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Anke and I live aboard WAYWARD, and wrote about it's design and construction at

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Fair winds!

Dave and Anke
triloboats swirly gmail daughter com

Friday, December 1, 2017

Pop Up Tents

Commercial Pop Up TentsFrom springwire... toss in the air to unfurl

Live in the sunshine
Swim the sea
Drink the wild air
-- Emerson

Pop-Up Tents

Most of the barge/scow hulls in the world have wide open decks, with hatches as needed. Why? Cheap and flexible.

Most of the yachts in the world have fixed, trunk cabins as superstructure with fixed, furnished interiors. Why? Um. Well... at a guess? Tradition? Laziness? We're all wannabee ocean crossers? Harder to say.

Trunk cabins and furniture break up the open spaces and limit our options. True, they don't have to be set up at the end of a long day. Or in the rain. Or in the dark. In our boats, we've always chosen this style, but only after a good deal of waffling.

Of course, a mix is always an option. Just because we're designing box barges doesn't mean we have to stay in the box!  An aft trunk cabin, say, with the whole forward deck flush and extensible is entirely possible.

So let's take a look at open deck, flexi-space architecture, extended by pop-up tents. Here, I'll present three types I find especially attractive.

Hatch Cover Tent

This approach, shown on my T24x4,6,8 SANDBOX design, simply tilts the midships hatch up, then puts a custom fabric shell over it. The flap, shown, ties to the gallows to provide a vestibule of sorts.

The idea is to work with existing hatches, using the covers as structure for the fabric shell, and the hatch coamings as landingss for it. One could cant the hatch cover, as shown, split it in two for side walls, or raise it at both ends for a more horizontal roof.

Supporting struts for the hatch require a little ingenuity, but nothing others haven't solved for us, time and again.

Pram Style Tents
This one from check 'em out!

Pram style tents have hoops that go to a common point, and rotate around that point. They can be fully or partially erected for anywhere from stowed flat to full coverage.

Hoops don't have to be round, as shown here... they can be more or less squared off to clear rectangular hatches when stowed (with maybe a little arc on the upper edge for rain shedding).

These have been used on boats very successfully for small hatch openings (JESTER pram hoods by 'Blondie' Hasler and Scott McCleod), and for large, open spaces (TIKI tents by James Wharram).

Advantages are quick and easy set-up, many intermediate positions and fold-flat for low windage.

Lightweight Emergency Shelter
by Patrick Wharram
This third approach is by Patrick Wharram (no known relation to James Wharram). It's superficially similar to the pram approach, but the lower hoops do not go to a common point. This allows a longer run than is possible with the pram.

Alongside a hatch, a pair of tracks can guide slides at the bottom of the hoop Vees. This can be extruded aluminum or DIY wood T- or C- track. Like the pram style tent, this can be erected fully or partially, depending on conditions. Again, hoops can be squared off if desired.

Framed Structures on WATERPOD
Note fabric biminies and domes on framed structures

Here we see a fairly complex set of frames that spread fabrics along over the decks of WATERPOD. These can range from very simple to very complex (the actual build sports a geodesic dome!).

Frames can be multi-purposed to provide security for the crew, mount solar panels and other gear, even support rigging. Fabric can be stretched over set frames in different ways, depending on conditions.

Here's another example... a fishing boat from Lago Maggiore, Italy:

Trailer Style Pop-Ups

An intriguing option, especially for boxy hulls, are types that fold up and out of the box. They can be either hard topped or soft:

Hard Top

Soft Top

Note that platforms can be folded outward (possibly from under the hardtop hatch). They can fold fore and aft, and/or outboard. If outboard, consider inflatable flotation under their open position, where necessary. Windage will be high!


So lots of options, not to mention just setting up a regular old tent on the flat deck.

Pop up tents can be tailored to the weather... open and airy in the heat. Cozy and insulated in the cold and wet. They may be aided and abetted by pop up or inflatable furniture - chairs, loveseats, tables, bunks and shelving - all deployed and arranged for the needs of the day.

Flexible spaces for changing needs.


  1. Autarkia's aft trunk cabin which is large, multifunctional and with standing headroom would work I think with such a flush deck forward instead of the trunk cabin. If built the same size as Autarkia you could have a deck 11 feet by about 20 feet. You got me thinking smaller deck hatches over which low tents could be erected as separate spaces, allowing standing headroom when standing in the hatch, and then using the deck as a sleeping platform. A Cubic Mini wood-stove in each space equipped with chimneys that can be detached and stowed underway could allow for cosy and warm spaces. Food for thought... I might draw it up with SketchUp...

    1. Hi Alan,

      The possibilities are endless!

      I've seen mylarized bubblewrap insulation incorporated in some tents to improve that coziness factor.

      Love to see what you draw up!

      Dave Z

  2. Been cogitating on a tent for my (new to me) Wharram Tiki21. The 6'x7' platform between hulls just begs for one. Leaning toward the pram style - it would be nice if it stowed itself.
    On a slightly different tack - also planning to build your "Not a Gull" as a tender for that cat.

    1. Hi Doryman,

      I was under the impression that Wharram supplies a tent plan for the TIKI 21. We got to sail on a TIKI 26 that had a pram tent that looked totally skookum. As I recall, the owners said that too was specified in the plans. So might want to check with James and Hanneke.

      Glad NOT-A-GULL appeals! We sure enjoy ours.

      Dave Z

  3. The big question for me would be "what do I want to do with the craft?" The big appeal on a flat deck would be for cargo, while the permanent deck house is optimized for human comfort. From the RV world, the pop up tent campers would be a close equivalent, as they fold up so a small car can pull them and better gas mileage. The cons are mostly when it rains, and having to fold up a wet tent, which can't dry out until you can set it up again in a dry location. Might not be much different from sails though in that regard. However if it was set up like a convertible car, where the cover can be left up while sailing in poor weather, but lowered for good conditions or cargo loading, that would be different.

    1. Hi Dennis,

      Yeah, rain definitely puts a damper on fabric! Rainflies help somewhat.

      That, to me, is an advantage of the Pram and Instant styles... they live on deck and fare pretty much as a sail. If setting up wet, a sponge would help.

      Dave Z

    2. Having no small experience with terrestrial "alternative living" in SEAK (year-round), I DON'T fancy putting up and taking down a wet shelter in that setting. Other locales, maybe ok, but not there, especially when I think of the additional challenge in doing this on the water.

      The chief reason for the "shantification" over the cockpit deck area of the Kairos directly rises out of aforementioned experience with how easily rain water in the Cool Temperate Rainforest gets into everything unless carefully controlled. Because the boat is to be our main living quarters, and mostly sailed short ranges within specific "home base" locales, we are willing to sacrifice some sailability (substitute an appropriate synonym from the maritime tradition here as desired) for keeping rain from following directly on a livable outdoor area.

    3. Hi Peter,

      Sorry, missed this comment somehow...

      We agree, a permanent shelter is a fine thing in rain country. But we are attracted to a tent to extend that space, if for no other reason than those times we'd like the 'outside' space open to the sky (Anke, especially, likes the wind in her hair).

      The micro-cruiser we're building is half-BIRDWATCHER cabin (fixed shelter) and half rowing cockpit, convertable to a platform and tentable using sails.

      Should have some first-hand experiences to report, soon!

      Dave Z

  4. Posted on behalf of JOHN:

    One possible advantage to a permanent deck house, vs a deck tent, is that the deck house could provide additional top-side buoyancy -- helping to prevent, or recover from, a knockdown or capsize.

    1. Hi John,

      Excellent point, which I should know but had escaped me!

      Dave Z

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