The choice of the most suitable ducting is important in order to optimise the efficiency of a system, to make it as silent as possible, to keep it hygienic, and in order to get it installed easily. The efficiency of a system mainly depends on the smoothness of the inner surface, the dimension, the number of bends and the length of a ducting system.
Following systems are available:
–Semi-rigid ducting, round:
The system is based on one extract and one supply manifold with continuous hoses into the various supply and extract rooms. We offer Polyethylen hoses, which are relatively smooth on the inner surface and therefore almost as efficient as spiral ducting. Besides the high hygienic qualities, it is also easy to be cleaned. The installation is easier than the metal ducting. The ducting we supply has a 90mm exterior and 76mm interior diameter. While we keep to the best practice 2.5m/s flow speed, in most cases one duct per room is sufficient. We source our components from various suppliers, in order to provide the highest quality system. Lindab’s InDomo system is one of our suppliers.
– Rigid metal ducting, round (Spiral ducting): Highly efficient and hygienic ducting. we recommend the safe system with double seals at all connection points. Standard dimensions of 100, 125, 160 and 200mm are used for domestic applications. The disadvantage is the number of different components (T-pieces, reducers, bends) and that the design and installation process is quite intricate. Also cross-talk silencers need to be installed between the bedrooms.
– Rigid plastic ducting, round or rectangular: Needs to be glued together. Such ducting has a much higher resistance as the plastic bends have a very sharp radius. Due to this it often costs more money to operate such system. Rectangular ducts have the advantage of a low profile, but they have even worse air flow properties and can never be cleaned any more. Also cheap materials can give away chemicals and are not as hygienic. Therefore we generally do not supply this ductwork.
– Flexible ducting: It is very inefficient and hardly ever cleanable. It is recommended to avoid fragile materials as foil or plastic ducting and rather use canvas material with wire. Flexible aluminium ducting tends to be rather noisy. Strict guidelines on installation have to be adhered to and all connections have to be secured with jubilee clips as tapes can come off through fatigue of the adhesive or movements. We do not recommend to use this ductwork.