reliability of foam block transport

I’ve been cartopping my kayak with a foam block/strap kit for a few years, usually on 20 minute-at-a-time trips, on local roads, so far without any problem. In a few weeks I’m thinking about cartopping with my blocks on about a two hour trip, on highways, to get to my launch destination. I’m a little worried about the kit’s reliability on such a trip. Anybody have experience with this kind of drive? Thanks!

Stop and Check Occasionally
The longer the boat sits on the foam, the more the foam squashes flat. You will likely have to snug up your straps a time or two.

Bow and stern lines
You may want to consider doubling up bow and stern lines (center of the roof to both sides) if you are really concerned.



7 Hours, Highway speed
I made a seven Hour non stop from my home to So. Missouri (Eleven Point River), with the typical Block and strap setup. Average speed was somewhere between 60/65 MPH. I was cartopping a Carolina 14.5, upright.

DOUBLE UP…use TWO cinch straps, (Can’t hurt to add a little redundancy)…use the bumper tiedowns, so IF anything goes wrong, you have secondary control of the boat till you can get stopped.

One additional note: If you want to avoid going stark raving mad from the thrumming of the straps in the wind, make sure you put a twist on both sides of the boat between the top of the boat and the door frame (Twisting the strap once on each side eliminates the vibration).

I wouldn’t trust my yaks or canoes
to foam blocks unless I was just going around the corner!

If you value your boat use a rack system with double looped cam-lock buckle straps.



Foam blocks
I had issues with transporting my yak accross country with foam blocks so I bought Thule racks. But I use the foam blocks on my Thule. If this is your only trip of that distance, then they will work well enough. If you have the money, racks are quite nice as well. They make your car look better too.


I’ve taken many 3-5 hour trips
using the foam blocks. The longest trips were in the 500 mile range. I have a Loon 160T, which is an 80 lb, 16 foot recreational kayak.

Check the straps after the first 20-30 minutes, and then every hour or so. Also, check if you’ve made any sudden stops, as the entire kayak can shift a little. This can loosen the straps, especially if the foam blocks have shifted. Warping of the hull in the hot sun will also affect the tightness of the straps. If in doubt, pull over and check again. It only takes a minute.

Also, be careful not to run a strap too close to the exhaust pipe. Burned through two straps that way! Bring extra straps or some other kind of backup.

An early problem I faced was shifting of the foam blocks. One trick I’ve learned regarding this is to run the block strap through one of the eyes on deck [that guide the bungee cords] or some other fitting. Then, the blocks cannot slip forward or backward. At least this works with my kayak.

On a similar note, I run the large strap [that goes through the vehicle] through the seat rails. That is more secure than just throwing it over the kayak.

To keep the front tie-down straps from vibrating in the wind, I wrap the free end around the standing end several times, then run it past the front door into the car. Then, with the door closed, I can pull on the free end and twist the front strap until the vibrating stops. I tie a short cord to the other from strap and run it through the other door to accomplish the same thing.

no worries
I regularly excede 80 mph with a 18 foot qcc on my corolla, tied down with the foam block ‘welfare rack’. I’ve driven nearly 300 miles at a time also.

Always Always Always use front and rear tie-downs. If you can learn a ‘prusik’ knot (will pull tight, but not loose), it will add a great deal of security to your front and rear tiedown. Tie them to both sides of the car, making a ‘carat’ (^) between the left side of the car, carrying toggle of the boat, and the right side of the car. Doing this fore and aft with a prusik will make the rig very secure.

Invest in a good camstrap - the 1.5" ones from NRS, in the 15’ length are ideal. A wide strap will reduce the “humming” significantly. A duct tape ‘spoiler’ on both sides, where the strap comes off the boat will also mitigate the annoying hum.

In a bad crosswind - this rig may not be as secure as a properly installed yakima/thule setup. It becomes imperative to tighten down the front/rear tiedowns in this situation, and the boat can still shift around up there, but not much. This has only happened to me once in 3+ years of using my welfare rack (where I actually pulled over on the side of the highway to make adjustments). Ive heard plenty of stories about folks who incorrectly installed aftermarket racks (mainly yakima) and had the whole thing (boat included) fly off the car at highway speed because they thought they were bombproof and didn’t use front/back tiedowns.

did I mention the importance of front/back tiedowns?

Hmmm - “once in three years” !!!
That is all it takes!



More foam block advice
Here’s a way to keep the foam blocks from shifting. If the blocks have round holes cut lengthwise through them, get some 1/2" PVC pipe, 2 90 degree joints, and 2 end caps. You can quickly make a “rack” by cutting and assembling the right lengths, and inserting through the foam blocks.

It’s also critical to use good tie-downs, especially in front. Best are hood loops right and left, with an inverted “V” to the bow of the boat. Learn to use taughtline hitch knots so you can cinch things up as needed.

The advantages of using foam blocks include no wind noise, lower center of gravity, much more cushion than a rack, and a “clean” roof when not hauling. I also feel safer leaving my car at a remote put-in when there’s no tell-tale sign that I’m out somewhere in a kayak. I’ve carried boats up and down the East Coast that way, including a 21’ surf ski. I once had a 60-lb plastic boat stay on the roof in a 50 mph frontal collision which totalled the car. Again, the tie-downs are key. (I also have a rack, but just install it when carrying multiple boats.)

Foam blocks do work
The responses regarding good tie-downs, front back and middle straps, and frequent checking are right on. I have been using foam blocks and tie downs for many years without problem. Sure, well-installed custom racks would be better and easier to use, but being on a tight budget, one can get by more than adequately with foam blocks and spend scarce $$ on a good boat and related equipment.

I had a habit of
tightening my fore and aft straps too much without taking into consideration my block placement. One time I actually oil canned the bottom of my composite VCP Aquanaut. I was using the factory rack with foam blocks. The crossbar placement, which was not adjustable, caused too much pressure to be placed on the relatively weak area of the hull right under the cockpit. I had to move the front foam block off the crossbar and position it under the forward bulkhead to correct the problem. Luckily I didn’t crack the gel coat. After learning how to use the blocks correctly, I’ve never had any transport problems.

2000 mile trip with foam rolls
I just got back from a 2000 mile trip with my Old Town Rush rec yak strapped to the top our ‘89 Buick Regal and had no problems.

Instead of foam blocks, which would have forced me to mount the yak cockpit up, I used two rolled up foam pads on each end - these are the foam pads you use under your sleeping bag when tent camping. I used a simple 6’ strap through the middle of each rolled-up pad (6’ X 1/2") to hold them in place on the fore and aft decks. Then strapped the yak, cockpit facing the car’s roof, both bow and stern and over the middle to hold it down. Straps were 1" web belts with ratchets. In western Nebraska we hit side winds of about 30-40 mph and it barely budged.

Only way to go…
…with rental cars!

When I fly cross country for business, I rarely find rental cars come with racks. So either be limited to on-water outfits, many of which cater mostly to beginers and have only barges. Or pack along a pair of foam blocks and straps and rent from kayak shops and launch from anywhere!

I’ve hauled kayaks for more than an hour that way many, many times. I’ve even made my share of mistakes with shifting kayaks. But none ever come off the car. The main lesson learned is the front/back tie-downs. With it, there’s no place for the kayak to go but stay put up there.

Though I must say a rack makes loading and unloading a lot faster to achieve the same level of load security. So if it’s your own car AND kayak, a rack would be a good investment in time, saved for more water time.

No worries!
I guess we all can’t stress the importance of the front and back tie down straps enough!

Tip for keeping the foam blocks in place: If they are the kind with the hole that goes through the middle lengthwise, get a couple of long bungie cords, put them through the blocks and then bungie the cords around your kayak so that the blocks stay in place right where you put them.

I’ve transported a 70 pound, 17’4" Old Town Millennium on a Saturn SL, the smallest Saturn made, at high speeds for hours at a time with no problems. But remember, the front and back tie downs (two in front, two in back, forming an inverted “V” shape) are a must for extra security.

Just a note to those who insist roof racks are better: I agree, generally speaking, and I have them on my minivan. But some cars can’t have racks put on them without drilling through the roof. I used to have a 1990 Pontiac Grand Prix and there was NO roof rack made that could fit the car because there were no rain gutters on that model car. It was impossible to install racks without drilling through the roof. Foam blocks were the ONLY option. Same with the Saturn SL which has a plastic roof, and it dents with the 70 pound kayak on it. It’s those “dent resistant” panels, although why the manufacturer thought I’d need to resist dents on the roof is a mystery to me. Anyway, the roof dents when the kayak is on it and springs right back the second I remove the kayak. The Saturn I have simply can’t be fitted with roof racks because of the plastic roof.

Whatever system you have, those front and back tie downs can’t be stressed enough!