Adding a shed roof to the backyard

[DoubleStud]

I get this inquiry all of the time and usually the roof goes over a big sliding door and or a window. I usually tell them I will need to know the existing headers of the sliding door and window. More than likely you will need a stronger header (or need to be beefed up). Is there another way to avoid this? Perhaps using a beefier ledger to support the rafters, and the ledger will act as a header over the existing opening? What do people typically do? I see this renovation all of the time? Maybe they just add the roof without even worrying about the header? Homeowners usually expect exterior work and do not expect needing a new header and do interior finish work.

 

[XR250]

I have done it with a beefy ledger before. Can be tough to get the load out at the ends though. Also, need to make it stiff AF or else it ain't doing much.

 

[jerseyshore]

I'd say upwards of 50% are unpermitted. The next 30% no one cares about the headers and they omit it from the plans entirely. The next 15% don't actually check it they just write "exist header to remain" on the plans. The remaining 5% are people like us who actually check things. But the reality is who is opening their sliding door when the roof is loaded with snow so the existing header is probably down the list of potential problem areas for something like this.