There's no need to solely rely on vertical windows to increase the daylight entering your home. Walls are not the only place for daylight opportunities; don't forget about the roof. Installing a skylight provides several benefits.
Lessen reliance on artificial light
Skylights help you to keep artificial light to a minimum. A conventional skylight, being on a roof, potentially allows up to three times the illumination of a vertical window of the same dimensions, and toplight is possibly distributed more evenly around the room as well. If your windows face a street or a neighbour's yard, you might be tempted to close the blinds or curtains for privacy reasons which, in turn, can increase the use of artificial lighting, pumping up your energy bills. Or else, the windows in your home may be relatively small, so you need extra daylight to avoid switching on lights.
Placement Is Less Constrained By The Environment
Skylights are less constrained than windows by what's outside. The positioning of vertical windows depends on the room structure and what's on the other side, whether it's neighbours or a public street. Particularly if you live in a dense neighbourhood and are concerned with privacy, window placement can be awkward. Overhead space, however, is not generally so congested. Often the only things viewable through a skylight are overhanging tree branches (which you can trim), birds and planes flying overhead and nighttime stars. Though, before positioning a skylight, you do need to take into account the trajectory of the sun throughout the day and also typical weather conditions.
Can Be Customized To Get The Best Performance
This leads to another benefit; skylights can be customised to get the best from your local climate. If you live in an area which typically experiences cloudy days, you can install a large skylight with a diffused glazing system to maximise limited sunlight. Low-E glass can block UV rays to reduce solar heat, and double glazing can provide insulation.
Alternatively, if you reside in a hot, sunny environment, you could fit a sun tunnel, a tubular daylighting device (TDD), which permits less light and heat through than a standard skylight. The circular dome captures direct sunlight beams, directing them through a highly reflective tunnel. Because of the small cross-section on sunlight tunnels, they minimise bright light and heat-gain and decrease the loss of heat from inside as well.
Skylights can also be constructed to provide the most comfortable lighting no matter where you live. Modern glazing techniques can produce moulded versions that favour angled (morning or late afternoon) light over glary midday sunshine. Skylights are typically constructed from acrylic or else glass which can be transparent or frosted to diffuse and soften the light. Diffuser panels on ceilings can also gently scatter the brightness entering through to your home for a more comfortable effect.