The only way is to cut a groove in the siding and flash the roof wall intersection.
Roof flashing wood siding.
Roof and deck flashing recommendations for coastal areas always lap flashing and other moisture barriers properly.
Lay a shingle over the step flashing starting at the roof edge.
Or pull the nails out of the closest layer of siding and slip the flashing up under it and hopefully under the moisture barrier.
Here s how to install it correctly.
Stop wood sidings at least 1 inch short of the bottom leg at step flashings and other roof flashings.
Reinstall new wood shingles keeping the bottom of the shingle 1 2 above the roof surface below.
Wood siding clearances wood trim and siding should always be installed with an air gap when installed at a roof ground or concrete contact area.
Click to enlarge any image otherwise water will wick up into the flashing leading to paint failures and decay see figure 1 6 above left.
If the sidewall is stucco or solid wood like ours and you can t open it to get flashing behind it continue the step flashing to the peak of the roof then cover the step flashing with cap flashing photo 2.
Flashing is typically used to make the connection between the two.
Buyers of our house want us to fix the roof flashing.
Siding details at roof wall joint step flashings to avoid rot.
Installing step flashing to prevent roof leaks step flashing spans the joint between roof shingles and an adjacent side wall.
Failing to replace step flashings when a cedar shake roof is replaced with a composition shingle roof.
Use increased lap lengths for added protection.
We had the roof installed 1 5 years ago and i asked the roofer to come back and fix the flashing as there was a 10 year workmanship warranty.
Step flashings on a cedar shake roof are typically installed every 10 inches.
It s only on a roughly 15 stretch on a back addition to the house.
Remove wood shingles with care up one or two courses sufficient to install proper sidewall flashing and counter flashing.
It is always recommended to install step flashing behind stucco dryvit wood panel lap siding vinyl siding cedar shingle siding etc.
Do not rely on sealant as a substitute for proper lapping.
A better repair approach for the leaky dormer sides will as we ve discussed involve the following.
Imo and that is all it is.
Epdm flashing tape with a butyl adhesive backing will help.
It looks like it s pulling away a bit from the siding and would need some caulking.
Vent flashing done right to prevent leaks back up roof vent boots with flashing counterflashing and proper shingling.