Pry off the vinyl siding and j channel from around the perimeter of the window.
How to install vinyl siding window trim.
Draw a line on the wall along the top of each siding course before you pull the nails.
If your horizontal cut was made at a wider portion of the siding s profile it will fit firmly inside the j channel.
To expedite installing vinyl siding on your home or for large projects you may want to call a professional vinyl siding company.
Not all windows require this but if yours does call a professional for this step.
Cut the trim so it is two channel widths longer than the opening s width.
Unscrew and remove the storm window from the outside of the window.
Install the tops first then the sides and then the bottoms of the window surrounds.
Lift the unlocked siding to expose the nailing hem of the siding piece below.
Fashioning metal window trim with a brake is complicated for a do it yourselfer.
Use tin snips to trim off the metal flashing covering the exterior windowsill.
Install j channels at doors and windows and under roof eaves and rakes.
Remember to leave about a inch for expansion.
Lock the notched siding into place and inspect its fit into the j channel.
Then slide the tool horizontally along the lock to release it.
Along the tops install j channel trim with horizontal siding and base trim with vertical siding.
Alternatively vinyl siding can also be trimmed by scoring them with a utility knife at the point at which you wish them to be trimmed and then snapping the piece off along the scoreline.