0115 933 5010

Leak Sealing

Structural Polyurethane Solutions

We are one of the UK’s leading specialists providing polyurethane leak sealing services.

Our injection waterproofing is perfect to fill any of your structural leaks.

Waterproof membranes are used to fill leaks, cracks and gaps on any surface that you need, providing a leak tight solution.

Why do you need leak sealing

Forces exerted on reinforced concrete or masonry construction buildings through initial curing, stress movement, vibration, settlement and often poor construction can lead to formation of cracks or voidage and are in need of leak sealing.

Inevitably these will lead to water penetration and the selection of the most appropriate injection resin, grout or elastomeric bandage is where our many years of leak sealing experience are crucial.

Historically the defects listed would lead to breaking out and reinstatement or at worst complete removal and reconstruction and concrete repair.

How our leak sealing can help you

With over 25 years of experience as both structural waterproofing and leak sealing contractors, our team are vastly experienced in providing professional strategies to your problems. Our clients include both the commercial and industrial sectors across the whole of the UK.

Our polyurethane resins are a highly effective way of stopping water leaks. The fast reacting cells in the resin quickly seal leaks once they come into contact with water. This method is extremely fast in preventing further water ingress to many areas such as basements, manholes, the foundations of subterranean structures and many more.

As leak sealing consultants we reduce the cost of extensive reconstruction and sometimes the complete removal of concrete. We can solve any sort of leak sealing problems that you may have.

We provide safety as our main aim in regards to sealing leaks for all types of structures and flooring. As an approved CHAS (Contractor Health and Safety) Registered Contractor we are hot on making sure we not only work safely but provide a finished project that is safe to use.

Contact us online now or call us on 0115 933 5010

Recent Leak Sealing Project -

The Houses of Parliament - London


The Houses of Parliament, or Palace of Westminster as it is also known, was originally laid out for Edward the Confessor more than 1,000 years ago. In 1066 it became the home of William the Conqueror and his court and remained the principal residence of English kings for the next 400 years, until Henry VIII. After that time it remained the main administrative centre for the country up until the present time. The palace was added onto piecemeal, but everything except Westminster Hall was burnt in the great fire of 1834. This magnificent hall still stands at the front of the building adjacent to Parliament Square. The present building was designed specifically to house parliament and was laid out in Gothic style by Sir Charles Barry, completed in the 1840’s.

The structural stone work along the Thames embankment required structural waterproofing, the Thames is tidal and the task required the highest degree of planning and the ingenuity of OnSite Specialist Maintenance.


The solution was the MC Building Chemicals GL95 Elastomer Injection structural waterproofing system. The material was injected to the back of the structure utilising our specialist pumps. The materials cure to form an elastomer waterproof membrane.

The works were carried out over both day and night time shift working from floating pontoons.

OnSite Specialist Maintenance Ltd have carried out a number of contracts to various areas of the Houses of Parliament. The largest of these contracts involved repairs and leak sealing of the river walls. This required a high degree of organisation the works were carried out within strict time constraints and budget. We will not hesitate to utilise their services on future contracts.

Mike Dowding Project Manager Parliamentary Works Services Directorate
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