Here is my solution for 4 kayaks outside. In the corner of my yard, I dropped two PT 4x4's in the ground with Quickrete. I used some hanger brackets from Home Despot, each of which is supposed to be able to handle 50 lbs. Over the bottoms of the hanger brackets, I used some pool noodle foam, which does naturally conform to the shape of the boat. On each side, I also have the Riverside 2-kayak hanger straps. A bit of redundancy, but should a good wind come along, the straps will help keep the yaks in place on the brackets. Also, should a bracket fail for some weird reason, my kayaks are not going to fall.

The reason for the extra cross-beam on top is that I built the rack when I only had three kayaks, and I needed to extend it further out (for the strapping) when I got my Perception 16.5' boat. Rather than replace the existing top post, I just lag-bolted an 8' 4x4 on the existing rack.

Each kayak is locked to the rack with a plastic-coated steel cable and a padlock. I just bought a pack of 4 padlocks, so there's only one key. Though this pic doesn't show it, all three of the sit-insides have a Seals cockpit cover to keep out critters. Behind the boats, in a deck box, I keep most of my accessories and gear, excepting paddles. It too is locked off with a steel cable.

I had to go online to find a good-fitting tarp to cover it all up and keep the sun off the boats. I went with a green, heavy-duty, UV-protective version made for outside storage. Tarping everything at once was/is a lot easier than tarping the boats individually. The tarp fits durn near perfectly, and I just use tent stakes in the eyelets to keep it secure.

Here's a pic of the rack all tarped off...

The only thing I would worry about is the thing becoming an oven if the sun shines on that tarp. The heat would not be good for those boats.

Good point, but it wasn't an issue this past summer, even with the green boat which absorbs heat more easily. And I was using a brown tarp (less reflective) at that point.

To add...

It's in a well shaded area, and that green boat has been tarped outside there for three or more years with no ill effects. I've never noticed any sweating or deformations. The boats always feel cool to the touch when I take them out.

Just as an experiment this summer, I might take the temp inside and outside the tarp. If there's a significant difference, I might concoct some way to allow the ends to be more open and let a breeze through.

I doubt seriously the kayaks get anywhere near as hot as they might just sitting out in direct sunlight (on the ground, on a roof rack) on a hot, sunny day.

I made one with 2x4's with arms at a 90* angle. Bought some webbing 4" online. The boats are poly. I can place then in easy and store them deck up or down and on their side. Good part is I can rotate them for cleaning or working on them easily. Living on salt water metal was not a long term I idea for me. They have worked out very well. I can move the two stanchions I made and store then any where. Now I need covers for them.

Does anyone have any experience storing a kayak with a deck-mount compass outside in sub-freezing temperatures? Does it freeze? Does it expand and crack open the case? Thanks.

I cannot see a compass freezing as many are in use in sub freezing temps. Call the manufacturer or email them. I would say if it freezes it was a cheaply made.

I did e-mail Brunton. The tech guy said "sure, it could freeze". But I got the feeling he really didn't know, and was just guessing.

I'm no chemist...Does liquids other than water expand when they freeze?

Outdoor storage. Had my kayak set up under a tarp in the backyard for a few weeks. Just went out to go kayaking today, and found some critter (assuming a chipmunk) spent probably hours and hours and hours storing nuts in the front hatch. Must have been thousands of them. Fortunately, he did his pooping outside the kayak, and didn't chew on anything.

If the compass is any good at all, the liquid inside will not freeze under "normal" conditions. I've kept my kayak, with compass mounted, outside in freezing temperatures for decades of winters without incident. The liquid is often mineral oil, sometimes ethyl alcohol.

Thanks for the feedback. That's what made sense to me.

I have a top-of-the-line Brunton. Based on your experience, I'll leave it mounted. (Due to some issues during the mounting, it's a fairly "permanent" mount).