I am not going to sugar coat this because this is the part that took the longest of the whole shed building project. But we had some obstacles and mistakes that made it that way. So I am going to share with you an easier way to build a lean-to roof for a shed.
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BUILDING A LEAN-TO ROOF FOR A SHED
The framing of the roof will be made using the standard 2×4 but there is something important you need to do to each board that sits on the shed framing. Let me explain.
If you look at this sketch, do you notice how the 2×4 overlaps the wall framing? You need to cut a notch in each 2×4 with this overlap. This way the board will sit nicely on the wall.
To make this notch, I created a template with a scrap 2×4. Sorry, your template will be different but the key is making a slight notch, like picture below.
SIDE NOTE: We only notched out one side but wish later that we would have done both.
Once I had the template created, I traced it onto the 2×4 I would be using. Then using the circular saw, I cut out the notch.
SIDE NOTE: After completing this step, we purchased a Jig saw and this saw would have been easier to make this cut.
When all the 2×4’s are cut (that need to be), build the roof framing according to your blueprint.
TIP: It will be easier to build this in place (on top of the shed) but if you can’t, build it on the ground then put into place before adding the sheathing.
After the framing of the roof is built (and in place) square it up then add the sheathing. You need sheathing for a roof!
SIDE NOTE: You will want to add some bracing between the roof and wall (where the triangle is!). To do this cut scrap 2×4 to fit into place then attach using screws or nails (we used our Kreg Jig to create pockets and used 2.5″ screws).
ADDING THE ROOF
In this part of the tutorial, I will be explaining how to install a metal roof for a shed.
The first thing that needs to be added is a drip edge. This helps the water run away from the building. This will only be placed on the shorter and taller sides of the shed (something else will be placed on the other sides). But this edge will extend a couple of inches onto the other sides.
SIDE NOTE: You could get away without adding this but I recommend it.
To install the drip edge, use tin snips to cut a triangle from the side that sits on the plywood where the metal will wrap around the corner.
TIP: The point of the triangle is where the metal will wrap around.
Also snip the other side (directly across) to prevent it from flattening. Using the 2″ nails, nail the drip edge to the plywood. Making sure the edge is against the 2×4 frame. Here is an example of what I am talking about.
Using a hammer, hammer down the drip edge so it’s flush with the framing ONLY on the wall sides (not the shortest and tallest sides).
Next, is placing the ice and water shield. This is also to help keep water out. This stuff comes in a roll and it sticks in place. Use a razor blade to cut it and have it the size of the roof.
After is adding the metal panels, you will want the metal to extend 1″-2″ past the framing (will run from tall side to short). If it is needed, cut the metal roof panel to the length you need with tin snips (hopefully you don’t have too!).
TIP: Plan ahead and build the roof to the size of the metal panel!
Place the starting panel onto one edge of the roof. SIDE NOTE: The side of the panel that has a slightly flat side is to place on the roof. The other side is for over lapping the panel. Place the rib inside closure inside the groove (both over hangs will have this). TIP: you can use rubber seal to help it stay in place plus some are sticky already.
Using the 1 1/2″ Galvalume screws attach the metal panel to the roof. These screws will be attached on the flat part of the panel. Only tighten until the foam pad slightly squishes (you will understand when you are attaching). Here is an example of the screw placement.
To add the next panel, add the rubber sealant to the top of the overlapping groove (bump). Then place the next panel, making sure the edges are level. Attach the same way as the last panel but use the 3/8″ screws to attach the two panels together on the bump.
Finish this process until all the panels are installed. After its time to add the gable trim to the other wall sizes. Make size the gable trim is the size you need and if not cut to fit (it will go edge to edge). Place the rubber sealant on the closest bump of the metal panel.
TIP: We added the gable trim after we finished painting the whole shed, this way we would not get paint on the trim.
Then place the gable trim and attach using the 1.5″ screws. Also, attach on the side (along the framing front).
And that is how we built a lean-to roof for a shed plus installed a metal roof. Next, we will share how we finished everything up (trim & siding!).
Did you miss another step of this build?