There are a range of features and product options to consider when designing surface water drainage systems.
Here are 5 key considerations you must factor into your plans during the design process.
1. Install Application
Features of drainage systems for commercial or residential applications can vary remarkably. Attributes such as grate lockdowns, type/amount of traffic they will be subjected to, the topography and type of area required to be drained as well as the install process are some of the important considerations.
If the surface has a fall towards a centralised point, a Storm Series or pit/sump would be an excellent choice. If the surface has a fall in one direction, a channel such as Allproof’s polymer concrete (PC) would be appropriate.
Other systems interacting with or adjoining the drain also need due consideration. For instance, if the door/window joinery has a drainage path under the sill, a traditional 3-sided channel installed as a level threshold could block it. Allproof’s perimeter drain would be applicable here.
2. Hydraulic Performance
The surface can dictate the type of strip drain – a narrow slot drain (15mm) would likely be hydraulically bridged if installed at the bottom of a steep slope. A wider channel such as a PC with cast iron grates would provide better catchment.
The grate’s open area plays a key role in hydraulics – some grates may have larger open areas but smaller individual openings. Smaller openings can be prone to blockage but might be required for other characteristics. Maintenance schedules should be considered if this is a concern.
3. Performance Features
Pedestrian and vehicle traffic must be considered, and load class ratings (AS3996) should be referenced to ensure the drains will be suitable for this type of traffic. For pedestrian traffic, other features such as heel-proof grate openings (less than 8mm) and slip resistance (AS4586) should also be considered.
4. Environment
When selecting materials, it is important to consider the life of the product in any specific environment since drainage products are exposed to large amounts of moisture by nature of their application. Materials such as cast iron will react naturally to the environment; it is also aesthetic and does not affect performance. In high traffic applications oxidisation will stabilise quicker, leaving a natural dull dark brown patina. A glass filled nylon or polypropylene grate will retain its black finish.
In marine applications, Allproof recommends 316 grade stainless steel, and for additional protection, electropolishing is an option.
5. Sustainability
Has the selected system been manufactured with sustainability in mind? Allproof’s plastic pits, and domestic and commercial channels are made from 100% recycled material. Additionally, Allproof’s main production facility is powered by solar panels. Allproof firmly believes the process is as important as the product.
