hey thanks for tuning in we're gonna cover how to build a 2x4 skylight curb for a curb mount skylight while we're going to use two by six because that's what the manufacturer recommends you're going to need a few pieces here I'm going to go over the sizes here so the inside dimension here is 22 and 1/2 between this inside here and right there and the outside dimension here is 25 and a half from the outside to the outside and then on the sides we're going to need 49 and a half all right they're from the outside to the outside and then on the inside it's 46 and a half so inside is 22 and a half by 46 and a half and the outside is 25 and a half by 49 and a half so I'll just cut to pieces at 49 and a half and to pieces at 22 and a half already get them set up mock them up like that you want the shorter pieces inside pay attention to this right here you don't want them on the bottom you want to make sure those short pieces are in between or else you're gonna muck it up and this is the last chance to double-check your dimensions here you want to measure from the outside here to the outside over there make sure it's 25 and 1/2 and if you're good you know perfect you can get ready to assemble it you probably want to use screws because from what I've seen on roofs when they get a little bit older the nails they rust out and then your whole skylight curb gets pretty loose so definitely recommend some 3-inch screws just kind of go in through the side here I'll show you over here I kind of come down a little bit lower here and go on an angle see if you get a screw going in here it's just gonna split out the end so I just kind of come up like that and right in there so hopefully this helps just remember those dimensions and you'd be good to go to double check square you got to measure from one corner to the other and I'll just go over what this is I think it's 55 and 3/4 let's put a tape on it yeah how about that you're good so if you want to get it perfect great try doing that but there's a little bit of place validates are made to fit on a curb that's too big by about 3/8 of an inch but that's supposed to include your flashing and any membranes you have so good luck and hope this helps