Many sunroom manufacturers only offer standard 3', 4', 5' and 6' wide and 5' tall windows as a standard.
The manufacturers will deviate from the standard measurements for a custom charge.
But why pay the extra custom charge, when there are sunroom manufactures that fit their windows to the space as a standard practice with no extra charge? When designing new sunroom space there are often existing site conditions to design around.
Walk ways, room projections, room widths and dog doors all dictate the space available for window placement.
If your only options are standard 3', 4', 5' and 6' wide and 5' tall windows, the windows must be arranged to fit with in the parameters of the space.
To accommodate the window size selection available the voids between the windows or the left over space is filled with solid wall panel known in the sunroom industry as "fill".
This may take away from the open feel of a room and the symmetry of design.
Using standard windows could also cause the top of window lines to not match the top of door lines or vertical lines of windows to not match vertical lines of transom or trapezoid glass.
Often landings, walkways and stairs will create more solid wall space "fill" if left in there location or they will need to be moved Sunroom manufacturers that have no standard window sizes will be able to eliminate all the above challenges.
The result is a clean looking sunroom with continuing lines that will blend to existing site conditions at no extra charge.