VCP hatches and holes in bulk head

I have heard that some people drill small holes in their bulkheads in order to relieve the air pressure that can build up and pop of VCP hatches while car topping in hot weather. I have one opinion in favour of this, but was looking for a couple more before I go drilling holes in my boat. I am concerned about this because I will be driving across the country this summer and expect to put in some long days on the road.


Why not?
This is only a potential problem when the temperature has increased since the hatches were last sealed but why worry about it - just drill the holes. They won’t hurt anything. I used a 1/16" bit and put the holes about 3/4 of the way up from the bottom. The only way water will ever get near the hole is if I swamp, and it takes a long time to get more than a few drops of wather through such a small hole.

Check first…
as many boats come with pin holes in the bulkhead…

VCP hatch covers
Drilling holes is one soultion. Removing the hatch covers and putting them inside the copmartments is another.

Drill? anybody ever use a hot pin
seems to me that that would be enough.If I drilled I would use the tiniest bit I could find and drill in the middle. Might be a nice telltale if you holed your boat. Drill at the top and your compartment would have to be totally full before there is any water in your cockpit. not good.

I’d vent them
I read on another BB about some guy that took his boat over a mountain pass and damaged his boat from the change in pressure, The hatches stayed on, i believe it was the bulk head that gave way. I don’t recall the boat make, but it was a glass boat with Valley or Kajaksport hatches. I vented mine on the Explorer, Cool spring mornings and hot afternoons made the hatches bulge like mad, but they never popped. It was always a worry while paddling and they looked like they could go any minute and I could not reach to vent them.

Drill near the middle
If your boat is upside down and you drilled on the top, the vent hole is now on the bottom and will allow a small amount of water to pass.

My Gulfstream came from the factory with the bulkheads vented in the center. My hatches don’t bulge or tend to implode from temperature differentials and there is very little water passing through the holes when my boat is upside down or rightside up.

No problem with drilling
a small ventilation hole in the bulkhead. Valley boats do not come with this like P&H or some other brands. I’ve gone the other route and kept my bulkheads completely sealed. I take the hatch covers off when transporting the boat on my car and pull up a corner of the hatch covers when the kayak is parked on a beach to keep any pressure from building up. Seems to work well for me.

Good luck.

Not a kayak, but…

– Last Updated: Jun-16-04 1:44 PM EST –

I built a small catamaran a while back. It was cold the day when I buttoned it up and left the shop. I parked it outside and a few days later returned to find that the weather had warmed and one hull was distorted, it looked like a balloon. I had neglected to drill a vent hole in that hull and the expansion had done considerable damage to the boat...

This could be the cause for some of the leaky bulkheads in kayaks
If it's enough preasure to buldge hatches, that same preasure is also pushing on your bulkheads.. GH

BTW, I just checked my CD(with factory vents in the center of the bulkhead)as I had it out for a practice session this morning. It had been filled and emptied about five times and then hosed out. The only thing I found was a little dampness in the rear compartment.

As recommended to me
NJPaddler’s approach is what Tom Bergh recommended to me.

Opposite Condition
I think a more common problem is putting the warm kayak in cold water and the air in the compartments contracts causing a difference in pressure that could suck rubber hatches inward and/or cause oil canning of the hull and deck. The same solution applies - burp the hatches or provide some type of venting.

I vent the bulkheads in all of my boats

– Last Updated: Jun-22-04 4:03 PM EST –

Interestingly, one side benefit is that they tend to stay drier inside. The only explanation I can come up with is that when the air pressure inside unvented compartments drops, it will draw in air and/or water from any available leak point. With vented bulkheads, that won't happen.

BTW, I drill the holes (1/32") ~1" above center. The theory is that if the boat is upright with me in it- say after a re-enter and roll - the water level could be above center. When the boat is inverted, it's unlikely that the water level will be anywhere near that high. Honestly, I'm not sure that it really matters.

What about the cover seal?
I’m pretty new at this, so forgive me if this is a stupid idea.

Most of the hatch covers that I see are simply made of rubber - not unlike a Tupperware lid. Could you just do something like drape a wire over the seal - so that half the wire is in the hatch, and half hanging out - which would cause the lid not to have a tight seal?

My kayak is brand new. The thought of drilling through it gives me the willies.

A tiny hole
in your bulkheads is a good place to get over the “willies” with a new boat. Very little chance of messing it up or doing any harm (and a dab of sealant would plug it if for some reason you did).

Locate hole center of bulkhead or a bit above as already recommended - and go for it.

Most kayaks can benefit from some minor work/adjustment/improvements/customizing. This small step will get you over the reluctance to work on it. Will also make minor repairs (yes - stuff happens) less intimidating if you’ve already done some other things…

This will cause you to get a lot more
water in your water tight compartments. Every breaking wave will add a little bit.

A tiny hole in the bulkhead will not pass any water unless you get water in the cockpit.

If I am practicing rescues, at the end of a day, I may havejust a couple of ounces of water inside my hatches. Not enough to worry about.

The opposite side of the aisle
I don’t vent any of the 9 (soon to be 12) bulkheads in my NDK boats. I like the way the hatch covers suck-in or bulge-out. It’s a simple and readily available indicator that my compartments are still air (and hance, water) tight. Once the covers no longer react in this way I know it’s time for some repair / maintainence.

When my hatch covers perform as above the hatch contents stay dry as a bone. Once the covers no longer react that way there is a least a little water getting inside. I like bone dry hatches. You don’t protect a containor’s ability to seal by putting a hole in it.




– Last Updated: Jun-25-04 4:32 PM EST –

For the input. I was a little shy about drilling because I had just purchased my Legend, but since installing the compass I no longer have that little phobia, so i'm just going to drill away.

Just remember: don’t drink and drill

– Last Updated: Jun-25-04 8:35 PM EST –

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