Roof coating
 

Roof coating

Started by junkman42, August 13, 2008, 07:21:46 AM

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junkman42

I want to coat the center panel on the top of My MC7.  Does anyone have a suggestion such as cool seal etc.  I want it to be white and a sealant.  When custom coach did this unit they chould have done a far betster job on the roof.  Add looking at the roof when You go to buy a coach to the inspection list.   

oldmansax

I used Kool Seal on mine with good results.

TOM
1995 Wanderlodge WB40 current
1985 Wanderlodge PT36
1990 Holiday Rambler
1982 Wanderlodge PT40
1972 MCI MC7

Lin

I just did mine with Kool Seal.  I used something else in the past on my last bus, but I found that Kool Seal seams to be the only one that actually recommends it for use on motorhomes.  I have found these coatings to be extremely durable, reflective, and excellent sealants.  Kool Seal says to use two coats.  I had so much of the 5 gallon can left, I called their tech support and asked about doing a third coat.  They told me it was unnecessary.  They said that it should last this way for 10 years.  I will hit it again before that though.  I also coat the AC covers when doing the roof.   It stops the sun from eating them up too.
You don't have to believe everything you think.

Dreamscape

I bought mine roof seal at Home Depot, white and elastomeric , been five years now. ;) It needs another coat to whiten it up, but other than that I'm very pleased with the three coat results. Going to do that after the paint.  ;)

Paul

PP

Quote from: Lin on August 13, 2008, 10:52:40 AM
I just did mine with Kool Seal.  I used something else in the past on my last bus, but I found that Kool Seal seams to be the only one that actually recommends it for use on motorhomes.  I have found these coatings to be extremely durable, reflective, and excellent sealants.  Kool Seal says to use two coats.  I had so much of the 5 gallon can left, I called their tech support and asked about doing a third coat.  They told me it was unnecessary.  They said that it should last this way for 10 years.  I will hit it again before that though.  I also coat the AC covers when doing the roof.   It stops the sun from eating them up too.

Diddo. I did everything up there except the skylights and satellite dome ;D Lots more left after two coats than I thought there should be. Worried for a while that I didn't put it on thick enough, but sure looks good.
Will

junkman42

What method did You guys use to apply the cool seal?  Brush or roller or something else.  Thanks John

Lin

We used a roller.  They recommend using a 3/4" one.  I forget the coverage per gallon and think we were a bit light on the first coat, but looked fine after the second coat.
You don't have to believe everything you think.

TomCat

When I used Kool Seal, it chalked off something terrible in the rain.

I switched to BusKote, and haven't had any problems with it chalking.

HTH

Jay
87 SaftLiner
On The High Plains of Colorado

Dreamscape

I used a roller for rough surfaces. Don't remember the size but 3/4" sounds about right. The first coat was light but 2nd and 3rd covered pretty good.

Paul

junkman42

Tom Cat, where does one find buskote?  Thanks, John

TomCat

Here ya go John.

http://www.hytechsales.com/prod2150.html

Although I intended to use the clear coat over the top of the BusKote, and still have a gallon sitting on the shelf in my shop, I don't feel it's 100% necessary.

The difference between before and after was nothing short of amazing.

HTH

Jay
87 SaftLiner
On The High Plains of Colorado

PP

Quote from: junkman42 on August 13, 2008, 08:11:15 PM
What method did You guys use to apply the cool seal?  Brush or roller or something else.  Thanks John
I was going to mask off the sides with painters tape and roll it, but because I have a lip right at the gutter line, I was able to freee hand with a brush along the top edge and under the air horns as well as around the skylights and dome. Then a 3/4" nap roller from front to rear. Almost painted myself into a corner :o long way down if you finish on the opposite side from the ladder  ::)
Good luck, Will

Zeroclearance

Jay, Thanks for posting that link.   If your coach was a dark color would you recommend the top (clear) coat?

JohnEd

Guys,

Please don't hate me....please.  I have used that Kolkote stuff for years.  I started using it when I built a replacement roof on my 73 Winnie.  That roof is curved and ribbed and has 3/8 ply as a surface.  I bought the kool Kote stuff for a "new roof".  It consisted of a dark elastomeric (sic) coating that was rubberlike when it set up.  A few coats of that on the wood and then a wet coat and I laid a fabric the length of the roof and it took 3 panels.  That fabric then got a few more coats of black rubber and when that set I applied the white Kool Kote/ Snow Coat.  That was back in 93 and the stuff has held up perfectly.  One glitch is that you need to reapply the Snow Kote every couple years.  In Orygun the rain and climate serves to create a really serious mildew problem.  The mildew has to be removed with a scrub brush and a lot of elbow grease.  A real pain in the ...er...elbow.  I am happy with the engineering of the product though.

I have heard stories about the insulating properties of this stuff and the glass beads for quite some time.  I even called some mfr reps and asked about the insulation props and was treated to some outrageous spiels.  Things went quiet when I asked for an "R" number that I could hang my hat on.  I don't think these thousandth of an inch coatings have any R value you would want to repeat....truly.  They can't, actually.  The reduction in heat transfer is due to the white color and all the suns energy it reflects.  Not insulation.  I would prefer to spray my roof with white automotive grade white synthetic enamel and skip the mildew and semi annual repaint if I had a metal roof.  BRIGHT pure white, of course.

I needed something that would expand and contract with the wood roof and I would use that product again in a heart beat for the purpose of a water tight seal that "moves and doesn't crack.  I have 3.5 inches of polyisocy. foil backed board in my roof and a 2 inch thick regular foam sheet and 3/4(total) layer of wood.  I have no heat transfer problem of any sort and the white roof adds to the perfect solution.  Expecting that paint to "insulate" my roof would be foolish....I think.  I can't imagine a Knut not having insulation built into his overhead and roof under side and that would be the real insulation.

My original roof failure was due to the PO applying silver roof paint that cracked and leaked and my not having a clue as to how to maintain an RV.  I am still only semi smart and still semi tough only in spots.

Well, for what its worth,


John
"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
"We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light."
—Pla

junkman42

If You use masking tape can it be removed after the buskote drys or do You have to remove while the coating is wet?  I noticed that the spray in bed liner people use a tape with a wire in it that sort of cuts the edge when removed.  I only want to do this once unless it goes like most of My projects.  John