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Wykamol CM8 Cavity Drain Membrane is a robust, high-performance waterproofing solution designed for use in below-ground structures, including basements, tunnels, and vaults.
Compliant with BS8102:2009 standards for 'Type C' waterproofing, this membrane offers a Grade 3 environment, ensuring a dry, habitable space in areas that were previously damp or waterlogged.
Made from durable high-density polyethylene (HDPE), the CM8 membrane is lightweight, easy to install, and resistant to salts, rot, and contaminants.
Wykamol CM8 is a BBA-certified product (Certificate Number 18/5595) with a life expectancy equivalent to the design life of the building, ensuring long-term protection and reliability.
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Wykamol CM8 Cavity Drain Membrane is an advanced waterproofing solution tailored to the demanding requirements of below-ground environments. With its 8mm studded profile, this membrane creates an effective air gap that allows water to drain away from the structure, preventing dampness and moisture ingress. The membrane is specifically designed for 'Type C' waterproofing, making it ideal for basements and other below-ground applications where maintaining a dry interior is paramount.
Constructed from high-density polyethylene (HDPE), Wykamol CM8 membrane offers superior durability and flexibility. The material’s inherent resistance to chemicals, salts, and contaminants ensures that the membrane remains effective even in the most challenging conditions. Its clear, semi-transparent design simplifies the application process, allowing for easy alignment and secure fixing of Wykamol CM Brick Plugs.
The membrane's installation is straightforward, requiring minimal preparation of the wall or floor surfaces. It can be easily cut to size using a sharp blade, allowing for precise fitting around complex shapes and irregularities. Furthermore, the membrane’s quick installation process eliminates the need for a drying-out period, enabling immediate redecoration, thereby reducing project timelines.
Wykamol CM8 membrane is designed to function as part of a comprehensive 'Type C' cavity drain system, in line with BS8102:2009 standards. When used in conjunction with associated Wykamol products such as Wykamol Waterguard Basement Channel, Sump and Pump Systems, and various sealing tapes, the CM8 membrane forms a complete waterproofing solution. This system effectively controls water ingress by directing any water that penetrates the structure towards designated drainage points, ensuring the interior remains dry and habitable.
This membrane also boasts impressive technical specifications. It operates effectively within a wide temperature range, from -50°C to +80°C, and can withstand a compressive strength of 180 kN/m², ensuring structural stability even under significant pressure.
Wykamol CM8 Cavity Drain Membrane is not only a waterproofing solution but a comprehensive defence system that preserves the integrity and longevity of below-ground structures. It is an essential component in the creation of habitable spaces in basements, ensuring that previously unusable, damp areas are transformed into dry, safe living or working environments.
Comprehensive Waterproofing Solution: Wykamol CM8 membrane provides robust protection against water ingress in below-ground structures, ensuring a Grade 3 environment as defined by BS8102:2009. This comprehensive protection extends the lifespan of basements and other substructures by preventing the deterioration that water exposure can cause.
High Durability and Longevity: Made from high-density polyethylene (HDPE), the membrane is resistant to chemicals, salts, and other contaminants, ensuring long-term performance. Its durability matches the design life of the structure, providing a lifetime of waterproofing protection.
Ease of Installation: The membrane is designed for quick and easy installation, with minimal surface preparation required. It can be easily cut to size and shape with a sharp blade, allowing for precise application in a variety of settings, including complex corners and junctions.
Immediate Redecoration Capability: Unlike traditional waterproofing methods that require lengthy drying times, Wykamol CM8 allows for immediate redecoration after installation. This feature is particularly advantageous in time-sensitive projects where rapid completion is necessary.
Thermal and Structural Stability: The membrane performs reliably across a broad temperature range (-50°C to +80°C) and maintains its structural integrity under high compressive loads, making it suitable for a wide range of environments and applications.
Chemical and Salt Resistance: The HDPE construction of the membrane ensures it is highly resistant to the damaging effects of salts, alkalis, and other common subterranean contaminants. This resistance is critical for maintaining the membrane's waterproofing efficacy over time.
BBA Certified: Wykamol CM8 membrane carries BBA certification (Certificate Number 18/5595), confirming its quality, reliability, and suitability for use in construction projects across the UK. This certification provides assurance to contractors and clients alike of the membrane's performance and compliance with industry standards.
Basements: Wykamol CM8 membrane is ideally suited for use in basements, providing essential waterproofing to prevent damp and moisture ingress. By maintaining a dry environment, it allows basements to be transformed into habitable spaces, suitable for living, working, or storage.
Tunnels and Vaults: In the construction or renovation of tunnels and vaults, where exposure to groundwater is a common challenge, the CM8 membrane offers a reliable solution. It prevents water ingress, thus protecting the structural integrity and ensuring the safety and longevity of these underground spaces.
Walls: Wykamol CM8 membrane is equally effective when applied to walls, preventing lateral water penetration. This is particularly important in older buildings where traditional damp-proof courses may have failed, or in new builds where robust waterproofing is required from the outset.
Floors: The membrane can be applied to floors in below-ground structures to prevent rising damp, which can cause significant damage to floor coverings and subfloor materials. Its high compressive strength ensures that it can withstand heavy loads, making it suitable for use in both residential and commercial projects.
Waterproofing Applications Below Ground Level: Any structure located below ground level is at risk of water ingress. Wykamol CM8 membrane provides a critical layer of protection for these applications, whether in new constructions or retrofitting projects, ensuring that spaces remain dry and free from moisture-related damage.
Wykamol CM Brick Plugs: For Fixing the Membrane to the substrate.
Wykamol Membrane Tape: Provides a double-sided waterproof seal when joining Membranes along the flange where they overlap.
Wykamol Rope: Used to form a seal around the neck of the Waterseal Plug if not using Sealing Washers
Wykamol Corner Strip Tape: Used to link Waterproof Membranes at Floor to Wall joints.
Wykamol Anti Lime Sealer: Used for the control of primary and secondary efflorescence in concrete mixes. Should be applied to concrete surfaces prior to the installation of a 'Type C' Cavity Drain Membrane System to prevent the ‘leaching’ of free lime from the concrete.
Waterguard Basement Channel: A PVC Drainage Channel System which should be fitted around the periphery of an internal floor at the vulnerable wall / floor junction. Any water entering the building through walls or curved soffits is controlled behind the membrane and enters the channel through before being diverted to a Mechanical (Sump and Pump System) or Natural drainage point.
Basement Sump & Pump Systems: Complete water control systems principally designed for use in below ground structures to control water ingress.
Wykamol CM8 Cavity Drain Membrane is suitable for a wide range of substrates, particularly those found in below-ground construction, such as concrete, brick, and stone. It is designed to be used in environments where water ingress is a significant concern, including basements, tunnels, and vaults. The membrane can be applied to both walls and floors, provided the substrate is sound, clean, and free from contaminants that could impair adhesion or waterproofing performance.
For new construction projects, it is essential that the concrete slab is laid in strict accordance with BS 8204-1:2003+A1:2009 standards. This ensures a flat and even surface, with deviations of no more than 5mm over a 3000mm straight edge. This precision is crucial to avoid any air gaps that could compromise the effectiveness of the membrane. For existing structures, any unsound plaster, render, or screed should be removed, and the surface should be levelled accordingly. Where necessary, Wykamol’s Universal Mortar or a 3:1 sand:cement mix incorporating Renderproof Waterproofing Additive should be used to achieve the required surface standards.
Proper surface preparation is vital to ensure the optimal performance of Wykamol CM8 membrane. Begin by thoroughly cleaning the substrate to remove any loose debris, dust, or surface contamination. In cases where walls are affected by mould or masonry fungi, it is crucial to address these issues before applying the membrane. Use a stiff brush to remove surface contamination, followed by an application of Microtech Biocide in accordance with the relevant Technical Data Sheet. If dry rot (Serpula Lacrymans) is detected, a detailed assessment should be conducted, and further advice should be sought from ourTechnical Department.
For installations above ground level, it is advisable to alleviate all sources of moisture at the source, where possible. This can be achieved by installing a Damp Proof Course (DPC), such as Ultracure Damp Proof Cream, before applying the CM8 membrane. This preventative measure reduces the potential for damage to masonry and timber, safeguarding the long-term integrity of the structure.
When applying Wykamol CM8 membrane, it is essential to follow a precise and methodical approach to ensure a successful installation. Begin by positioning the membrane with the studs facing the wall. Fixing is accomplished using Wykamol CM Brick Plugs, which should be inserted into pre-drilled holes at regular intervals of no more than 600mm. This spacing may vary depending on the specific site conditions and the size of the batten or board being installed. To enhance adhesion and prevent lime efflorescence and dusting, it is recommended to apply Wykamol Anti-Lime Sealer to concrete walls and slabs before installing the CM8 membrane.
When drilling holes for the plugs, take care to prevent excessive masonry dust from falling into the cavity, as this could obstruct drainage channels. Insert the chosen plug, ensuring it is fitted with a seal for all underground waterproofing applications, and secure it using a rubber mallet or club hammer. Seal the membrane at the flanges—bands of membrane along the edges where no studs are present—using Wykamol Tape. Ensure that these flanges run vertically on walls and overlap the preceding width of membrane. For horizontal joints, position the lower sheet at the front. In areas prone to severe water ingress, additional sealing with Wykamol Overseal Tape may be necessary. For stud-to-stud joints, use Wykamol Rope to achieve a watertight seal.
When dealing with vaulted ceilings, the membrane can be successfully applied by carefully sealing all mitred joints with Wykamol Tape, Wykamol Rope, Wykamol Corner Strip, and Wykamol Fibre Tape as required. This meticulous approach ensures that even complex structures are fully protected against water ingress.
It is important to recognise the conditions and limitations associated with the use of Wykamol CM8 membrane. The membrane is not suitable for application to flat soffits below ground level, as these require a minimum slope of 10% to function effectively. When running the membrane around internal and external corners, take extra care to ensure that it is fixed tightly to the angle, creating well-defined edges that facilitate the application of subsequent finishes.
The membrane should not be exposed to direct sunlight for prolonged periods, as UV exposure can degrade the material over time. Additionally, while the membrane can tolerate a wide range of temperatures, it should be stored and installed under conditions that prevent exposure to extreme temperatures and open flames.
Finishing the installation of Wykamol CM8 membrane requires careful consideration of the intended final surface. For stud frame construction, Wykamol CM Brick Plugs should be applied in a vertical line, aligning with the stud locations and battens. Fix the stud frame to the plugs using No. 10 screws (5mm), taking care not to perforate the membrane. If straight alignment of the plugs is not possible, 'Gyproc' brackets can be used to secure the battens in place.
When finishing floors, the CM8 membrane can be overlaid with closed-cell insulation before laying tongue-and-groove (T&G) flooring. Ensure a 10mm expansion joint is maintained around the perimeter. Alternatively, a conventional sand and cement screed, approximately 65mm thick, can be laid. The specific conditions of the site may dictate variations to this method, and in cases of uncertainty, it is recommended to consult our Technical Department for guidance.
During the application and finishing process, ensure that atmospheric moisture levels do not exceed 70% relative humidity (RH). Impermeable floor finishes should only be applied when the screed moisture content is below 75% RH to avoid compromising the performance of the membrane.
Wykamol CM8 membrane, once installed, provides a long-lasting solution for controlling damp and moisture ingress in below-ground structures. To maintain a dry and habitable environment, particularly in areas lacking natural ventilation, it is crucial to implement adequate condensation control measures. This is especially important in wet areas such as kitchens and bathrooms. The installation of an effective mechanical ventilation system is recommended to prevent the build-up of condensation, which could otherwise lead to secondary moisture problems. For detailed advice on appropriate ventilation systems, contact our Technical Department.
Wykamol CM8 membrane should be stored in an upright position, under cover, and away from sources of high temperatures and open flames. When stored correctly and installed in accordance with the datasheet recommendations, the membrane's shelf life is equivalent to the lifetime of the structure. Proper storage conditions ensure that the membrane retains its performance characteristics and remains effective for the duration of its intended use.
Wykamol CM8 Cavity Drain Membrane is an integral component of a comprehensive waterproofing system, designed to protect below-ground structures from water ingress. It is compatible with a range of associated Wykamol products, including CM Brick Plugs, Wykamol Tape, Wykamol Rope, and Wykamol Waterguard Basement Channels. These products work together to create a fully integrated system that offers reliable and long-lasting protection against moisture.
For projects involving complex structures or where high levels of water ingress are anticipated, it is advisable to consult with our Technical Department to ensure that the correct installation methods and products are used.
Description
The membrane's installation is straightforward, requiring minimal preparation of the wall or floor surfaces. It can be easily cut to size u