Harmer SML, from Alumasc Water Management Solutions (AWMS), is a lightweight, dry-jointed cast iron drainage system, capable of delivering exceptional performance, even in the most demanding of applications.

Harmer SML is a comprehensive drainage solution, with an extensive range of fittings and accessories for effective soil, waste, and rainwater management. It has been a trusted choice across Europe for more than 30 years, being well-suited to installation in exposed areas, such as car parks, schools, shopping centres, hospitals, and busy public buildings. It is fully compatible with other Alumasc systems, including Harmer and Wade roof, floor, shower, and channel drains; enabling a seamless, integrated approach to whole-building drainage.

Engineered for Performance and Reliability

Harmer SML Above-Ground Drainage is manufactured from grey iron to DIN 1691 (exceeding BS 1452 Grade 150). It offers exceptional performance across all areas of building drainage, for the following reasons:

• It is non-combustible: Fire-rated A1 to BS EN 13501-1, negating the need for costly fire collars
• It is fully compliant with BS EN 877, carrying Kitemark certification and CE Mark confirmity
• It is tested to BS EN 14366:2004 for excellent acoustic performance, typically without the need for added sound insulation
• SML offers high tensile and compressive strength, with resistance to both positive and negative pressures up to 10 bar
• Stainless steel and ductile cast iron couplings provide secure, long-lasting joints
• Its durable epoxy coatings and anti-corrosion exterior, ensure long service life and minimal maintenance for the duration of the system’s installed lifetime
• Twin-screw couplings create a socketless joint between pipe and fitting, allowing quick, straightforward installation with no special tools or training required

The Benefits of Cast Iron

Cast iron has long been valued as a construction material for its strength, stability, and long-term durability. Its high carbon content (2–4%) allows centrifugal casting, which produces dense, uniform pipes ideal for drainage applications. This process enhances mechanical strength and impact resistance, ensuring reliable performance even in demanding conditions.

Cast iron’s low thermal expansion and exceptional stability give it a natural resistance to deformation, maintaining structural integrity far better than plastic. Its low coefficient of thermal expansion, ensures SML pipework remains dimensionally stable under temperature variation, eliminating the need for expansion joints or special movement provisions. It is also fire-safe, chemically stable, and unaffected by temperature extremes, making it the preferred material where performance and safety are critical.

Cast iron is both long-lived and 100% recyclable, and as such SML Above-Ground Drainage is a 100% recyclable system with a long life cycle of 40 years. All waste can be returned to the furnace to make new cast iron products, reducing the system’s environmental impact, and maximising life cycle value.

Trusted, Modern Drainage

By combining advanced engineering with the reliability of cast iron, Harmer SML Above-Ground Drainage offers a trusted solution fully in tune with today’s modern construction methods. The value and performance that the system provides is further supported by Alumasc’s compatible product portfolio, and a nationwide network of technical experts, ensuring long-term peace of mind for clients and building-users alike.

Harmer Building Drainage sits under the AWMS umbrella together with Alumasc Rainwater Gutters & Downpipes; Skyline Architectural Aluminium; Wade Building Drainage; and Gatic Civil Drainage & Access Covers. All five brands are well known for innovation, quality and longevity.
For further information, call 01536 383810 or visit https://www.alumascwms.co.uk