To Seal or Not to Seal?

[Looneytoons]

I am building the Kuffel Creek Cubby.

The trailer will be covered with aluminum. The plans do not call for the sides and roof to be sealed. However, they do call for the outside walls to be covered with contact cement prior to installing the aluminum sides.

My question is, should I:

1) Not seal anything?
2) Seal the outside of the wall and roof?
3) Seal the inside of the wall and roof?
4) Seal the edges?

Also, as I understand it, I should not seal any of the surfaces that are going to be glued. Correct?

Finally, what product should I use to seal the appropriate surfaces?

[planovet]

I would seal both sides and all 4 edges of every piece of ply, but that's just me.

I would suggest using CPES. It's a good product with a good track record on this forum. It's a little pricey but good insurance against rot.

I floated my aluminum but I would still seal even if you are gluing.

[madjack]

I seal everything...especially edges...I believe the Kuffle Creek plans call for no underlayment...something I do as well...as far as the side go, I float them as well, relying on the fenders, door and roof trim, etc,etc to hold them in place...contact cement can work and many have used an adhesive meant for securing outdoor carpet to a outdoor deck..........
madjack

[Ageless]

Having torn down several 30 - 40 year old trailers; the looked structurally OK, the inside of the Aluminum was shiny; the untreated wood? Dry-rot!

Just one small spot where the trim fails to seal is an entry point.

Seal everything!

Having worked with contact adhesives for many years; it actually holds better on epoxy sealed wood (sanded) Than on bare wood.

[madjack]

...here is a link to the Henry's product clicky clicky this product (and similar) was quite popular around here for a while......
madjack

[Looneytoons]

If I decide to use CPES, should I treat the surfaces that are to be glued?

In other words, will Titebond III or a polyurethane glue bond to a CPES covered surface?

[madjack]

..titebond will not...polyurethane will(rough up the surfaces to be glued)....................

[eamarquardt]

CPES is not cheap and comes in two quart and two gallon kits. How many square feet can you get (say on plywood) per quart of liquid?

Thanks,

Gus

[Looneytoons]

According to the Rot Doctor website, you can expect somewhere around 300 square feet per gallon on new wood.

[madjack]

...keep in mind, it will take at least 3 coats to properly seal using CPES...maybe more on edges....

[Wolfgang92025]

CPES is not cheap and comes in two quart and two gallon kits. How many square feet can you get (say on plywood) per quart of liquid?

Thanks,

Gus

Gus,

When you think about the time and money already spend on building your trailer, the cost of the CPES is relatively cheap over the expected live of the trailer, if it prevents the wood from going south on you.
As for applying CPES, on a nice warm day you should be able to put two or three coats on in a day. I found out if you mix a bigger patch then needed, just cover the container in foil and it will keep for several hours without a problem.

Wolfgang

[Arne]

I did the cpes after I did the gluing and assembly. Maybe I'm wrong, but I figured if I cpes'ed all the exposed edges, I would get anything that water to get to.

The walls and roof got 2 coats, the roof edges got extra attention. Those were the only exposed end grains.

[Looneytoons]

I did the cpes after I did the gluing and assembly. Maybe I'm wrong, but I figured if I cpes'ed all the exposed edges, I would get anything that water to get to.

The walls and roof got 2 coats, the roof edges got extra attention. Those were the only exposed end grains.

I think that's the way I'll do it. The glued areas should be waterproofed by the glue itself as long as I'm using a waterproof glue, correct?

The Cubby roof is aluminum over the insulation so nothing to treat there. The hatch does have plywood under the aluminum.

Will I be able to get by with a gallon?

[aggie79]

The 300 square feet per gallon converage is pretty optimistic.

I bought the two-gallon kit and used almost half for three coats on the floor of my teardrop which is a little less than 5 feet wide by 9 feet long.

[alffink]

LooneyTunes

Read Kevin's instructions, regarding the contact cement, carefully.
The sides and roof are intended to float, only use the contact cement on the wood surface, it will aid in placeing the aluminum, but will allow the aluminum to float free after just a couple of temp changes. If glued per the directions on the can, the aluminum may not break loose and you could run into problems when the aluminum wants to expand and the plywood does not.

Just my thoughts, others may see it differently