Expansion Joint Treatment and Waterproofing Services in Kenya

Expansion Joint Treatment and Waterproofing Services in Kenya

Expansion joints are deliberately created gaps that allow concrete slabs, walls, roofs, bridges and other structural elements to expand, contract and move without cracking. When these joints are poorly designed, damaged or incorrectly sealed, they become major entry points for rainwater and groundwater, resulting in persistent leakage, dampness, mould growth, peeling paint, corrosion of reinforcement and deterioration of concrete.

At Phemat Solutions Limited, we provide professional expansion joint treatment and waterproofing services for residential, commercial, industrial and civil engineering structures throughout Kenya. Our systems are designed to accommodate structural movement while maintaining a flexible, durable and watertight seal.

Why Expansion Joints Develop Leaks

Expansion joint leakage commonly occurs because of:

- Ageing, cracking or detachment of the existing sealant

- Incorrect joint preparation or sealant application

- Use of rigid materials that cannot accommodate movement

- Missing or incorrectly sized backer rods

- Poorly sealed joint edges and terminations

- Damage to waterproofing membranes across the joint

- Excessive structural or thermal movement

- Standing water caused by inadequate drainage or incorrect slopes

- Mechanical damage from traffic, construction activities or maintenance work

Simply covering a leaking joint with mortar, bitumen or ordinary silicone rarely provides a lasting solution. Expansion joints require a properly designed system that remains flexible as the structure moves.

Our Expansion Joint Treatment Process

1. Inspection and Assessment

Our technical team inspects the joint to identify its width, depth, condition, movement requirements and source of water ingress. We also assess the surrounding concrete, waterproofing membrane, drainage and exposure conditions before recommending the appropriate repair system.

2. Removal of Failed Materials

All deteriorated sealants, mortar, debris, dust and loose materials are carefully removed. The sides of the joint are mechanically cleaned to expose a firm and suitable bonding surface.

3. Concrete and Joint-Edge Repairs

Damaged or broken joint edges are repaired using suitable high-strength repair mortars or epoxy repair compounds. Cracks and voids around the joint are treated before the new waterproofing system is installed.

4. Active Leakage Control

Where active water leakage is present, an appropriate water-stopping or injection system may be used to control the water before completing the permanent joint treatment.

5. Backer Rod Installation

A correctly sized closed-cell backer rod is installed to control the sealant depth and create the proper joint profile. The backer rod also prevents three-sided adhesion, allowing the sealant to stretch and compress effectively as the joint moves.

6. Primer and Flexible Sealant Application

A compatible primer is applied where required, followed by a flexible polyurethane or polysulphide sealant. Self-levelling sealants are generally used for horizontal floor joints, while non-sag sealants are suitable for vertical and overhead joints.

7. Flexible Expansion Joint Band Installation

For joints exposed to greater movement or water pressure, a flexible expansion joint tape, such as a TPE-based joint band, may be bonded across the joint using a compatible epoxy adhesive. This creates a reinforced waterproof bridge capable of accommodating movement without tearing.

8. Integration with the Waterproofing System

Where the joint passes through a roof, terrace, basement, water tank, podium or wet area, the expansion joint treatment is properly integrated with the surrounding waterproofing membrane to provide continuous protection.

9. Inspection and Testing

After installation and curing, the completed joint is inspected for adhesion, continuity and correct finishing. Water testing may be undertaken where site conditions allow before the area is handed over.

Expansion Joint Systems and Materials

Depending on the structure and site conditions, our treatment systems may include:

- Polyurethane and polysulphide joint sealants

- Self-levelling sealants for horizontal joints

- Non-sag sealants for vertical and overhead joints

- Closed-cell backer rods in appropriate diameters

- Flexible TPE expansion joint tapes

- Two-component epoxy bonding adhesives

- Hydrophilic water-swelling strips

- Polyurethane or acrylic injection resins

- Cementitious and liquid-applied waterproofing membranes

- High-strength concrete repair mortars

- Protective joint covers for traffic-exposed areas

The final system is selected according to the joint dimensions, expected movement, water pressure, substrate condition and exposure to traffic, chemicals or weather.

Areas Where We Treat Expansion Joints

Our expansion joint waterproofing solutions are suitable for:

- Flat roofs and concrete gutters

- Balconies, terraces and podium decks

- Basements and retaining walls

- Underground structures and parking areas

- Water tanks and treatment plants

- Swimming pools and wet areas

- Commercial and industrial floors

- Shopping malls, apartments and office buildings

- Warehouses and production facilities

- Bridges, parking decks and civil structures

- Precast concrete structures

- Wall-to-wall and wall-to-floor movement joints

Benefits of Professional Expansion Joint Treatment

A professionally installed expansion joint system helps to:

- Prevent recurring water leakage

- Accommodate thermal and structural movement

- Protect concrete and reinforcement against deterioration

- Reduce dampness, mould and damage to internal finishes

- Extend the service life of the structure

- Minimise repeated repair and maintenance costs

- Maintain a clean and properly finished joint

- Protect the surrounding waterproofing system

Why Choose Phemat Solutions Limited?

Phemat Solutions Limited provides technically designed waterproofing and joint-sealing solutions based on the actual condition of each structure. We understand that waterproofing is a complete system—not simply the application of one product.

Our services include professional inspection, surface preparation, joint-edge repairs, compatible material selection, controlled application and final quality inspection. All works are undertaken in accordance with the approved method statement, product manufacturer’s instructions and recognised industry practices.

Where applicable, we provide a written warranty for completed expansion joint treatment, subject to the approved system, site conditions, correct use and agreed maintenance requirements.

Book an Expansion Joint Inspection

If your roof, basement, floor, wall, parking deck or water-retaining structure is leaking through an expansion joint, early treatment can prevent more extensive structural and finishing damage.

Contact Phemat Solutions Limited for professional expansion joint inspection, leak diagnosis, repair and waterproofing services in Nairobi and across Kenya. Our technical team will assess the affected area and recommend a durable treatment system suitable for the joint movement, structure and exposure conditions.

Phemat Solutions Limited

Professional Waterproofing, Expansion Joint Treatment, Concrete Repair and Flooring Solutions in Kenya.