here we are at salt spring island in a small room above a living room an attic type roof and installing Scylla so how to make roof larger in the vaulted ceiling like this or a cathedral ceiling one ways to install skylights and you can have an opening skylight and a fixed skylight so that's what we're doing here let's go deciding where to put skylights in your room that's a good question most homes are framed with 24 inch centers on the rafters what we'll do then is mark them out decide where they're going cut the drywall frame everything in from underneath because it's pouring rain outside right now I definitely recommend having whatever ventilation you can into attic spaces or to any space for that here's stage 2 of installing a skylight and your cathedral ceiling essentially cutting through the drywall you see here drywall was right on the rafter that's a 5/8 fire stop drywall 2 by 10 solid fir rafters that's a 1212 so that's 45 degree angle and the original strapping material here it's a strong roof this is 2 by 4 fir on 7 inch centers that's called a flair skylight what that does is even if you have a 2 foot skylight or a four foot skylight you can maximize the amount of light you get this is an example of a skylight this is a non opening skylight in a cathedral ceiling had this line here when carried out horizontally it could actually gain more light by flaring the open of the skylight more parapet the raw opening through the rafters in preparation for the skylight boxes it's a 2 by 6 curb that will be installed on the roofing itself and then flashing will be then added around the perimeter here's the rough curb installed and the skylight before the drywall is installed I ordered black skylights for this project being a black roof and black step flashing which was integrated with the existing roof once all your rough framing is complete and your skylight is installed remember to add vapor barrier and tape it is important to seal all air gaps after your drywall is installed use preformed corner beads mud and install once your painted you'll have unique space that's much more enjoyable