That black plastic buffer material on the side of boats?

[Andrew]

Are you next to a stream/river/high tide ?

[Andrew]

A single course of bricks using a strong mortar, just inside the garage door (assuming up-and-over) ?.

[Andrew]

Since he seems to have fitted a raised and ?insulated floor of W/P chipboard I assume he isn't going to drive a car over that threshold, so he might just as well do away with the up/over door and brick up the opening.

[Mike Halmarack]

I'm on top of a cliff but the wind here does blow the rain around fiercely.

[Mike Halmarack]

That could work nicely.

[nothanks]

Perhaps better to build a stud wall far enough behind the door to clear the up-and-over door (or closer but with a bulge at the top) so that the "garage" is sealed and insulated but the outside appearance doesn't change and there is a secure space for bikes, small mowers, etcetera.

[Andrew]

then it sounds like you need something attached to the bottom of your garage door (on the outside) that is the equivalent of a rain deflector that would be fitted to the bottom of a conventional timber/upvc/metal front/back/side door.

maybe get a strip of flexible rubber, about 10mm think by 4 inches wide and the width of the door and attach it to the outside bottom of the garage door such that is just makes contact with the ground with the door closed. In fact if it is a normal up/over then you could fit it such that it is about an inch longer than the actual total depth of door plus deflector because as the door closes it will wipe along the ground and with the door closed it will end up curved outwards and act just like a normal weather strip.

[John J]

Boats I've seen had old car tyres hanging over the sides with ropes. Don't suppose that's what you're talking about?

[Chris J Dixon]

The range goes up to 50mm, how deep is your puddle?

Chris

[Mike Halmarack]

That seems well worth a go, though I'm concerned that using this method the rain might sneak in around the edges.

What I should really do is spend a stormy night in the garage, to check out the situation. But neither the spirit nor the flesh are all that keen.

[Mike Halmarack]

No puddle outside. Inside the floor is 10mm awash at times.

[Mike Halmarack]

I could add those for artistic effect!

[The Natural Philosopher]

Those are fenders. same as what the Americans call car wings

[The Natural Philosopher]

hose or pressure washer and a mate is all you need

[Andrew]

Proves nothing (as usual for you). It's the combination of rain and wind that is the problem.

[Mike Halmarack]

Combine the two and apply to join a Paul Mcartney band.