Do I need fancy car carrier for kayaks or can I just tie them to my racks with straps?

You can pick up foam pads at a sporting goods store that are designed as an inexpensive way to carry a kayak. The ones I have seen have slits in them to slip over the rack and are contoured for the kayak, which helps hold everything in place. I believe they cost about $30 for the set. They will protect the kayak from the the rack itself and allow you to tie it down more securely than you would be able to with just the racks. I have seen people use pieces of those foam eggshell mattress pads and old rugs without racks, just putting the kayak on the roof of the car and securing it with tie downs. If you have a rack already it may not cost you much more than $100 for a kayak carrier. I have found them to be well worth the $ as they make it much faster and easier to load the kayak.Do I need fancy car carrier for kayaks or can I just tie them to my racks with straps?
just strap them on should be fine. pass the straps through the grab loops though. the boats can slip a bit but they can't come off the grabs. we were driving to the a rivers put in with a boat haning of the side of the car by its grab loops. the boat was a day old too.... thank god!