Repairing steel hull for 40' houseboat

[kristen]

Dear readers, I need to completely repair my 40' flat bottom steel houseboat hull-and she has a bottom full of spray styrofoam insulation that was supposed to keep her afloat but is now leaking through. What are your best ideas? I am thinking that I will have to completely replate her. Thanks, Kristen

[gonzo]

Re plating is the best solution. There are patches that will last more or less. Cement, for example, can be a quick fix. The foam, if it was sprayed, was probably urethane. Where was it sprayed to supposedly keep her afloat? They should've coated the steel with some corrosion proof material to keep it from rusting.

[kristen]

Dear Gonzo, thanks! Yes, it was sprayed to keep her afloat but nothing was done to her hull prior-she was sitting in the water. I am going to completely re-do her bottom. Do you recommend a particular thickness of steel? She will be moored in brackish water in Florida.
Kristen

[gonzo]

The thickness of the plating depends on the framing. Usually, unless there was a problem, hulls get re-plated with the same thickness. Houseboats are not so weight sensitive, specially the bottom, so you could go thicker. If you are planning on keeping her, Corten steel is more corrosion resistant. From what you are saying, seems like the bottom was corroded and was repaired with sprayed foam?

[kristen]

Yes, Corten was the original steel used 38 years ago-the foam was just sprayed inside without hauling her out or doing anything to the hull-big mess! I plan on living aboard for many years as well as hoping to leave her for my children-so I want her to be well done for the future-Kris

[gonzo]

In that case, a somewhat thicker plating is a good idea. Also, sandblasting before coating is the best. It takes all the oxidation and contamination off and also roughens the surface which improves adhesion. There are several products to coat steel that will give you proper results. Whatever you use, it is best to stay with a single system. Mix and match can cause problems.

[kristen]

thanks!