Is ferro-cement still being used to make boat hulls?

Question

Ferro-cement was the "in" material to make a boat hull from, and my father was quite taken with the idea behind it. Time and my father have passed, and I am wondering if it is still a viable building material. thank you for your responses.

Answer 1

Ferro -cement was heavily promoted by some kit boat companies to people with the idea that 'you can build a35 foot sailboat in a day and sail off to Paradise".

It sold to many people because they didn't want / or didn't think they could build the mold needed to lay up nasty smelly carcinogenic fiberglass for a "one-of" custom sailboat; or they were intimidated by the carpentry involved in building a wood boat, or were told that good wood for boats wasn't available any more.

The marketing was somewhat disingenuous, because you have to build a pretty complete 'armature' for a ferro boat; re-bar, mesh and chicken wire all very carefully, with infinite patience, bent and shaped and tacked together to hold the cement.........by the time you've done that you've done 90% of a fiberglass mold, and used the same skills needed to lay up 90% of a wood boat.

There may have been advancements in the cement over the years, but it used to be that you had to mix and trowel on ALL the cement at once ; if you let part dry and came back the next day you would never have a good bond between the areas and problems down the line.......so you needed to get a dozen people together after you put in the 500 hours to lay up the mold for the cement.

This lack of bond between old and new points out the fatal weakness to ferro.......it is hard, bordering on impossible, to fix a hole or a crack or a leak. When you get a leak, the iron in the hull rusts, expands, cracks the cement, bigger leak, more rust......etc.
It is also a challenge to attach the interior to the hull as you cant screw anything to it and expect it to stay.

MANY people were conned into the concept, and many people started and I'll bet no more than 20% of ferro hulls that were started ever launched, leaving a lot of wasted money and broken dreams behind.

The other thing that companies that wanted to sell you the ferro didn't point out is that the hull of a sailboat is about 25% of the total cost; sails, masts rigging, engines, tanks, water and electrical systems cost the same whether a hull is glass or wood or steel or concrete.......so they told people they could build a world cruising sailboat for 1/2 the cost ....what they didn't emphasize was that was 1/2 of 1/4......and the 'savings' on a hull that is problematical to fix and has a bad reputation and virtually no resale value as a result is somewhat penny wise and pound foolish.

There are still companies flogging this product out there and a google search will find them.......see if they have addressed the rusting/lay-up/repairability/ and re-sale questions. I myself wouldn't touch a concrete boat with a barge pole, unless I was looking at a static houseboat to tie to a pier somewhere and throw away after 20 (maybe) years

Answer 2

If made by a professional, the concrete hull has lots of advantages over its FRP cousin. The concrete gets harder as time goes on. The first one made in the 1860's is still afloat. Cement does not blister or delaminate. The weight can be a read advantage when sailing in choppy seas as it will plow through waves that will stop a lighter vessel. If one should encounter a situation that would hole a FRP vessel, the ferro will cave in like an eggshell. Kick it back in shape, slap some fresh cement on it and off you go. Down side is dealing with marinas. They think that you will come flying into your slip and destroy the dock. As long as you are aware of your extra weight and adjust your maneuvers there should be no problems.

Answer 3

I don't believe any production boats are being built with ferro-cement. The hulls were good for about 25 years then they started to flake. They are however still available in kits. maybe this URL would help you...www.ferroboats.com Jim

Answer 4

1

Answer 5

I have heard that they might be. There is a good website with lots of information www.ferroboats.com

Answer 6

no