houseboat roof repair replace help

Hey everyone, i have a late 70's Sumerset 55' x 14' houseboat. Steel hull (before i get thrown under the bus for a steel hull, its paid off and we love it, in fact its getting all new steel put on the hull now.) Here is my question, it has a few week spots in the top roof/deck. and had some leaks etc. so i was going to put new tongue and groove plywood on the entire room. around 1/2" maybe 3/4" not sure yet. i was going to put it right over top the old room. So my questions are:
1. is putting the wood right over top the old ok?
2. What type of covering do i put over the wood? EPDM rubber sheets, epdm liquid rubber, durabak, or something else?
3. Do i need to treat the wood before hand or can i just cover it up?
4. The inside ceiling is the kind where you can see all the studs (studs are in great shape, there were laquared or something so the water has not affect them at all were the leaks where and are 2x5".) but the white panels inbetween the studs are looking bad, any ideas of how to replace the white, it looks like the white board was put on the top before the roof, so without taking all the old wood of the roof, there is no way to change it, does anyone have ideas of what i could put over the white to make it look better, or am i going to have to put up a whole new ceiling and cover up the studs.

thanks for the help.

 

Solo,

If you leave the old wood, it will leave the extra weight in place. And rotting. Always better to remove if you can.

As for roofing material, why not use [quality] radiant barrier topped with metal roofing?

Works great on homes.

IMHO.

wayne

 

Thanks for the reply, i dont think weight is a issue, i dont want to use metal, as we use it like a party top and have people up there chairs etc. i am just triing to save from ripping all the old wood up, it will be a big choir i believe as its covered in fiberglass.

 

There are several options for roofing material. Some more modern materials come in rolls that self-adhere.
Talk to your local lumber yard about flat roof material options.
I would guess the "white" stuff is just styrofoam and it's hard to make it look good without covering it. You may like the look of the rafters inside but you'd be better off covering them (and the foam or white stuff) with a sheet material or narrow tongue and groove boards such as can be found in your area for a reasonable price. Otherwise there's a lot of work fitting pieces in between rafters.

 

so what do you think about just covering up the old roof with new wood? thanks for your help

 

I don't know what you mean. Without more detail it's impossible to advise. I think you need to post some photos or describe better the exact construction. So far its a bit vague to follow. I think you're calling studs rafters. What is the condition of the existing structure (rafters, sheathing, roofing material)?
I could help but you have to make an effort to paint a comprehensive picture of what's there now.

 

yes the studs are the rafters. the rood now is 1.5" think with fiberglass coating and then some rubberozed paint stuff on top. it has 2 bad spots in it that need rplaced. sorry dont have any pics boat is 3 hrs away right now getting new bottom. we use roof as a party top so roof needs to be strong. thw inside is rafters or studs. which are visable they are in great shape but the white thin board in between rafters is not in good shape. hope this helps

 

here is a pic that i found of the roof..

 

Even on land houses rotted roof decking is removed and replaced. Old shingles can be left on and covered with new, but bad decking should be pulled.

Most of the roof coverings you suggested aren't made to handle traffic. I'd cover it with fiberglass.

 

Yeah, you definitely need to have a surface that can stand foot traffic. 1/16" rubber ought to stand up. It's used as swimming pool liner as well as a roofing material.
You could also do a Rhino liner over plywood.
With either, dark colors get hot so I'd paint a white color over whatever you use. It must of course be a compatible product.
On the other hand, a company called Henry has a roof-in-a-can product you paint on, claimed to be half the cost of a standard roof covering. I could see painting that on rubber, which is cheap ($1.00 per sq ft).
What about what lies beneath the surface? Is it plywood? You have to make sure the original plywood or (?) sheathing is sound. You asked about treating the plywood or other wood sheathing material. Yes, you can paint the wood with a preservative but it isn't strictly necessary any more than it would be on a house (Unless you are spot-applying it where you want to prevent the continuation of existing rot hiding in cracks or holes). A houseboat can be considered very similar if not the same as a house on the seashore in terms of above-water construction methods. Black plywood indicates mold and mold is the precurser to rot. You can bleach areas like that to kill the mold, Any physical damage to plywood should be removed. Sometimes you can patch in a piece of new plywood, even in the middle of a frame space, by cutting out a rectangle and taping and epoxying a new piece in using fiberglass tape/epoxy inside and out.

 

Alan, so what i am wondering is can i put 1/2" plywood over top of the old roof. and then put rubber over it? seems like it would cut out alot of work of ripping all the old wood and fiberglass out.

 

What is the original roof made of?

 

You need to remove the rotted plywood.It can " infect " the new plywood with fungus , and rot spores and will just begin to consume the new over laying plywood same as the old bad stuff.

One option is to cut out the soft part and graft in new wood , if the rot has has not spread too far.

I would not under estimate the additional extra weight you would add the over old ( plywood ).

An entire roof of 3/4 inch plywood and water proof membrane can add significant weight just where you don`t want it , and affect stability.

There is no real easy fix to this.
If it were my boat I would first try and determine how much of the roof is soft , and if it`s not too wide spread I would replace that section.

https://www.youtube.com/watch?feature=player_detailpage&v=AdR_6rw32OU



Good luck with whatever you decide.

 

the roof is made of 2 layers of 3/4" plywood and covered in fiberglass. How do i remove the old fiberglass to get to the wood.

 

The glass is probably not too well adhered to the plywood. If you saw into the old glass with a carbide blade in a circular saw making cuts that are slightly deeper than the glass and spaced a few inched apart, the glass should come up with a thick putty knife and a hammer to drive it. Rotten areas will come up easily.