Many downtown Toronto homes feature large scale acrylic dome skylights on their flat roofs.  In some cases, these skylights can produce an enormous amount of condensation when the warm air that rises from within a home reaches the cold surface of a large skylight.  The condensation problems are more likely to occur the larger the skylight.  The problems are also more likely with acrylic then glass skylights because of the greater heat loss through the acrylic material.  However, glass skylights installed on a flat roof must be installed on an appropriate slope to prevent heavy amounts of snow from mounting on the skylights.  Therefore, acrylic skylights which are more likely to produce condensation problems but can be fabricated in a dome shape that fullfills this sloping function are a cheaper and more practical option for large scale flat roof skylight installations.  Therefore a trade off exists.

After experiencing condensation problems for some time and attempting several unsuccesful solutions, our clients decided to install two 4 x 4' Velux glass skylights in place of the existing 4 x 8' acrylic dome skylight.  In addition to eliminating the condensation problems our clients also wanted to find a solution for reducing the blazing heat that would result in their upper level rooms, especially during the summer months.  To attend to this second issue our clients decided to install a (VCE) Velux electric venting curb mount skylight with Comfortplus glass and blackout blinds. 

In order to install the Velux skylights according to the manufacturers sloping specifications, we had to fabricate a custom curb mount frame that met these specifications and also met other requirements.  The frame was built such that it allows the two 4 x 4' skylights to sit next to each other in place of the existing 4 x 8 ' skylight.  To prevent snow from mounting on top of the two skylights and to allow for proper curb mount installation we had fabricated an insulated tunnel in between the skylights.  To eliminate potential condensation problems from the frame itself because of the height of the frame required for manufacturers sloping specifications, we insulated the entire frame appropriately.  We then installed our two ply modified flat roofing system as shown in the above video.

Below is a photo and photo gallery of the finished product.  This particular "A-shape" frame is a custom fabrication by M&R Roofing and another example of the extensive skill set and knowledge of our employees.  If you are experiencing similar skylight condensation problems please contact us.