Ducting

For the Trade

What usually decides it is the route, the airflow you need to keep, and how much room you’ve got to work with. Long, straight runs need a different answer from short links with a few offsets, and that is where the choice gets made on site rather than on paper. If the run is exposed or likely to get knocked, you usually want something that holds its shape. In a tighter void, movement and access matter more. Aluminium ducting and plastic ducting each get picked for different reasons, but the job still starts with the layout and the space available.

Ducting Options Compared

For most jobs, the choice comes down to route and space. Flexible ducting earns its keep on awkward offsets and short links where you do not want to fight the run, but it is not the best pick when you need a line that stays neat and stable.

Rigid ducting holds its shape better and gives a cleaner result on straight sections. Flat ducting works when the void is tight and height is the problem. Round ducting is the straightforward option for open runs. Oval ducting sits between round and flat when you need less depth without going fully compressed. Insulated ducting is the one to use where condensation or heat loss would cause trouble. If you are working through the wider Ventilation range, the run layout usually decides the product.

Choosing Materials and Size

Material choice usually comes down to handling and how much abuse the run will take. Plastic ducting gives you lighter pieces, quicker handling and a lower-cost line through the job. It can be less forgiving if the run is exposed or likely to get knocked.

Aluminium ducting suits hotter or more demanding runs and gives you a firmer finish. It is less forgiving to handle and can be awkward on tight bends. If the job is tied to Extractor Fans or Fans, the choice often comes down to speed versus a cleaner, tougher run.

Completing the Setup

Once you’ve picked the ducting, the next call is what finishes the run and what the surrounding job needs to stay tidy. Long exposed sections need proper support and a clean termination. Short connections into a hood or grille usually just need the right fittings and a sensible route.

If the run passes through a cold void, insulated ducting avoids nuisance condensation. It does add bulk, so use it where it earns its keep. Keep access in mind too. The neatest duct pipe is no use if you can’t get the rest of the finish in around it.