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Max9 Air Brick


The MAX9 is max because it is the maximum free area for a cast iron air brick 9×9 inch size. The narrow borders and narrow ribs between the 14x14mm holes supplies a very useful 28,000mm2 free area of air making it our most ventilated cast iron air brick. The MAX9 is a robust air brick protruding 50mm deep with 5mm plate and weighs 3.5KG so is expected to last the lifetime of the building and beyond.

This air brick is ideal for large volumes of air either supplying or exhausting to and from buildings and is available in bare metal, to go rusty or painted black (+£15). Use bare metal to allow to rust for a natural finish commensurate with red brick buildings or for customers to paint to their own paint scheme or purchase painted black for use in non-red brick properties or rendered properties.

Painted vents use two part epoxy black gloss top coat which is hard wearing but is just a decorative finish, like all painted cast iron products it will require repainting from time to time, especially if situated on an exposed wall. Repainting can be frequent if the grille is positioned in the sunlight, or chipped or exposed to salt air . The gloss paint will dull over time, in exposed conditions it is likely to dull to a satin sheen fairly quickly. Regardless of the paint finish the cast iron grille will last for many decades with or without painting.

The MAX9 provides ventilation in the prime ministers country retreat in Chequers, England, Walmer castle in Deal Kent , at Jesus College Cambridge University and also the Court House in Cork, Ireland.

The 28,000mm2 of free air flow from a 225x225mm sized air brick makes this our most efficient vent in this size  A very versatile treble sized air brick very common in earlier Victorian and Georgian period properties, mansions, halls and stately homes as well as period industrial and commercial premises where larger than average ventilation is required, especially suited to basements and areas suffering from damp.

For company orders we can supply air bricks in any RAL colour, professionally primed with 3 part epoxy 2 part gloss or matt top coat at an additional cost of £200+vat- please email item number, quantity and RAL number for a proforma for this.

It isn’t possible to install flymesh at the back of this air brick as the mesh will either become dislodged or will block without the ability to clean it. If flies, wasps and bugs are gaining entrance to the property via the vents and are a nuisance the FLY9 cast iron air brick with removable front and integral mesh may be a more suitable alternative or use in conjunction with a duct and attach the mesh to an internal grille (see below) . Please note mesh cannot legally be used (UK – current GAS Safe and HETAS regulations apply) vents where the vents are required to feed a combustion appliance or the room where there is a combustion appliance.

Duct tape can be used to adjoin this imperial sized air brick to  a metric double sized plastic cavity wall duct. This item known as a Cavity Horizontal Extension (CAVHEXT9) can be used to transfer air through the wall to an internal grille such as the Heritage 9×9 (item HER9) .  The duct has a free area of 19,800mm2. Mesh cannot be fitted in this air brick but is more suited to be installed behind the internal grille (and it can be regularly removed for cleaning) were it serves to prevent bugs entering the rooms and reduces draughts, albeit reducing the free air by 1/3rd.

When using the MAX9 please note the free area of 28,000mm2 is only possible when the MAX9 is used without any accessories. Combining it with an internal grille or duct which has a lower free area will reduce the free area to the duct or internal grille with the lowest free area.