Venting Hollow Surf and SUP Boards

Venting Hollow Paddleboards and Surfboards

Atmospheric venting of hollow surfboards or sup’s is critical.  Without a functioning vent, your board will be vulnerable to structural failure due to (primarily) the expansion of air inside your board as the board heats up, which it inevitably does when out in the sun.  The amount of pressure build up inside a board can increase to the extent that the board will actually pop!  I know this to be true because it has happened to me.  Boards going from worm or hot air to cool or cold water will also create suction. The vent will relieve this pressure difference.  At first I wasn’t sure what the sound I had heard was, but as soon as I got to the launch site and looked at the deck of the board and how expanded and rounded up the deck was I knew exactly what had happened.  The board didn’t actually explode but parts of the deck popped loose from the internal framework and the loud pop I had heard was the sound made by that structural failure.  Oh man, did I feel horrible….I only had one board at the time, the surf was good and I needed this board!

I had installed two membrane (Goretex) vents and was confident that I had done the right thing.  So what happened?  The vents I had used were the Goretex membrane type.  My comments are not about how “bad” the Goretex vents are, they are about the limitations of any membrane vent.  Goretex vents will only transfer a certain amount of air through the membrane.  The board I installed them in is a redwood board and what I hadn’t anticipated with the redwood skin on this board is just how fast the darker wood would heat up.  So even with two Goretex vents in this board, the pressure built up to the point of failure….so, POW!! was the result.

The solution for me is that I now use mechanical vents which are simple screw in/screw out affairs….but you must remember to screw them in and take them out.  Pretty simple but you can’t forget either operation.  So is there a perfect solution to dealing with pressure build up and suction in hollow boards?  No! Paddlers are pilots with little on the pre “flight” check list; fin in, check….vent screw in, check….leash attached, check…pdf on board, check…that’s it…really simple! Paddle On!! 


Mechanical vent

Mechanical ventHere is a photo of the mechanical vents I like.  The brass body threads into a wood block attached to the underside of deck, usually somewhere near the tail. The block is drilled through so that venting can occur. Some builders claim you need two vents in boards over ten feet in length but I’m not buying that argument for the mechanical vents.  I can see using two vents if you are using membrane vents only, but then, I don’t think that’s a good idea.

New 14′ Hollow wooden Paddleoard kit at the Season Change

New 14′ Hollow Wooden Paddleboard Kit

It has been a hot and smokey summer around Southern Oregon this year and in some ways I’m glad to see the rains come.  But this change of seasons is the classical double edge sword.  On one hand, the hot days and the smoke from nearby forest fires has gone away for the year, but so has the beautiful summer weather and the great flatwater paddling we have on the local lakes.  On the plus side is that the newest hollow wooden paddleboard kit I have designed, a 14’er that should be fast and fun to paddle, is sitting out on the assembly table with the framework all glued up and ready to start stripping.  That’s where the season change comes into play; the lakes just aren’t as inviting when the temps barely get out of the 60’s and the sun is looking pitifully low in the sky even at mid day so it’s easier to be in the shop working on a new shape! Don’t get me wrong here; I really do like to design and build these prototype boards but the reality is that it’s hard to put in the kind of shop time required to do the job right when it’s also the time to be on the road going to races and other events that are  mecca’s for the sup paddling community.  

The new 14’er has been cut out via cad/cam cnc routing production methods, and although there are some very minor issues that need addressing  in the next production run, this should be a fun board to assemble.  A couple of things that make this board an easy build are the rocker tabs and the rail shape.  The rocker tabs make for a quick assembly of the framework and the rail shape should make the rails easy to strip.  This new 14′ board is designed for minimal surface area and a rail shape that keeps side chop off of the deck.  I’m really looking forward to getting serious into this build and getting it into the water for a trial run by the end of the year!