Why this ducting earns its place
A storm collar is the sealed connection where your extraction ducting exits through a wall or roof. It does one essential job: it stops weather getting into your ductwork, protects your filters from moisture damage, and keeps your extraction system running efficiently year-round.
This 400 mm Combisteel collar is sized for large-diameter round ducting—a common specification on busy commercial kitchens and high-volume food preparation facilities. Round ducts of this size move air efficiently and with minimal resistance, making them ideal where you need serious extraction capacity without excessive noise or motor strain.
The 400 mm size handles the airflow requirements of most professional kitchens. Combisteel's industrial build means it won't rust, won't degrade in UK weather, and won't vibrate loose. Bolt or clamp it at the point where your ducting exits the building, seal it properly, and it will perform for years.
