Home Forums General Discussion vented skylights for bathrooms

Viewing 7 posts - 1 through 7 (of 7 total)
  • Author
  • #5183
    Jo Wills

    I’m keen to hear views on double glazed vented skylights in the bathroom of a rental home. The situation is that the bathroom will be small in size and south facing, the options are:

    a) opening window (light/controlled ventilation) and an extraction fan OR
    b) vented skylight (light/uncontrolled ventilation)

    Option a) requires the tenant to use both the window and the extraction fan effectively, we know this is not always the case, but both constitute controlled ventilation (if managed correctly)

    Option b) doesn’t require the tenant to do anything, however the ventilation isn’t controlled – unless a open/close mechanism is included, if not, its 24/7 ventilation, good for ventilation in the bathroom, but potentially not so good for the rest of the house on a cold/wet day?

    Are there other pros/cons I haven’t considered? The bathroom will be next to the bedrooms, all bedroom windows will be north facing and there will be an opening window for cross flow ventilation on the south side next to bathroom.

    My concerns are tenant behaviours and uncontrolled ventilation, as well as – is a double glazed vented skylight enough for a small south facing bathroom to stay damp/mould free?

    Very keen to hear thoughts.



    * Why bother with double glazing if you have uncontrolled ventilation?
    * For an extractor fan that doesn’t rely so much on tenant behaviour, have the fan connected to the light circuit with a delayed switch off, and an air gap under the bathroom door so the extractor can pull air from the rest of the house.
    * Are there other existing damp problems in the house?
    * What climate zone is the house in? Is there heating in the bathroom?


    Jo Wills

    Thanks Alex, yes the extractor fan could be connected to the light circuit with a delayed switch-off. From personal experience, I grew to quickly despise this set up (in my own home), having the fan come on every time I switched on the light, whether it was to clean my teeth or shower, so I am conscious of pushing that annoyance on to someone else. However, this is still an option as performance is the priority, but well being and ease of living is also important.

    This is a new build, so I’m working through the implications of each option…climate zone 2. Haven’t talked about heating yet, but yes that is also an option, however again, given that this will be a rental and expenses will tight (we know this for a fact), I doubt if the tenants would use it because of the (perceived) cost. Although this could be managed or at least address with tenant training.


    What was the annoyance of the fan switching on automatically? Presumably just the noise of it? Were you also thinking about electricity use of the “unnecessary” fan?

    Is it an option to consider a quieter/silent fan, that would not be noticed? Presumably big and low speed.

    I ask about the climate zone and heating really because if it were me I would be doing an estimate of the heat loss from the house by putting a skylight in the thermal envelope, and weighing that against the cost/inconvenience/annoyance of an automatic fan.

    Jo Wills

    Good idea Alex around estimating the heat loss, thanks. The annoyance of the fan was the noise, it was old and loud (and rubbish) and the unnecessary use of it when I only required a light, I would often use the hallway light for the bathroom, so I didn’t have to turn it on. The new fan we have (with our renovated bathroom) is far superior on every level. This is the reality of any new fan we would consider as well.

    Fred Braxton

    How about an automatic humidity-controlled fan? They can be quite quiet and will work regardless of occupant behaviour. Not sure if capital cost but probably comparable to an opening roof window.

    Jo Wills

    Thanks Fred, I will investigate that option further!

Viewing 7 posts - 1 through 7 (of 7 total)
  • You must be logged in to reply to this topic.