For single seam applications.
Narrow windows or roof lights look more old world and in keeping with period buildings. I just think they look cool from the outside and from the inside. The overall size of the window opening is 548mm x 1008mm. The overall height of the window can be increased or decreased to suit an application but best to stick with the standard size for best value. The windows can be used in multiples for a really nice architectural effect or they can be used to get some light into a dark corner where a larger window would look out of place.
For spacing purposes when using multiple windows the following guide should help when setting out the structure as the idea with the View More Windows is all the seam spacing should follow through with the roof as odd seams do not look pretty. If you were having 1 seam in between your Mini window the structural openings would be 500mm apart if you want more seams add up multiple of 529mm for instance three seams would create a structure of 500mm + 529mm + 529mm making a total of 1558mm structural opening to structural opening. Three seams is probably the widest you would have the windows apart for a minimum light requirement.
Our standard windows are double glazed for best value. The top glass is 6mm toughened with a 20mm spacer then a 6.4mm eco therm or similar eco glass making a 32mm double glazed unit with a 1.4w/m2k u value. This can be increased slightly to 1.2w/m2k when using a triple glazed unit of some 40mm thick, the middle pane is 4mm. A greater benefit to this window when using triple glazing is the superior sound insulation. The extra cost is £36.60. Not too much more to achieve the best insulation against rain noise and heat loss. If your strict with your budget don’t worry the double glazed standard window is very solid with 12mm of glass and a 20mm cavity.