calculating how many windows needed in extension

[iloveglee]

I am having a new bathroom built downstairs with a window which will need a blind as it faces the road, and velux(es) in the roof, which will also need blinds. I cannot decide whether to have one or two veluxes and wonder if there is a way to calculate the size of windows, related to the size of the room. I would like natural light but being a bathroom it is not as if work is taking place in there which will impact on how long electric lights have to be on. The window is east facing. Veluxes are very expensive and I don't want to have the expense of two if one will provide adequate light along with the window.

[The Builder]

Hello ilove ........... I don't think I've ever built, or renovated a house that didn't have at least one Velux in it ........... usually about twelve!
I've never done the maths, but I would guess that light from above (Velux) is possibly equivalent to maybe four or five conventional (wall-fitted) windows.
Facing a road, I wouldn't even bother with a window (it would have to be "blinded" all the time anyway ......) but that's a personal preference.

Depending on the dimensions of the room .......... one large, or two smaller roof windows set low down the roof slope ie sitting on the point where the wall meets the ceiling.

Also, I would avoid the "flat" ceiling, and "vault" it ....... ie ceiling slopey, attached to the underside of the roof rafters. Dramatic effect, and makes the room appear larger.
East facing? ....... morning sun through the Velux ....... :o)))

Also, as they say, other makes are available (cheaper too) ........


http://www.loftshop.co.uk/products.asp?catID=1

[AlBags]

Unless it's small .. and squarish .. probably two!
Dimensions?
Try to have a vaulted ceiling .. probably too late tho.

[iloveglee]

Thanks for responses. No - not too late for the vaulted ceiling, it has already been planned to have one. The plan was drawn with one velux but cannot decide if this would be enough or whether to have two. The length of the room is just over 3 metres, and 1.5 metres wide. It is rather out of proportion length to width but unfortunately this was all the space we had available. There are cheaper versions of Velux I know but velux are so good and come with such a good range of blinds and methods of operation, being in a vaulted ceiling would have to be remotely operated. We are on a budget and want to do this as economically as possible but don't want to end up with a room that's really dark

[buildersmate]

In a room 3m by 1.5m I do not believe you will need 2 Veluxs.

[The Builder]

Agree with BM there, ilove. Veluxes come in many sizes. One large one would be plenty. Sometimes, for the sake of symmetry, two small ones can look better, if they're located at each end of the room, but I agree it would be overkill here.
I guarantee bags of light (as long as you don't paint the walls black) :o)

Also, think about a top-hung model (they also swing around for cleaning). With a top-hung, the handle is at the bottom ......... very easy to reach with a short rod (supplied extra by Velux)

[iloveglee]

thanks for the answers. Providing that we go for a decent size one, should be sufficient.