Replace outdoor fixture where existing fixture larger than new one

Question

I have an outdoor light fixture for an "Outdoor Lantern" type light. This fixture is recessed into the siding and has a crossbar-style mounting unit similar to this. I'd like to replace it with an exterior flood light to give the patio more light; I've purchased an exterior flood light kit which includes a new weatherproof surface mount fixture box much like this.

Unfortunately, the hole drilled in the siding for the existing fixture is larger than the new surface-mount weatherproof box can cover. I can't position the new box such that there is no exposed gap to the recessed existing fixture.

What's the best way to install the new light?

Answer 1

A tricky situation. If you can't get a piece of texture matching siding that you can paint to match, then I'd go with Aluminum flashing that you can easily paint & profile to the siding. You'll want to caulk & then screw or pop rivet the siding or flashing chunk to just under the siding's closest above rib to act as a roof for your patch, you're screwing the patch into just the siding & not the building or sheathing. First though, screw in an oval piece of plywood to the building's sheathing to fit in the old hole & fill-up the recess to mount your patch & new fixture to, center drilled-out for wiring. Use aluminum screws or rivets to avoid rusting, caulk your patch to the siding & caulk your fixture to your patch. Also, screw plugs with plumbing tape into the new box's unused holes, even if it's a bottom one.