|1" Diameter Foam|
I'm a big fan of simplicity and keeping things affordable. Here in Seattle in the land of REI and other big outdoor companies we are car rack happy. Daily you'll see tons of rocket boxes, every type of rack accessory on one rack and SUP and kayak racks squeezed on one car. When I started kayaking in 2000 I got the Yakima Hully Rollers which were cool. Then I started to get into whitewater and surf kayaking. Those boats have planning hulls (flat bottomed) which didn't fit well in the half circle kayak cradle shape. So I got the Yakima Kayak Stackers, the vertical metal posts which allow for ww and surf boats to be stacked on their sides. When I added SUPs in 2007ish, these stacked flat on one side tied to the cross bar while my ww, surf kayaks or sea kayaks stacked on their sides attached to the kayak stackers on the other side. Eventually SUP usage outweighed kayak usage and the towers went away.
14 years after adding a rack to my car I'm now just using two cross bars. They are the longest version so I can carry 8 boards for big tours and such (length to side mirror ends). I did go through a period of using fabric pads on the cross bars. Most had brand or shop names printed on the pad but I chose not to advertise other's businesses on my business vehicle. Now I pad them with Insulation foam bought for $1.79 at hardward stores. The tubes slide on easy which I secure with black electral tape or in the below pics, thin bungy cord. They last a good 6 months of heavy use, and are super easy to replace. Pool noodles are also a great option over your cross bars but those are hard to find here in the non summer seasons.
Another advantage of this type of rack is that you can use it for other purposes. SUP and kayak racks limit your roof usage for carrying other items.
Here's a few pics of how I attach the insulation foam. For Yakima cross bars I get the 1" diameter insulation foam. I'm able to use one piece end to end on each cross bar, attaching electrical tape or thin bungy every 1' or so. If you add the tube in pieces, they will roll as you push your board or kayak on the car. This can help slide your craft on easier.