romoving ceiling and creating a mezzanine sleeping platform.

I have a 1930’s terraced house and built an extension to the rear. The two rooms that were originally at the back of the house are now in the middle with no natural light or ventilation.

I have converted one into a bathroom and corridor, with an extractor fan venting through the ceiling, the lack of light is not an issue. However, the other room which is my son’s bedroom has no natural light.

I was originally going to fit a solar tube in this room but she who must be obeyed has had a brain wave.

Can I remove a portion of the ceiling, cutting a whole rather like a loft hatch in two or three joists and fitting a dormer windowto the roof, then continue the bedroom walls into the loft space and creating a sleeping platform approx 8' by 5' accessed by a ladder for my son.

Thanks in advance for any advice or guidance regarding the above project.

ps i'll never let her watch grand desighns again.

I've often thought about doing this. What you have to bear in mind (if this is a standard terrace) is that the ceiling joists that run front to back are also in tension, saving the roof's 2 sides from collapsing outwards - think about a triangle.

So you could only cut through a couple of joists safely, unless you had structural work done in the loft to hold the roof in place, which would involve party wall agreements etc.

A light tunnel might be more appropriate (and cheap), fit an electronic velux window up top and form a plasterboard tunnel down to ceiling level and make good the ceiling. Fit the control for the window in the room. You'd need to cut a couple of joists, or retain them as a feature across the opening.

Insulating this 'box' would be a 'mare too.

The room is 8’ by 10’ and currently has a door at each end to “aid ventilation and fire escape” insisted on by building regs.

I hoped the dormer window above the sleeping platform would enable me to do away with one of the doors.