How to ventilate a Skillion Roof

A Skillion roof is a shallow pitched roof usually pitched between 1 – 10 degrees and is usually quite low offering the minimal permissible height of approx 2.4 metres.

This area was often the leanto extension at the rear of a house that once was the outdoor laundry and now enclosed.

Today dwellings are built with this type of roof are considered to be a cost effective in the build but present problems regarding ventilation.

The indirect venting of residential skillion roof areas, with ceiling heights of less than 2.7m and roof pitch less than 10 degrees, is never entirely successful as the space between the roof and ceiling lining is non existent much the same as a raked or cathedral ceiling.


Areas with this type of roof requiring venting during summer can only be achieved by venting direct to atmosphere.
You will require a roof ventilator on the roof with an closable type of ceiling vent, or register to the ceiling.
This is installed on the underside of the roof ventilator so as to control air movement passing through it.
Much like a window that can be left open in inclement wet weather if necessary.

The ceiling/purge vent selection needs to be a highly efficient design that allows a high flow when required.
This will not be some questionable plastic product that works poorly to begin with and breaks when dust enters the mechanism.
Then you end up with a dust trap that continually reminds your of the flawed choice.

Air ingress (entry)  to this area is critical as the flow necessary could often be high.

Quality of air is also essential with air ingress via door and windows favouring the southern and eastern side of the building.

If you’re going to go the trouble of spending time and money, do it properly, because it will come back and bite you…… the worst possible time.

Condor Kinetic
Venting a Skillion roof
Cathedral roof ventilation
Condor Ventilation Ceiling Purge Vent for raked and cathedral ceilings
Dynamics of skillion roof ventilation

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