Interior Wall Materials

Discussion in 'Materials' started by mnmc, Feb 29, 2012.

  1. mnmc
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    mnmc New Member

    Hi all,

    I'm looking to renovate a steel-hulled motor yacht (26'x110') with 6 guest rooms. The exterior walls are steel, with the interior seemingly plywood, with fiberglass insulation used in between. The design of the boat is good, but the interior spaces & rooms may need significant work (think: mold/mildew in the walls, poor insulation). Photo attached of one of the rooms.

    I'm curious what some of you experts would recommend in terms of materials to use on a boat like this, especially walls/ceilings/floors. It seems options include:

    - Walls/ceiling: Vinyl covered marine plywood, Painted underlayment-grade lauan plywood, others?
    - Flooring: Wood or laminate flooring (same as in a house), carpet
    - Others?

    The boat will be in a cold weather climate, so I'm also wondering if the spray-foam polymer insulation that has become popular in home construction is viable on the inner surface of the exterior steel walls (especially considering condensation in the winter).

    Thanks in advance for any thoughts,

    Attached Files:

  2. gonzo
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    gonzo Senior Member

    I think that it depends largely on the budget and the owner's expectations. You can wallpaper and trim and have a nice finish. Spray foam may work, but that would mean stripping the whole interior.
  3. Ad Hoc
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    Ad Hoc Naval Architect


    Nice boat :)

    So long as you use any suitable marine plywood or marine specific material, you should be ok. Some, of course, are better than others...which depends upon the size of your budget.

    If you're in a cold weather climate, ensure you have plenty of ventilation, and use solid insulation material. Use something like Rockwool or Firemaster with a min rating of around 40~50kg/m^3 and around 100mm thick. That should provide you with plenty of good insulation. An air gap helps too, which helps to also collect any condensation in "run-offs" too.

    So, depends upon your cost, and time frame for build.
  4. michael pierzga
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    michael pierzga Senior Member

    The boats I work with use spray foam. 100mm would be nice but not always possible. Do research on foams..all foams are not suitable for marine applications.

    Do careful planning before you foam. Assemble all cabinetry , then disassemble and foam. Dont bury plumbing or cable runs under the foam. Dont use spray foam in areas that may get wet. Use closed cell sheet foam or other insulation. .

    mask off any areas in which mechanical fasteners will be needed or future access will be needed..

    Plywood is used for interior work.

    Foam core plywood is expensive but needs much less frame work, stiffening and is worthwhile for many applications.

    Attached Files:

  5. mnmc
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    mnmc New Member

    Thanks for the responses, gents! Helpful indeed.

    Any thoughts on how to learn about this topic? i.e. how to design and do this sort of work? I sure wish there was some sort of apprenticeship program one could get into.
  6. keysdisease
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    keysdisease Senior Member

    Depending on where you are in the States, you might be able to sign onto a refit job like you describe thats underway. Plenty going on here in South Florida.

    On a 110' yacht an interior designer can be of value regarding methods and materials. Also, blind fasteners and velcro are very common for attaching finish panels to interior walls that can be removed to access cable and plumbing.

    As well as the already made comments, is the vessel being refit to any class? That may dictate some of the materials you could (or could not) use.

    There are also partition wall "systems" like wisper wall you may want to look at, if for no other reason to get some ideas.

    If privacy is important then what level of noise control would you be looking for?
  7. CatBuilder

    CatBuilder Previous Member

    One thing to remember when in condensation prone areas of the world is that you want every surface smooth and able to be cleaned down to a microscopic level.

    This means no carpet, no vinyl over something else, no places for mold to grow.

    Don't think layers, unless the layer is varnish or paint.
  8. michael pierzga
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    michael pierzga Senior Member

    Construction of yacht interiors is straightforward. What is not straight forward is system runs, electrical runs and proper access to all of the infrastructure like tanks, bilges, storage....

    Youre best advised to carefully plan , install all systems and infrastructure first...then commence interior work

    The actual interior design , ergonomics and style, is a whole profession. Consulting a specialist would be a wise move and will save you great time and money.

    Interior components are always built off the boat in a workshop ,as modules , then transported to the boat and installed prefinished.

    If the end use of your boat will be commercial..charter... regulations will need to be should first contact a naval architect before doing anything.
  9. mnmc
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    mnmc New Member

    Keysdisease: Thanks, those are helpful leading questions and advice. Noise wouldn't be a major issue.
    Catbuilder: Good to know, thank you.
    michael pierzga: Good to hear that advice. Most of the systems and infrastructure is already in place, so am mainly looking at refurnishing or replacing interior work.

    The boat is old (i.e. 1940), so it apparently falls into some unique category with the Coast Guard ("super yacht" was what I was told).
  10. michael pierzga
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    michael pierzga Senior Member

    The interior of a yacht rests on the " floor" or cabin sole Put careful thought and detail into the floor before constructing the interior.
    Noise, movement, rigidity , access......

    Headliners are another important detail. Devote considerable thought to headliner, ceiling installation
  11. mydauphin
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    mydauphin Senior Member

    It is more a matter of what not to use. Over the years I have found these on boats don't use them:
    Acoustic ceiling tiles
    Non-marine plywood, except in cabinetry
    Most types of foam
    Home electrical wire or panels

    I also am very careful from a fire point of few. Before considering any materials I put a blowtorch to it and see if it catches on fire. I almost burn down a boat because of a little piece of Styrofoam that a spark fell on it.

    Then you have mold growth, condensation and ventilation, never an easy problem.
    Build the interior leaving gaps between interior and exterior. You can fill these with foam but remember in the future you might want to get in there for inspection and maintenance, the foam will just get in the way. I would treat and paint hull, leave it like that. Just keep your interior away from exterior. You have a big enough boat that losing 6 inches on the sides is not going to kill you. Let it breath.

    Ventilate your bilges, take the colder air out of there, move the air from top of interior.

    The first thing I would do is open a big hatch in the middle of the boat (or somewhere easy for moving stuff around ). It needs to be at least 4' x 4'. Remember you are going to be moving a lot of stuff in and out. Best if you can move prebuilt pieces in and out, or at least sheets of plywood in and out.

    Also remember, some of those walls are bulkheads, do not remove these. They are there for a purpose.
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  12. mnmc
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    mnmc New Member

    OK, thanks for the tips.
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