Install a Top-Up Valve

Note: This page is shared between several different instructions sets. When you’re finished here, use the “back” button to return to your specific packraft instructions.

Why add a Top-Up Valve?

A top-up valve is not a necessary addition to a DIY Packraft because you can regulate the air pressure in the tubes by adding or releasing air through the Boston valve (the main inflation valve) without going ashore, but a top-up valve makes it more convenient.

A top-up valve is also a good alternative to a Boston valve as the primary inflation/deflation valve in a smaller inflatable, such as a packraft seat or inflatable foot rest, because it’s a smaller and lighter valve.

Top-Up Valve Placement:

One nice thing about making your own packraft is that you can customize it to fit your body. The ideal location for a top-up valve will depend on your body size and flexibility, but one possible location is shown below on an old V3 model DIY Packraft:

I recommend waiting to install a top-up valve after your packraft is otherwise finished, because then you’ll be able to paddle it and practice twisting your body around to find the perfect location for your valve.

If you find it too awkward to twist your body around while sitting in the boat, an alternative placement would be on the inside of the cockpit near where your face ends up when you bend forward (i.e. close to your knee, but not so close the valve will poke your leg as you paddle).

Another option is to add a length of hose between the valve stem and the tip so you can easily reach it with your mouth while sitting in the packraft.

If you like, you can use field repair tape or something similar to hold the valve in place while you experiment with different locations on the water.

Wherever you decide to install your top-up valve, make sure your elbow won’t hit it during your paddle stroke!

Top-Up Valve Installation:

Note: The white and black valve should be glued into the flexible stem with Seam Grip+WP or Aquaseal, after roughening both surfaces with sandpaper or a knife. This can be done at any time before, during, or after the valve stem is installed.

First, seal an oval of fabric to the valve with the valve stem poking through a hole in the center, and then seal the valve and the patch over a small hole cut in the packraft’s tube.

Here’s a picture sent by Jeb T. showing his top-up valves mounted in fabric rings, ready to seal to the packraft tube fabric:

If you haven’t installed an airtight zipper in your packraft, you will not be able to heat seal the top-up valve in place from the inside of the tube after the boat is complete, so you will either have to install the valve before the rear-center seam is closed, or just heat seal the fabric oval to the packraft’s tube.

Installing a top-up valve in a packraft seat or other inflatable with the TPU on the inside of the fabric:

(These same steps can be used to install a valve in a packraft with the TPU on the outside of the fabric – you will just have to flip the valve around so the stem is on the outside of the boat.)

Questions? Please post a comment below!