Description
Insulated Ducting 125mm (5″) provides the intermediate size between the common 100mm and 150mm formats, serving the specific requirement of ventilation systems built around 125mm inline fans. The thermal insulation construction reduces condensation formation on the duct exterior and minimises heat exchange between the duct interior and the surrounding environment, both of which improve system performance and reduce the risk of moisture damage in the ducting run.
The three-layer insulated construction — inner aluminium duct, insulation core, reinforced outer jacket — delivers suppressed condensation on cold duct runs, reduced heat transfer that helps maintain accurate room temperature management, and improved structural stability compared to single-skin flexible duct over long or unsupported runs.
The 5-inch size is frequently overlooked by growers who try to adapt to 100mm or 150mm ducting to avoid stocking an additional size. This always creates a restriction at the adaptor point and reduces fan performance. Using correctly sized 125mm ducting throughout the run maintains full airflow efficiency and avoids unnecessary static pressure increase. Sold per metre; secure with 125mm fast clamps. Available at The Horticulture Company alongside the full insulated and standard ducting range in all common grow room sizes.
Browse the full range: Explore our Ducting and Fittings range, part of the wider Ventilation and Environment Control section at The Horticulture Company. Also in this range: DUCTING Y PIECE, FAST CLAMP (SYSTEMAIR), COMBI DUCTING 315MM / 12″, 90° METAL BEND.







Reviews
There are no reviews yet.