Nailing Step Flashing

I’m just wondering if there is a proper way to nail step flashing where a roof meets a wall. Where is the proper place to place the nails? On the roof or on the wall (if both can be accessed)? Is there a best practice or is it a preference of the roofer?
On an unfinished roof and wall, I’ve seen some roofers put one nail in the wall and some roofers put one or two nails in the roof.
Just wondering what’s the best approach and why.


This will most likely be a debatable subject.

I’ve worked for people who swore that you should never nail step flashing, some who nailed into the wall part only and others who nailed into the roof part.

I’ve seen older roofs where the step flashing had slid out of place due to not being nailed, some where the steps were sticking up at the corners and looked bad from nailing only the wall part and others where the nails were put into the roof part too close to the wall causing leaks.

My personal preference is to nail into the roof part right at the bottom corner and put some sealant on the nail head.

Bottom outside corner, about 3/4" to 1" up, never into the wall, except for some strange ‘last resort’ situations that crop up every few years or so.

Bend them 80 degrees, NOT 90! Shove into place, and nail the lower corner. The top will spring out a bit. Don’t worry. Place and nail the next shingle. Shove the next SF into place. This will realign the top of the prior one and literally seal them together when you nail the lower corner. That nail will also lock the prior one. Continue to the top.

At ridge, I loose aly the firs one until I come up the other side. Then, I scissor lock the last one on each side together, then nail them. A 1/2 ‘dime sized’ bit of caulk can be added to complete the project.



[attachment=0]Scissorlocked with Top Lock.JPG[/attachment]

If you nail on both roof and wall you will most likely get some buckling as temps change.

I nail it to the roof, top outside corner.

We did it the same way tinner at ridges, its amazing how many don’t know these methods…just give me a gun…i m the fastest…whoopee chit…don’t mean krap if ya don’t know the basic rudiments of roofin…

I nail it to the roof, top outside corner.

This is the only correct response. No sealant needed as the nail head is away from water flow and the placement is conducive to future repair/removal or replacement. There are many ways of doing a thing but only one is most efficient.

I try to never nail into wall/curb. Makes it easier for a reroof down the road. That is if the siders(ive found vinyl guys the worst)dont put their siding right on deck.

I have yet to come across step flashing that isn’t nailed to the wall by siding & accessories.