Loughborough

A 1,500 sq m flat-roof overlay on a working factory

Water ingress was reaching plant and machinery inside a large Loughborough factory, and a roof survey traced it back to previous poor workmanship. We overlaid the whole 1,500 sq m roof with a two-layer bitumen system — detailing around roof lanterns and vertical flashings while the factory kept working — backed by a 20-year workmanship guarantee (the term in place at the time of the works).

The walkway between the two buildings after the overlay, re-covered in clean mineral-finish felt with neat new upstands and flashings dressed against the brickwork.

The flat roof walkway between two factory buildings before the overlay, its surface streaked with old repair compound and scattered debris, with a row of air-conditioning units along one side.

Location: Loughborough
Completed: July 2026
Workmanship guarantee: 20 years (at time of works)
Work: Flat Roofing

How it went

From the first scaffold board to the finished roof.

A worn valley gutter between two slopes of the factory roof before the work: patched, aged felt with standing water and moss, hemmed in by weathered glazed roof lanterns on both sides.

Close view along a worn slope of the factory roof, the felt smeared and patched from previous repair attempts, beside a rain-soaked valley.

The overlay underway: rolls of underlay stacked on the roof beside a fire extinguisher and hand tools, with the first dark layers of the new bitumen system dressed over a slope and its upstand.

Mid-job on the main slopes: new mineral-surfaced sheets laid across the lower roof with the darker bitumen detailing still being worked along the ridges and upstands above.

The finished factory roof: fresh grey mineral-surfaced cap sheet across the slopes, with new black detailing wrapped around the long run of glazed roof lanterns and the saw-tooth factory roofline behind.

The finished ridged slopes of the factory roof in uniform grey mineral cap sheet, seen from above with the wider factory roof and rooftops of Loughborough beyond.

Before01 / 08

Ponding water, tired felt

Water was getting into several areas of this Loughborough factory — enough to reach plant and machinery and shut down the sections underneath. For a business supplying customers across the UK and worldwide, that wasn't something to keep patching.

What we found

The initial roof survey made the cause plain: previous work on the roof hadn't been done properly, and the coverings as a whole were worn out and past their useful life. Rather than chase individual leaks across 1,500 square metres, the roof needed renewing as one system.

What we did

We installed a two-layer bitumen overlay across the existing roof coverings: an Index 3 mm self-adhesive underlay first, finished with an Index Rinova 4.5 mm mineral cap sheet. The roof carries a lot of detail — long runs of glazed roof lanterns, vertical flashings, upstands between buildings — and every one of those junctions was dressed in as part of the system rather than worked around. We also allowed for extra activity around the plant and machinery, so the roof's condition is protected as the factory uses it.

A working factory, not an empty site

The factory stayed in use throughout, and we worked to the client's own strict health and safety guidelines on top of our own. It's one of the larger flat-roof jobs we've taken on, and the result speaks for itself: the client is happy, the roof is watertight under a 20-year workmanship guarantee (the term given at the time of the works), and the relationship has continued into future projects together.