Hi. Getting ready to buy my first yak. I’m hoping to get in some after work paddles this summer. The problem I have is that work is about an hour away from home, and all of the local paddling spots are within a few minutes of work.
Can I safely keep my plastic kayak on my roof for a 8-10 hours a day a couple of times a week, or is that too long? We do have a parking structure that I could look at using if that would help, but not sure about clearance with the boat on top of the car (Grand Caravan).
Thanks,
Mike
I don’t understand the question
Will your boss object? Do you live in 110° weather and the boat will melt? What is the concern with keeping it on top of your car? FWIW, I keep my on for months on end.
some risk
Long time exposure to ultraviolet light can break down plastics and high temps can cause pressure points to mishape and then there is always the possibility of theft. Other than that I see no problem.
What kind of boat?
– Last Updated: Jun-23-10 9:37 AM EST –
You can deform a rotomolded plastic boat by strapping it down too tight and/or leaving it on your car in the heat. It doesn't have to be a 110 degree day either. I have a purple WS that gets smoking hot in direct sun (dark colored plasic boats are a stupid idea in my opinion).
I think the best long term solution to the problem (besides not using the boat!) is investing in a pair of J-cradles from Malone, Yakima or Thule. They distribute the load better and support the boat on it's side (the strongest part). Compared to the cost of a new boat, a pair of cradles or even a full rack system is paltry.
UV can damage a plastic boat, but 303 does a reasonable job slowing the process. Think of it as sunscreen for your boat.
Doug
racking a plastic boat
living in Cinci you will get some pretty hot summer days. Up here in MI we’re already consistently in the 80s in midJune, a big contrast to last year at this time.
If your weather is on a hot streak and if you really crank down on the gunwhale straps, your plastic boat hull, left that way for hours will more than likely deform. I saw a few of these myself on Sunday helping some paddlers unload and get launched… our high temp was 86, sun all day.
These dents usually pop back, sometimes they are all gone, sometimes it takes extra TLC back on land w. a hairdryer or weights, sometimes over time it will warp the boat. Depends in part on how often, how hot and the quality of the rotomoulded plastic, as different companies use their own formulas and thicknesses in rotational molding.
my advice would be:
sure, park in the shade if you can - under a tree, side of a building, a parking garage if there’s clearance. Lowers the temp, shields the boat from direct UV exposure that over time will make plastic brittle.
when you park, before you leave for work, loosen the straps just a bit.
remember to re-tighten when you go for that afterwork paddle!
and enjoy your boat, it’s tough, it can take a lot. But a little extra care will keep it at its best.
Suggestion:
A lot of the tarps they sell are silver on one side.
Why not get one that is as long as your yak, and wrap it while it is stored on the car.
Prior to putting the yak on the roof lay the tarp out up there so the silver side will be out. Then put the yak on it, and wrap it.
Lastly strap it down.
I keep several long composite boats on my roof for four monthes when I am in the Florida Keys in the winter in the hot sun, but I wouldn’t do it with my long plastic Eclipse.
Jack L
J-cradles
I’d second the recommendation of buying J-cradles for your boat.
Normally I’m a proponent of getting a boat to the water in the cheapest safe way, but I think your circumstances warrant spending a little more. Supporting the boat on it’s side, and with wide contact points, will do a lot to keep the boat in it’s original shape. If you use deck up cradles, or strap the boat deck down in the wrong spots or too tightly, you are almost guaranteed to get some deformation of a rotomolded boat on a long hot day. Much of the time those changes are reversible, but there are a few plastic boats that I see around here, always strapped to the car, and you can tell that they are considerably hog-backed (the bow and stern are sagging), and I doubt there’s any hope of correcting that.
thanks Nate
I was trying to describe longterm damage to plastic boats and “hogbacked” is a good word… I also like
“banana boats”.
Either condition seems pretty well permanent.
Of course w. J-cradles atop his big vehicle, the OP will have to give up garage parking for the season
'-)
good bananas and bad bananas
Banana boats can be a lot of fun, if they banana in the right direction! 
Regarding garage clearance (without the boat), it’s probably worth it for a tall vehicle owner to pay the extra few bucks for the folding J-carriers. I got the Thule 835 on sale from my local retailer for $140. Not quite as cheap as the basic J cradles, but a small premium to pay for being able to go through the bank drive-thru without getting stuck.
We have
Two things to watch out for on a warm day - oil canning where the boat is supported below, and meltdown on the ends if you use bow/stern tie-downs and leave them too tight. We never had the latter issue, but we did see a plastic boat coming back from Maine on a hot day that had achived a U in the wrong shape.
But if you loosen the straps and shift the boat around while it is parked, like once you have gotten into he garage, it’ll reduce the issue. Just make sure you remember to tighten them again before leaving.
Priorities
After you’ve enjoyed the heck out of your first kayak, you’ll no doubt start looking at bigger/faster/shinier kayaks, which may cost more than your car.
If you have your priorities straight, the question soon becomes, “How long can my old clunker car continue carrying my kayaks?”
Good luck!
Delphinus
http://www.AquaDynology.com
good bananas
me likee very rockered boats 
my NorthShore Shoreline Fuego is very fun.
but I’ve seen some Tsunami bananas that, while exotic by name, were a bunch o’ trouble for their owners '-)
Thanks!
Thanks to everyone that’s replied thus far. Deformation is what I was worried about, so I’ll look into some J cradles, and try to minimize the sun contact and strap tension as much as possible when it’s appropriate.
I agree with Doug that the cost of the cradles is relatively minimal compared to the kayak, so don’t mind that purchase.
I hadn’t thought too hard about the theft aspect, but I suppose that’s a genuine possibility as well, but it’s probably one of those variables I’ll just have to take the appropriate measures to deal with and hope for the best.
Thanks again for the advice.
Mike
Get a Kryptonite cable from
some place like HD and fasten it though the boat or tightly around it and lock it to the car rack.
Measure your clearance
If you can park it under a roof, that’ll solve the problem as well as making the car interior more comfortable for you to get in. It will also reduce UV damage.
I don’t think it’s just plastic boats that suffer from deformation under very hot conditions, either. Last summer or the one before that, someone in the Seattle area reported that his glass kayak became deformed while rooftopped during a heat spell.
KryptoCable x2
One of these and a big honkin’ key padlock allows you to lock as many as 2 kayaks to your roof rack:
https://www.kryptonitelock.com/products/ProductDetail.aspx?cid=1001&scid=1001&pid=1124
http://www.masterlock.com/apps/catalogimages/orig/930dpf.jpg
Most cradles allow you to thread the cable through them too, if need be, though you may need to link two cables together for extra length.
Like any security system, a determined thief with enough time and know-how can always defeat it, so it’s mostly a matter of making his time investment and risk too costly. The above setup has prevented our two mountain bikes from being swiped off my car rack at least once, and so far has worked for our kayaks too.
Good luck!
Delphinus
http://www.AquaDynology.com
Correction
The question should have stated …
How long can I leave my car attached to my boat?
Touche!
Like Delphinius pointed out, I’m obviously a newbie, and have my priorities backwards. 
I’ll work on that.
So, you’re doing flat slow water
How about a short boat that will fit inside. Do you need to leave seats in for family? Nah, they can buy their own van and boat. Have you looked at foldables and inflatables?
Good points, but…
Yes to the flat/slow water for the most part. No, I actually don’t need the seats if I’ll be hauling the kayak during the week, as those are nights I’d be sans kiddos anyway.
I had briefly considered folding and inflatables, but my size (6’4"/290) tends to make me think that those probably wouldn’t work all that well.
Mike