That black plastic buffer material on the side of boats?

What about using a cable protector? This sort of thing:

It might be better to use something stronger if you're driving over it a lot. I doubt, though, that even if you use silicone cement on the underside you'll stop water getting through.

Yes, thanks, that's a possibility, though I had in mind something a bit more upstanding and wall-like.

Garages are much too valuable to be containers for cars. :-) And anyway, I don't have one.

Oh no! My hopes are dashed.

A nice neat job. As I happened to have a spare arris rail, and never drive into my garage, that and a tube of No Nails soon solved a similar problem.

Whilst looking at the web page I also had a glance at their garage door insulation kit, and wondered about using something similar. I guess the materials are probably available cheaper elsewhere.

I would have to arrange matters so that I could still pull the internal wire between the lock and latch to open it from the inside.

Chris

No, we used to find that it would even get in under the side, even though it looked firmly bonded to the base and had in effect a a dam on the inside. Water is very difficult to keep out. You really need some kind of drainage grille to do it under doors. Brian

I believe they are called rubbing strakes.

Mike Halmarack wrote on 11/12/2021 :

Difficult to stop it going in with a dam, better to have somewhere low for it to drain to just outside the door. I hsve a cast-iron grid, just to the outside of my roller door, which makes a big difference.

what about using the thick plastic trunking that is used to protect electrical cables when they run across walkways?

Example

A drainage grill is a very impressive option and effective too. I've built these into new concrete in the past but I'm tending toward more lightweight options these days.

Very professional looking but I'd feel happier with more height.

That's the first possible solution that occured to me. I do tend toward the frugal. As it is I seem to be putting more and more stuff into the garage these days, like tools and materials, so I'd better make a bit more reassuring job of it ( I hope).

That sounds exactly right, though the responses to my post have moved me more onto dry-(please)-land solutions now.

I really do like the crest of the wave form with this stuff. It's definitely on ther shortlist.

That's the best solution for sure. Not one I'd tend to be rushing into these days.

I do have easy access to some of this but I think something a bit more belt and braces is needed.

This is a lot more like what I'm needing, though I was quite impressed with the overhanging wave form that Andy Burns link showed.

In the video showing the fitting of this I did wonder about the crest of the material being pushed tight against the inside of the garage door causing a capillary effect?