Tools needed: knife, hammer, caulk gun

Materials needed: windows, door, flashing, Tyvek tape, silicone caulk

First, cut the Tyvek tape covering up window openings in criss-cross fashion. Roll the bottom and side leafs inside and tape them up there. Tape the top leaf up top to get it out of the way:

Cut Tyvek criss-cross

Check the slope of your window sill: it should be either level or sloped down outwards to let any water that gets through run out. If your sill is sloped inwards, use shims to position your window with a slight angle outwards. Now take flashing tape and start applying it around the window.

First bottom and then the sill. and the sill, and then extend it over the corners. What I did here is old technique, no longer preferred. The new method recommended by GAF is to set plastic corners, and then run tape over without all this stretching (it doesn’t hold all that well). But there were no plastic corners available at Home Depot, so this will do.

Use staple gun to hold stretched out corners in place

Now, insert the window, make sure it’s level, and nail the vinyl frame to the studs. Use roofing nails – they are perfect for that, and be precise with your hammer – you don’t want to smash the window glass or nick the frame. Next run the flashing over the sides, and finally over the top, covering the window frame tabs as you go along. You are flashing from the bottom up to never let any moisture run under, always over.

Once you do this, all that’s left is to slide the top leaf back into position covering up the top flashing.

With the top Tyvek leaf covering the top flashing and secured with Tyvek tape, your window is now securely sealed from moisture. Congrats, move onto the next one. When you are done, let’s install the door.

Same idea goes for the door: cut the opening in I shape, roll the bottom and sides inside and tape them up, get the top leaf out of the way. Flash the bottom, then the door sill, then sides – and install the door. This is where I ran into trouble: my rough door opening was 2” wider and 2.5” higher than the door itself – which is what you are supposed to do according to all instructions I read. The pre-hung door with the rough opening width perfectly, down to 1/8” of an inch. A little too tight even – I had to chisel a bit out to get it in fully. But the height – I was left with a 1” gap at the top.

I still don’t understand where the mismatch occurred. The measurements are correct: rough opening is 82.5” high for the 80” door. But the frame is just 1.5” thick, so I get a 1” gap left. No explanation anywhere, I’m still baffled why. Anyway, I ripped 1” pieces from 2×4 and OSB, sandwiched them together and glued into the gap. Done. I don’t want to think about this anymore.

Fitting the door in.

Once the door is in, secure the door frame to the shed frame and install the locks and handles. I’ve done this so many times with slab doors, it was a piece of cake. After a surprise discovery with the 1” gap, I wasn’t even shocked to see that a factory pre-hung door was misaligned on the handle cutouts and the frame mortises. Cheap production, I guess. I took out the chisel and fixed the issue in just a couple of minutes.

Chiseling out factory misalignments

Congrats, now your shed has windows, a secure door, and you can move in. Next step – install siding.

Front view

Side view