confidence was lowered from Amber at the end of the 2025/26 financial year, with the assessment identifying Building Safety Regulator delays, higher-than-expected volumes of affected social housing, continuing construction inflation, and the pace of developer-led work as the main constraints.
By the end of March 2026, 4,322 residential buildings above 11 metres had been identified with unsafe cladding. Remediation had started on 2,399 buildings, including 1,531 where work was complete and 868 where contractors remained on site, while another 1,923 identified buildings had yet to enter physical remediation.
Although the identified total is substantial, it is estimated to account for only between half and three-quarters of the buildings that may eventually require work under government-backed programmes. Surveys, responsible-entity investigations, and reviews of previously unregistered buildings could therefore add further schemes to an already congested pipeline.
A Red assessment indicates that successful delivery cannot be considered achievable without substantial intervention. It follows the government’s Remediation Acceleration Plan, which introduced stronger expectations for building owners and developers while seeking to increase the number of projects moving from investigation into design, regulatory approval, and construction.
Government action is now concentrating on increasing the flow of Gateway 2 decisions, developing delivery plans with social-housing providers, and pressing developers to move affected buildings into funded programmes. Preparations are also continuing for the Building Safety Levy, scheduled to begin in October 2026, which will place an additional charge on qualifying residential developments to support remediation expenditure.
Physical façade replacement forms only one part of the programme. Before site work can begin, each building must pass through intrusive investigation, design development, resident consultation, commercial agreement, funding approval, procurement, building control, mobilisation, installation, inspection, and final certification.
Where those stages become disconnected, contractors can be left holding provisional programme slots while access systems, specialist designers, fire engineers, and façade subcontractors remain committed elsewhere. Tender prices can also lose validity as approval periods extend and assumptions about labour, materials, and temporary works change.
Gateway 2 remains particularly significant for higher-risk buildings because construction cannot begin until the Building Safety Regulator has approved the proposed work. Submissions must coordinate fire strategy, structural interfaces, product selection, compartmentation, access, sequencing, and responsibility for design changes, with incomplete evidence often returning projects to clarification.
Greater regulatory scrutiny is also exposing weaknesses inherited from the original construction. Façade replacement is rarely a direct exchange of one cladding product for another, especially where opening-up works reveal undocumented substitutions, poorly installed cavity barriers, weak compartmentation, or interfaces that differ from the available drawings.
As a result, contractors are increasingly involved before the final construction package is settled, contributing to surveys, buildability reviews, temporary works planning, sequencing, resident protection, and product assessment. That early input can reduce later design movement, although it requires clients to fund meaningful pre-construction work rather than seeking firm prices from incomplete information.
Public-sector clients are also creating larger procurement routes that combine construction capacity with specialist compliance requirements. Portsmouth’s £120m tower remediation framework brings façade replacement, fire-safety work, resident liaison, and higher-risk building capability into a coordinated programme instead of procuring each block separately.
Social landlords face an additional layer of pressure because remediation competes with planned maintenance, energy-efficiency upgrades, housing repairs, and new supply for the same capital budgets. A larger-than-expected number of affected social-housing buildings changes the programme’s funding profile while increasing the need to coordinate work around occupied homes, vulnerable residents, and temporary safety measures.
Long approval periods also magnify construction inflation. Scaffold hire, temporary alarms, insurance, professional fees, specialist labour, and fire-rated products may continue rising while designs remain unresolved, and changes made after tender can reopen commercial negotiations across several connected packages.
The Building Safety Levy will increase the funding available, but it enters a residential market already managing viability pressure, planning obligations, borrowing costs, and slower starts. Its contribution will depend on how quickly receipts can be converted into approved, procurement-ready projects rather than remaining within broader programme allocations.
Improved delivery confidence will require a steadier passage from identification into coordinated design and then through regulatory approval without projects repeatedly losing their place in contractors’ programmes. Work is progressing across more than 2,000 buildings, but the remaining pipeline still depends on funding, technical assurance, regulatory capacity, and the availability of specialist delivery teams.
