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Cemplas Waterproofing and Concrete Repairs Limited


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020 8654 3149

  • ISO14001
  • 67 Pall Mall
  • 67 Pall mall
  • 67 Pall Mall
  • Podium Waterproofing
  • Podium Waterproofing
  • Olympia Roof Waterproofing
  • National Sports Centre (Concrete Repairs)
  • Earls Court (Concrete Repairs)
  • Concrete repairs to columns
  • Museum of Bristol (Concrete Repairs)
  • Victoria House Croydon (Concrete Repairs)
  • Car Park Waterproofing
  • Car Park Waterproofing
  • Car Park Waterproofing
  • Car Park Waterproofing
  • Resin Floor Coating
  • Specialist Floor Screeding
  • Specialist Floor Screeding
  • Resin bound pedestrian access road
  • Resin bonded footpath
  • Tigar Hall - Damp Proofing
  • Basement Waterproofing
  • Cavity Drain Installation
  • External Tanking
  • External Tanking
  • Whipps Cross Hospital link bridge repairs

Cemplas Waterproofing and Concrete Repairs Company Profile

Formed in 1969, Cemplas provides a full service consisting of planning, design and application for Structural Waterproofing and Concrete Repair challenges for both new build, and refurbishment projects across the UK. Previous projects cover premises both below and above ground level, such as factories, basement structures and Multi Storey Car Parks. Lying at the heart of the success of Cemplas is a strong team of Contract managers, site operatives and administration staff, many of whom have at least 15 years service with the company. This is reflected by its Investors In People Accreditation and training programmes to ensure that operatives are both experienced on site and qualified to a minimum NVQ standard. Always fair and equitable in its dealings, Cemplas strives for error-free workmanship and is continually looking for ways to improve results, this approach is the cornerstone of the entire company and underlines its commitment and desire to exceed client expectations.


Structural Waterproofing

Cemplas provides waterproofing services for new and existing basements and concrete decking. Every basement is different, and a site survey by a Cemplas (C.S.S.W) (Certified Surveyor in Structural Waterproofing) is carried out to ensure that the best methods are undertaken. Basement/cellar waterproofing is often carried out using either Cementitious renders, and/or cavity/sheet membranes conforming to BS8102:1990 Code of Practice for Protection of structures against water from the Ground.

Cementitious Coatings used are specialist waterproofing multi-coat render, or a multi-coat cementitious slurry that can withstand the external water pressure present in a basement. For sealing construction joints, expansion joints, connection joints, or cracks and fissures on concrete and masonry, a Hypalon Strip bonded with an epoxy resin is used to provide a high joint movement capacity. Injected resins are used when a more economical solution for isolated areas for Water penetration is required.

Cavity drain membranes work on the principal of allowing water to continue to penetrate the structure but control it in the air gap and divert it to a suitable drainage point or pump. Cavity membranes do not allow pressure to build up against the internal construction, and the air gap behind the membrane allows the structure to "breathe" and dry out. The membranes are impermeable to water, and gas and water vapour, thus protecting the basement internal space from dampness.

Podiums and flat roofs Waterproofing

Many contemporary buildings today incorporate landscaped basements and roofs commonly known as plazas or podiums. The basement can vary from habitable space to car parking, however, whatever the usage, a survey by Cemplas will ensure the correct waterproofing system is selected when there are many considerations to take in to account including deck movement, differential movement, drainage, waterproofing continuity at expansion joints, drainage outlets, landscaping, and most important what is below the deck. Cemplas use high density polyethylene profiled sheets incorporating permeable geocomposite drainage/irrigation sheets designed to prevent ground water reaching a structure and enhance the performance of the waterproof membranes. These can be used in conjunction with a primary waterproofing system or on their own to isolate the structure from the surrounding soil and relieve hydrostatic pressure by promoting the flow of ground water away from the face of the structure to land drainage. Other options are the use of a two coat, solvent free liquid applied waterproof coatings based on polyurethane technology, or two-component, synthetic rubber technology which can be either by spray applied, or applied by roller. These type of products are cured by drawing moisture from the air to form a highly flexible but durable barrier to water and water vapour, and will accommodate minor structural movements.

Concrete Repairs

The first stage when undertaking any Concrete Repair is for Cemplas trained operatives to assess the damage, deterioration and provide a diagnosis of the cause.

A proper assessment will include analysis of the current condition of the structure, including both visible and latent deterioration. An understanding and consideration of the client's objectives, with regard to financial constraints and the future requirements of the structure, is as important, at this stage as the extent of the structure's problems as the results can affect the client's considerations regarding the most cost-effective repair solution.

Concrete Repair is not a standard process as the quantity of work required and the nature of that work may vary greatly, Cemplas consider all aspects of the work including progressive investigation and testing, surface cleaning, preparatory work, and the precise nature and sequence of the repair operation together with the repair methods and materials, and any additional aspects such as weather precautions, material thicknesses and consumption, and curing procedures.

The methods Cemplas undertake for repairing concrete may be divided into the following groups:-

1. Hand applied mortars 2. Sprayed concrete 3. Re-casting with concrete 4. Flowable grouts and concrete 5. Electro-chemical processes 6. Corrosion inhibitors 7. Filling and injection of cracks 8. Sacrificial anodes 9. Carbon composite strengthening.

Car Park Waterproofing

Work on Multi Storey Car Parks are generally extensive. Cemplas will visit the location to evaluate damage and deterioration and recommend the appropriate treatment. Cemplas undertake a combination of Top Deck waterproofing, and wearing course systems to the intermediate decks to afford protection whilst also providing an aesthetically pleasing and durable finish. Depending on the particlular project requirements the products used may be based on elastomeric coatings for use on exposed, intermediate and basement car park decks to provide Waterproofing and crack bridging accommodation, or fast cure MMA resin systems for use in fast track programmes and low temperatures conditions. Solvent free polyurethane systems are also used where fast track applications are required. In addition to the External and Internal deck waterproofing and surfacing, works will normally include Remedial Concrete repairs, together with the application of Anti-Carbonation Coatings to both the internal and external concrete, sealing of expansion joints, Line marking for demarcation of parking bays and traffic flow, and decorative slip-resistant coloured surfacing.

Resin Floor coating

Cemplas apply various Resin flooring coatings ranging from plant rooms, warehouse and factory floors to provides a long-lasting, high performance system for the most exacting situations. Choosing the correct system to meet the specific flooring usage is an important part of the selection process. Resin flooring is applied in two or more coats with varying thicknesses depending on the usage of the floor, thickness can range from up to 150 µm up to 6mm. British Standard BS8204-6 forms the basis of the system for the different floor types.

Specialist floor Screeding

Cemplas specialise in laying sand/cement modified polymer screeds which can be laid at a minimum of 6mm Cemplas will prepare the substrate by scabbling or blasting to remove loose particles of cement and sand and expose the aggregate within the sub-floor, the modified screed is applied in the traditional manner on to a prepared, sealed and primed surface to provide a high strength, monolithic bonded screed.

Self Smoothing Pumped floor Screeds

Self smoothing pumpable screeds and toppings thickness can vary from 5mm to 25mm depending upon the grade selected, and are supplied as a free flowing cement based dry powder which requires a known quantity of clean water to produce a self-smoothing mix ready to pump or pour on to a prepared, sealed and primed surface.

Bund Lining

As a member of the Utilities Vendor Database, Cemplas is qualified to provide this treatment designed to contain dangerous chemicals within restricted storage area. Bund lining and containment are most popular with companies that hold large amounts of oil and chemicals in bund tanks.

Damp Proofing and Timber Treatment

Cemplas offers solutions for the protection of timber located below and above ground level, providing an ideal treatment for the refurbishment of older buildings. The company only uses natural formulations to treat the wood, ensuring that older materials are not affected by high acidity solutions. Cemplas may also apply a fungal spray for the treatment of specific areas, therefore avoiding spraying the whole structure, and ensuring the most environmentally responsible approach.

Cemplas experience in Waterproofing was used to design the Industry’s first Structural Waterproofing NVQ which is made up of practical work, and written papers, and since 1969 we have worked closely with many Architect and Engineering practices who have utilised our in-house expertise to provide assistance and solutions with complicated design detailing, budget costings, through to competitive tendering.

Cemplas are ISO9001 accredited, and all our work is backed up with our own 10 year workmanship guarantee, or we can provide an insurance backed guarantee which is underwritten by a third party to provide our customers with additional peace of mind.

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Holbrook House
72 Lower Addiscombe Road

Tel: 020 8654 3149



What We Do