We've previously mentioned using tidal grids for maintenance. Cordova has several of these, and they are the nicest we've seen, with excellent clearance below the grid to work on the bottom of the boat.

If you've got a flat bottom, like these fishing boats, gridding is easy. Just make sure to check your tide tables carefully to be certain there is a subsequent higher tide to float you off. (You would not want to do this on a really high tide with lower tides in the future, or you'd be stuck for a while.) If you have exposed nonstructural running gear or rudder(s), be sure they do not rest on the grid timbers.

With a sailboat, the situation is a little different. There is going to be some sort of a keel, and the keel needs to be strong enough to support the boat without additional blocking. You also need to secure the boat well to the pilings so that it cannot tip over sideways.

You can also grid with a fin keel, but need to be sure the center of gravity is over the keel and that the keel is well supported by the grid. If you are not sure, check with your builder or designer to see if the keel will support the boat on its own.

Usually half or more of the tidal cycle is available in which to do maintenance chores. This can vary from cleaning the bottom to a complete paint job, changing zincs, polishing the props, or checking the keel and rudder.

Just be sure to check the tide tables.