We have a drippy skylight in our master bath
11 March 2006
A. Skylights are something that have taken Americans a long time to not only get used to but to learn where and how to best utilize them. And we’re still not there yet in many instances. The notion of sticking skylights into houses seemed to arrive over here with a vengeance during the 1970s from Europe where they’ve been used for centuries. The sight of two or three elegant skylights positioned on the master bedroom ceiling looks great on a set of blueprints but after the happy owners get into the hous e they soon learn the orientation of the house exposes the skylights to the rising sun that comes up very early especially in summer and floods the bedroom with bright sunshine at the indecent hour of five AM or so on their only day off.
I remember early efforts where we job fabricated impromptu skylights out of replacement window glass or sliding glass door frames. They were doomed to failure and almost always leaked sooner or later. I learned hard lessons in the art of flashing and t he reality that all caulk is not created equal. American manufacturers were quick to get on the skylight bandwagon but it wasn’t long before the poor performance of the earlier attempts caught up with the public mood and a retreat started taking place. One major American manufacturer even went so far as to rename their skylights “roof windows”. My all time record of skylight installation was thirteen on a single waterfront home on the Eastern Shore. With all the lights on, the house looks like a stall ed cruise ship from a distance at night.
Skylight planners most commonly ran afoul of the direction of the roof face in which the skylight was placed and the problem that arose was solar heat gain in the rooms with skylights. Operable shades and Low-E glass help with that. However, I have neve r seen anyone either passively or mechanically (with a fan) vent the upper areas of a skylight shaft installed in a bath or anywhere else for that matter. It makes sense.
I have a friend who remodeled a bath installing a big spa tub with a skylight directly over it. He wasn’t sitting in that nice hot tub very long before he began to get pelted with icy drips dropping from the condensed water from the underside of the new skylight’s glass and disturbing his warm bath. He called me and the quickest and easiest solution that I could offer was to create a barrier at the ceiling level at the bottom of the skylight shaft that would prevent or at least inhibit the travel of th e warm, moist bath air from getting up into the shaft to condense on the skylight. I suggested fabricating a thin cloth stretched on a frame that could be installed with about 4 or 6 screws at the edge of the shaft bottom that would slow or stop the ai r but wouldn’t block all of the light. It worked. If that doesn’t appeal to you and you can get to the skylight shaft from the attic then you might consider placing a cheap bath vent fan near the top of the shaft that connects with the bath’s light or f an circuit so that when the light or fan in the bath below are on the skylight shaft will vent.