Yes, and a bathroom is one of the better places for one. What changes is the frame material, because a humid room is hard on timber; privacy, where a roof is overlooked from above; and the fact that a roof window helps with moisture without replacing the mechanical extract a bathroom is required to have.
The frame material
The specification decision that is specific to this room.
A polyurethane or plastic clad frame handles constant humidity better than a painted or lacquered timber one, and most ranges offer a version made for wet rooms.
It is the same window with a different frame finish, and it is worth specifying deliberately.
Why timber suffers
Because the finish is what protects it and steam works on the finish.
A lacquered timber frame in a bathroom needs its finish maintained, and where it is not the timber takes up moisture and the finish lifts.
It is manageable and it is more maintenance than most households will do.
Humidity, privacy and the extract
Three questions every bathroom rooflight raises, and they are the same whichever product goes in.
Why water forms on the coldest surface, why obscured glass beats a blind where a roof is overlooked, and why a mechanical extract is still required, are all set out on can you fit a rooflight over a bathroom.
What follows is what a window in a pitched slope adds to them.
The sloping reveal
Where a pitched installation is harder than a flat one in this room.
A roof window sits in a sloping build up, so the reveal is deep at the head and shallow at the sill, and the head is both the coldest point and the most awkward to insulate fully.
In a bathroom, where moisture rises to exactly that point, a reveal insulated short at the head produces a wet line after every shower.
Why the head is the hard part
Because of how the opening is formed.
Insulation has to be carried up and over the head trimmer and returned to the frame, working overhead in a confined space, and it is the corner most often left with a gap.
It is worth asking an installer specifically how the head of the reveal will be insulated.
A sash that reverses
A genuine advantage of a centre pivot unit in this room.
The sash rotates fully so the outside face can be cleaned from inside, which on an upper floor bathroom removes the need for a ladder outside entirely.
In a room where the glass films with steam and toiletries, that matters more than in most.
Steam and the sash seal
A maintenance point specific to an opening unit here.
Constant humidity works on a gasket, and a seal kept clean compresses evenly and lasts. One left with soap film and dust on it does not.
Wiping the seal occasionally is the whole of the maintenance and almost nobody does it.
Where the window goes
Away from directly over a bath or a shower where the layout allows.
A window over a shower takes the worst of the steam and is the hardest position to reach for cleaning or operating.
Over the middle of the floor is generally better on both counts.
Cleaning it
Easier than most, on a centre pivot unit.
A centre pivot sash reverses fully so the outside can be cleaned from inside the room, which in a bathroom on an upper floor is a real advantage.
A sun tunnel instead
The answer where the bathroom has no roof directly above it.
An internal bathroom with a room above cannot take a window, and a tunnel reaches it through the roof space.
It needs a sealed diffuser and an insulated tube for the same humidity reasons, and the detail is on can a sun tunnel go in a bathroom.
What it does to the room
More than in almost any other space.
A bathroom lit only artificially becomes a room somebody does not switch a light on to enter, and it is the change households mention most afterwards.
Frame material in a wet room
A specification point worth getting right at order.
A painted timber frame in a bathroom is working harder than the same frame in a bedroom, because the finish takes steam several times a day and any break in it lets moisture into the timber.
A polyurethane coated frame, factory finished over a timber core, is made for exactly this room and it is what we specify unless there is a reason not to.
Whether the finish can be repainted
The follow on question, and the answer differs by material.
A lacquered timber frame can be rubbed down and recoated, and in a bathroom it will want doing sooner than elsewhere. A coated frame is wiped rather than painted and is generally left alone.
Knowing which one is going in tells you what the room asks of you later.
The blind track and steam
Minor, but it is the thing people notice first.
Side channels and guide wires collect the film that steam leaves behind, and a blind that runs stiffly in a bathroom is almost always dirty rather than faulty.
It cleans with a damp cloth and takes a minute.
Where the window goes in the room
Decided by the shower rather than by the view.
Steam rises where it is generated, so a window over or near the shower clears the room fastest, while one at the far end waits for the moisture to travel to it.
On a small bathroom the difference is minutes rather than seconds, and it is free to get right at survey.
What we specify on a pitched roof
We specify a frame made for humid rooms, obscured glass where the roof is overlooked, and insulation carried fully to the frame, because this is the room that punishes a poor reveal detail hardest.
The whole picture is on the roof window installation page.
Thinking about this job? We survey across Worthing, West Sussex and the South Downs and give you a fixed price before any work starts, with a 10-year workmanship guarantee.