Rectangular Access Pipe

Our hopper heads are available with a wide range of pipe connections to suit round, square, and rectangular downpipes. The Calnethorpe No.11 accepts round 65mm, 75mm, and 100mm; square 75×75mm, 100×100mm, and 125×125mm; and rectangular 100×75mm, 125×100mm, and 150×100mm. Connection options vary by model — please contact us to confirm availability for your chosen hopper.

BTU stand’s for British Thermal Units. This was the old (Imperial) measurement for heat in connection with plumbing. Although BTU’s is a term still commonly used within the heating and plumbing, the industry is now going over to KW’s Kilowatts.

Yes. All our mild steel brackets are supplied in either silver or black zinc plate. This coating protects the metal however, both will need painting prior to installation.

We have chosen to use zinc plating for two reasons; firstly that it is a more environmentally friendly than galvanising and secondly that it does not block up the threaded part of the rise and fall cups in the way that galvanising does.

The Iron Works Patterned Hit & Miss Vent suits Victorian and Edwardian buildings where decorative cast iron or brass ventilation grilles were part of the original specification — including terrace houses, civic buildings, churches, entrance halls, and estate properties. It is appropriate on listed buildings and conservation area properties as a like-for-like decorative vent replacement, and on new heritage-quality construction where period detailing is required.

The School Board Airbrick (F020801AFC) is available in three standard sizes: 225mm × 75mm, 225mm × 150mm, and 225mm × 225mm. These correspond to one-, two-, and three-brick-course heights and allow ventilation requirements to be met across a range of subfloor and wall opening sizes.

The handle is compatible with Lumen Rooflights and most pole-operated rooflight and skylight systems. If you are unsure whether it suits your specific rooflight, call us on 0333 987 4452 and we can advise.

The Calnethorpe is designed for formal classical and Georgian elevations where scale and material authenticity matter — large townhouses, country houses, manor houses, and institutional buildings. It is also widely specified for new-build heritage projects where cast iron rainwater goods are required to conservation standard.

The Iron Works Patterned Hit & Miss Vents are available in two sizes: 225mm × 82mm (single-course, suitable for standard airbrick positions) and 225mm × 150mm (double-course format). Both sizes are available in all three finishes: Antique Black, Polished Lacquered, and Polished Brass.

Size selection depends on the distance between the mounting point and the rooflight frame, and the desired throw (opening distance). Our telescopic openers are available in 150mm, 250mm, and 300mm; the screw-jack stay is available in 300mm with a 250mm throw. For guidance on sizing for your specific rooflight, please call 0333 987 4452 or use the contact form.

The Cast Iron Louvre Airbrick suits Victorian, Edwardian, and inter-war residential and commercial properties where the louvre-pattern vent was the standard specification. It is the correct like-for-like replacement on listed buildings and conservation area properties, and suits new heritage-style construction requiring an authentic period ventilation grille.