For mounting a recessed light, fan, or electrical fixture, you will need to plan the location or have a fixture that mounts on a track so that it is adjustable.
Our channels are 6" wide and your fixture will need to mount in the center of the channel. If you mount on one of the seams where the channels interlock, it will definitely cause a leaking issue.
Please utilize a fixture that will require an opening of 5" or less to allow water to move around the fixture once installed.
Keep in mind when locating your fixture, that our ceiling system does not start or end on a full channel. This will effect where the channels line up in relation to your fixture.
When cutting the opening in the fixture, cut the opening just large enough to clear the fixture. Once the channel is mounted over the fixture, you will seal around the fixture with waterproof sealant.