Retail roofing is one of the most visible and demanding areas of commercial construction. The roof is the first point of protection for customers, staff and stock, safeguarding everything beneath from the costly consequences of leaks or weather damage.
What’s more, retail roofing projects are often conducted on live or populated sites in constrained shopping centres or shared units, so every hour of operational uptime matters. In short, any retail roofing work needs to happen efficiently, safely and with as little disruption as possible to keep business-as-usual flowing below.
Whether you’re refurbishing a shopping centre or delivering a new development, the same roofing challenges tend to appear. Here are five of the most common retail roofing issues, and practical ways to solve them.
Challenge 1: Minimising disruption above active stores
The brief is usually straightforward: refurbish the roof without stopping trade. The reality, however, is often more complex; any roofing approach which requires open flames for torch-on installation creates obvious safety challenges above occupied spaces, while confined spaces can make it difficult for contractors to move and transport materials without interfering with shoppers or staff.
In such busy environments, flame-free roofing systems offer a real advantage. Cold-applied liquids, mechanically fixed membranes and self-adhesive membranes can be installed in controlled phases, keeping risk low and stores open. Phasing works into manageable sections helps limit impact on retail spaces, whilst off-site detailing (such as preformed cloaks or compatible prefabricated detailing components) and overnight working windows reduce disruption during peak trading hours.
An example of the benefits of a carefully phased installation can be found at the Touchwood Shopping Centre in Solihull, where a 900m² service deck needed refurbishing above 80 operating stores. The deck was split into sections to maintain deliveries and customer access.
IKO Permapark mastic asphalt provided the main surfacing and waterproofing, while the fast-curing characteristics, (subject to system type and site conditions) of IKO metatech cold applied liquid waterproofing handled areas where mastic asphalt couldn’t reach.
A one-way traffic system kept vehicles moving and temporary delivery areas meant goods still reached the stores, with mechanical and electrical services remaining operational throughout. The end result was a roofing system that kept sales flowing during installation, and, if properly maintained, is backed by IKO system guarantee of up to 20 years.
Challenge 2: Managing regeneration and change of use
In many cases, retail roofing projects are conducted on existing structures rather than purpose-built new builds. This could include adapting former residential properties for commercial use, turning shopping centres into mixed-use developments or refurbishing sections of historic buildings to make them ready for business.
Whatever the starting point, material compatibility is critical to securing success. Levelling screeds, for instance, often need to bond with existing substrates before waterproofing can be applied. When such a project targets a BREEAM assessment, relevant product information is essential for supporting the project team’s assessment requirements.
A good example of a project in which material compatibility made all the difference is Broadmarsh Shopping Centre in Nottingham. Beneath the site lies part of the UK’s largest cave network. When incomplete demolition exposed the ancient sandstone caverns to water, it became all the more important to select a levelling solution that could accommodate changes in level and help direct surface water towards the outlets and away from the historic caves.
Our IKO Permascreed solution was selected for the task of bringing the floor level up and directing the flow towards outlets across the 1,000m² deck, while IKO Permapark provided waterproofing and a trafficked surface with a service life of up to 25 years (subject to specification and maintenance). Both Nottingham City Council and Historic England were satisfied that water had stopped leaking into the caves following installation, without disrupting operations.
Challenge 3: Respecting heritage and multi-phase builds
Some retail roofing projects unfold over years rather than months, whilst others involve historic structures where conservation requirements sit alongside modern performance standards.
In situations where conservation officers demand like-for-like replacement materials, and multi-phase developments require systems that deliver consistent performance, roofing solutions need to be up to the challenge.
When Battersea Power Station was transformed into a mixed-use destination, its Grade II*-listed status and the varied uses of the development called for different roofing and waterproofing systems.
IKO Permatec provided waterproofing to retail areas and the main energy centre, where it was combined with IKO Permapark mastic asphalt. IKO ULTRA Gold 20 was used on residential terraces, while IKO Permaphalt mastic asphalt was selected for the bases of the four restored chimneys, reflecting the material used in their original construction.
Mastic asphalt has nearly 200 years of proven use in UK construction past and present, with our mastic asphalt called upon for high-profile heritage sites including Battersea Power Station, as well as the Tower of London, Westminster Cathedral and St Paul’s Cathedral.
For conservation work, it’s frequently specified because it was the original material used in the building’s construction, and its seamless, monolithic finish means it can be formed to suit complex shapes and details – a crucial factor for retail projects that take place in older structures filled with irregular angles.
Challenge 4: Embedding sustainability at every level
Sustainability considerations increasingly influence specification decisions on retail and mixed-use projects, particularly where clients have set requirements for energy performance, embodied carbon or the use of roof space. Architects and procurement teams need reliable product information to assess options against those objectives, including relevant thermal data and Environmental Product Declarations where available.
Depending on the building and its planned use, the roof may also contribute to wider project objectives through planting, rainwater attenuation or solar PV installations. Green, blue and biosolar roof systems bring additional design considerations, including loading, drainage, access and maintenance, which are best addressed during specification.
The recovery and recycling of roofing materials represents another opportunity to address environmental objectives. In 2024, IKO piloted a single ply membrane take-back scheme in partnership with a national supermarket chain, collecting clean PVC installation offcuts and returning them to its Clay Cross manufacturing facility for reprocessing into Damp Proof Course (DPC) membranes.
The pilot diverted 910kg of PVC waste from landfill, with IKO reporting net emissions savings of 2,471kg CO₂e and avoided extraction of 546kg of non-renewable and 364kg of renewable resources. For retail developments and supermarket estates, the initiative demonstrates how coordination between manufacturers, contractors and clients can support material recovery and waste reduction objectives, where suitable collection and recycling arrangements are available.
Challenge 5: Working safely in restricted or complex spaces
In busy high-street retail sites, space comes at a premium. Access, either from the street or loading bays (which are often shared between neighbouring businesses) can be tight, meaning roofing materials have to be carried through constrained spaces, all while the building remains occupied and operational.
Restricted access and limited storage space make early planning particularly important, especially where roofing works are taking place alongside operational retail premises. Delivery arrangements, material lifting, temporary storage and the movement of people around the site all need to be considered before installation begins. These requirements should be addressed through the project team’s planning and management responsibilities under the Construction (Design and Management) Regulations 2015 (CDM 2015).
Early engagement with IKO’s technical team can help identify retail roofing and waterproofing systems suited to the building and its site constraints. Considering material requirements, installation methods and delivery arrangements alongside the wider construction programme can help project teams plan the works while managing the practical challenges of working in occupied or restricted environments.
Planning for real-world retail roofing
These roofing challenges don’t exist in isolation. A heritage mixed-use development might face all five simultaneously, requiring solutions that consider technical performance, operational reality and project-specific factors.
Because works often take place on live sites, retail roofing projects come with a narrow margin for error. Getting it right requires practical experience of how these projects unfold, what can go wrong and how to solve common commercial roof problems before they materialise.
Whether you’re specifying for a new build or phased refurbishment, selecting retail roofing and waterproofing systems to suit occupied spaces, considering environmental requirements or developing a commercial roof maintenance plan, the fundamentals stay the same:
- Agree work phases and access arrangements with the operator
- Review substrates, levels, outlets and junctions before specification
- Resolve heritage-sensitive details and interfaces between roof zones
- Set environmental objectives and request the relevant product/project evidence
- Plan deliveries, lifting and storage around site constraints
- Work with partners who’ve solved these challenges before
Doing so sets the stage for a smooth, successful project that delivers the required roof performance.
