Ask a tradesman


22 air vents on our flat roof

Our loft extension has a flat roof with 22 mushroom shaped air vents running down either side of the roof (11 either side). The builders say this is because there are 11 rafters which are sealed from the top and bottom, so each space between them needs to be ventilated with an inward and outward air vent. We have never seen anything like this before, and can't find any examples on google. When asked about it, the builders just say it 'is a valid way of doing it'. we are concerned that it provides 22 places where leaks etc can happen.

Is this a good way of ventilating a roof, or are we looking at problems in years to come?

1 Answer from a MyBuilder Roofer

Best Answer

Hi Kai, It should be ok as long as they have been correctly installed. It might be worth while getting someone out to have a look and double check just to put your mind at ease. 22 may seem excessive but the air vents actually could be preventing problems in the years to come. If you had inadequate ventilation new condensation could build up and the timbers could begin to rot because of dampness. There are other ways to ensure ventilation and I'm not sure why they did it this way but your builder is right it is a valid way of doing it as long as everything else is in check.


Answered 18th Aug 2017

Post your job to find high quality tradesmen and get free quotes

Can’t find an answer? Ask a new question

Question Categories