How to Build a Boat Out of Ferrocement

Learn the basic steps of building a cement boat. It's easier than you think.

| July/August 1972

  • cement1
    Wood strips are nailed in place over the skeleton of the boat's hull.
  • cement2
    Any depression or bulge in the developing hull must be leveled.
  • cement4
    With enough people, you can plaster the boat's hull in just a few hours.
  • cement3
    A layer of polyethelene is applied over the wood planking.
  • cement5
    Once poured, the cement must cure. This can be done by covering the hull with moist blankets for 28 days.

  • cement1
  • cement2
  • cement4
  • cement3
  • cement5

Building a concrete boat may sound pretty freaky . . . but it works and the job is easier than you might think. The finished craft has some real advantages over conventionally constructed boats too: it won't rust or rot, sharp rocks don't punch holes in it and the vessel just keeps on getting stronger for the next 30 years or so!

What you do is build a wooden frame in the shape of the boat you want, tack on several layers of chicken wire and metal rods . . . and then cement over all your mistakes (you'll have a lot more leeway with this process than if you were working with wood or fiberglass). Once the reinforced or "ferro" cement sets up, you'll have a seaworthy hull that's both dirt-cheap and virtually maintenance-free. And, if you keep the thickness of the troweled-on pour of cement down to less than an inch (which provides plenty of strength), the shell will weigh about the same as a similar hull constructed of wood.

The ferrocement process seems ideally suited for that large boat you never thought you could afford. Pool your spare change and weekends with a few friends and you can build the hull of a 36-foot fishing boat in 700 man-hours for a materials cost of less than a grand! Or bring in a 50-foot work boat hull—with deck and bulkheads—for less than 2,000 man-hours and about $4,000.

This all sounds pretty implausible and it was . . . until the idea of constructing watercraft from concrete was rediscovered in the 1940's by an Italian engineer named Nervi. The concept was later picked up by some New Zealand experimenters and brought to North America by John Samson when he established a ferrocement design and supply business in Canada. Several hundred—if not thousand—such vessels have now been launched or are currently abuilding on this continent.

Almost any watercraft—sloops, ketches, cutters, power cruisers, tugs, trawlers, houseboats, you name it—can be built from ferrocement. If you're boat-wise and already know something about this construction technique, you can probably adapt regular boat plans to the process. Otherwise you may want to buy drawings and instructions tailored specifically for ferrocement.

Yes, it seems certain that ferrocement boats are here to stay . . . still, a few words of caution are in order before you dash off to "pour your own".

8/30/2014 10:48:00 PM Stronger lighter concrete with far less environmental impact to produce here is a source Happy building!

Mother Earth News Fair Schedule 2019


Next: February, 16-17 2019
Belton, TX

Whether you want to learn how to grow and raise your own food, build your own root cellar, or create a green dream home, come out and learn everything you need to know — and then some!


Subscribe Today - Pay Now & Save 64% Off the Cover Price

Money-Saving Tips in Every Issue!

Mother Earth NewsAt MOTHER EARTH NEWS, we are dedicated to conserving our planet's natural resources while helping you conserve your financial resources. You'll find tips for slashing heating bills, growing fresh, natural produce at home, and more. That's why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.95 (USA only).

You may also use the Bill Me option and pay $17.95 for 6 issues.

Canadian Subscribers - Click Here
International Subscribers - Click Here
Canadian subscriptions: 1 year (includes postage & GST).

Facebook Pinterest Instagram YouTube Twitter flipboard
Free Product Information Classifieds