Roof paint

[NewbeeMC9]

I found this site

http://www.hytechceramics.com/

got a lot of info and prices, very interesting, they work with the NASA and are in Florida.

Nellie

I added this to my roof paint when I had it painted.  I have original insulation and need any extra I can get.  Since it was getting painted anyway,the bag of ceramics was only around $60 more. So I thought I would risk it for the chance of more insulation.

[Nellie Wilson]

Hey Newbee

Thanks for the info, but you left out the punchline. .. how did the stuff work?

Inquiring minds want to know 

Nellie

[NewbeeMC9]

I had it painted white for it's benefits too so who's to say (radiant and dirt showing benefits).  No official test data and hadn't worried about it.   

There was issues with the painter so it ended up mixed in with the clearcoat, I like the traction when on top of bus but turns dirty when parked under tree.  Bleached water followed by sunlight snaps it out.

Had a thermometer sitting in there with the max needle on it. and it would only get in the mid 90's sitting in the southern sun facing north.  Again it is white.

Opinion     I would not use it in place of closed cell foam, or paint it just to add it. If I was painting the roof anyway, I would probably add it again.  I would use white.       That's mine and is not guaranteed for accuracy or longevity.


I am interested in Johns test

[Nellie Wilson]

Newbee -

Thanks for the explanation. But now I'm totally confused (per usual). I like hearing about your temp staying in the 90s, but the other stuff...?

I mean, my roof is in great shape (just scrubbed it down) but it's not white - white... more of a cream color. I've got only original insulation (in the roof) and would like an alternative to disassembling things (already built my upper cabinets, etc.) to add insulation. But other than that, I wouldn't paint it.

Shoot!  Back to the old drawing board. Or just wait to hear the results of John's tests? Yup, that's what I'll do... waiting is much easier than thinking .

Nellie Wilson

[ruthi]

Nellie, from what I am told, the paint additive was the first to come out. The stuff at TC is the latest, and it is not a paint additive. You can paint over it if you want to though. One other thing I didnt mention is it is a great sealent to, your roof could never possibly leak with the product applied. Anyhow, I dont have any investment here with what ever you decide to use, your decision,   Just like to let others know about stuff that I find that is good. Good luck!

[Nellie Wilson]

Thanks Ruthi -

I'm still leaning hard in your direction; like you, I always want to hear from 'real' folks who have tried these products... and your results sound like what I need. BTW, is that TC stuff slick and easy to clean?

Just an eccentricity, but I hate a dirty roof. Fellow asked me yesterday, "Why? Nobody can see it."

And I responded that people in second story windows can see it, and people on overpasses. And birds a and squirrels too. Guys! Just can't think out of their own little box.

Nellie Wilson

[4905 doc]

when we got our 4905 it already had a white roof.  it was late spring in florida when we started converting. you could not hold your hand on the ceiling for more than a few seconds without getting burned. cost was our concern, so we used kool-seal that I bought at the big box store. first coat... what a difference. you could touch the ceiling all day. I put a second coat on just because. figured it wouldn't hurt. 2 five gallon cans did the job. Like others have said, roof had a rough texture to it. but, it's a roof. not like you spend all day up there

[4905 doc]

Nellie, you posted as I was. guess I made your point about guy's didn't I?

[Nellie Wilson]

4905 doc -

Yup. Out of the mouths of babes...

Nellie

[ruthi]

Nellie, no, it is not a smooth surface, but, that is what a power washer is for. We always wash the top of the bus anyways. And, no, power washing it cannot hurt it.

[JohnEd]

Ruthi,

Well, I finally got around to doing my "experiment" with the ceramic paint insulation.  I am glad to report that I MUST EAT MY WORDS....sorta.  That ceramic paint actually does work.  Read on.

I have little doubt that almost anyone with a credential will be able to argue with the validity of my tests, such as they are.  For me, this is a lot like the "game" of HAND GRENADES, close counts.  I evaluated insulation performance using an kitchen oven and a 7 pound piece of 2X2 solid steel bar.  I compared the speed and extent of temp rise of the steel under different circumstances/conditions.  The temp of the oven is held to 200-209 degrees F and the time the steel is heat soaked is held to 1 hour for all cases except one.

1.   Clean bar......75 degrees at the start to 187 after a hour for a delta of 112 degrees.

2.   painted with one coat...79 to 179 delta102

3.   painted with three thick coats...70 to 164 delta 94

This clearly shows that the ceramic is in fact a measurable insulation in thin coats and that "more" is better and that also seems to be the rule of thumb in matters insulation.

I also did the same test using Isocy aluminum coated foam board.  That is te best stuff after spray foam I believe:

1.   Encased steel bar in 2inch thick close fitting foam box (six sided).  The temp rise for this experiment was much to slow to allow confidence in asingle hour of heat soak so I left it in the oven for 4 hours.  I originally wanted to do this particular phase of the experiment for 8 hours.  Unfortunately, if I stay close enuf to the kitchen to hear the oven timer I gain weight rapidly so I cut it to 4 hours.  75 degrees at the start and finished the four hour soak at 127 for a delta of 52 degrees for the four hours.  I divided the total delta by 4 to get the one hour heat gain of 13 degrees.  In this case, unlike sex, less is more.

With foam providing an inslation performsance(I made that up) of 13 degrees for.   two inches, you would need to have 112/8 coats to equal the erformance of te two inches of foam.  That is 14 thick coats...give or take.  I can cover 32 square feet with $35 worth of foam board.  I have never purchased the ceramic paint so maybe you can tell  me what 14 coats of an area or 32 sq feet would cost assuming you would need to cover 448 square feet. I applied the stuff with a 2 inch brush and it was thick as custard so I think that getting a uniform coat would require spray application with a lot of thinning or a texture coat gun if you don't thin it.  Your number will provide cost effectiveness info.

I cam honestly say that if I had to get "some"insulation performance from a 1/16 or 1/8 thick gap I would use the ceramic.

Were I you I would put foam board inside the glass.  I guess black would be as good as any color as the window will absorb most of the heat anyway and try to dump half of it inside.

This product is very light when dry.  It is soft enuf for me to press my thumb nail into it.  It would be unsuitable as an exterior coating for a roof due to its dirt pick up performance.  A high gloss white would be the best performer...So says UPS as they paint the roofs of their trucks white.  Thanks for the picture, who ever sent it so long ago.

If you are applying this paint inside a metal surface then color would not mean anything as  you are not reflecting anything.


Now, to get that nap outta the way,

John

[john9861]

John,
       Very good experiment. Since you have the necessary materials to conduct this type of experiment I was hoping to talk you into doing one more. I'm looking to find out if a certain thickness of polyiso board will be enough to satisfy protection from the outside temps. Since I have the polyiso board on hand at a fraction of the cost new I plan to use it instead of the blown foam. I have 1/2". I plan to use 2 layers. It would be great if we could find out 2 things. The temp of the metal after a certain soak. But this time take the reading at each hour. We might find that the rate of increase goes up faster in the latter sector of the experiment. Just curious. The other issue is to not have the steel inside the box, just air. Find the temp in this case as it would be somewhat representative of the inside air in the coach.  Or if you are limited in materials just use your 2" thick material with just air inside. this would be a great help in determining the usefulness of the polyiso board. Anyway, hope you're willing!
John

[JohnEd]

John,Thank you for your comments.  It will be a cold day in hell when something like this s posted and isn't picked at by many.  And in this case picked at with justification.

I used that big chunk of steel cause the bigger the item(more mass) the slower the reaction.  If I had lab equip(and somebody that had a clue) I could do the same experiment in minutes.

I don't think that what you are suggesting will be of much use to you.  I think it is a given that you can only get to a level of insulation performance that is "adequate or satisfactory" for you.  The rule is that you do it as well and to theextent that your wallet or sweat will support and then "there you are".  The proof is in the pudding and when you are done the clincher is how much one of those 1,500 watt heaters raises the temp.  I can get a 30 degree delta with all windows filmed, AC outlet stuffed full o FG and one person on board.  When the temp gets down to 44 F I have to bring another heater on line for the additional 30 degree delta and then I can tolerate temps down to 14 degrees.  I have 8 inches of foam in the roof and that is as good as that coach will ever get and it isn't that bad.  YMMV

You said you had lots of that 1 inch polyiso and that's great.  If it were free I would be sorely tempted.  Cut it a half inch under and glue it ti to wall.  Shoot small shots of the canned poly foam in the edges to prevent squeaking.  Ace looks to have cut his 1/ inch over and pressed the sheets in place.   I never heard him comment on squeaks going down the road.  That would tend to drive ya nuts tho.

Consider that you will want to get every cubic inch in the overhead filled with that foam board.  Might that not be 4 inches in most and 6 in other areas?  the little odd spaces need to be stuffed with FG or shot with foam. The floor needs at least a couple inches of foam board.  Some of that can be glued to the overhead of the compartment but I would opt for two layers of interlocking ply wood with an inch, at the very min, of foam in betweed.  Using two inches would use 320sq ft or 10 sheets per layer of 1 inch.  20 bottom, 30 roof, and 40 for the sides???  is that "lots" you have about 110 sheets?  You can check my math and compensate for the windows and such. At $35/sheet of 2 inch, the price here, and you need 55 sheets.... that's almost a couple grand and they will shoot it for around a grand and trim it and that "solid" construction will yield a much more quiet and better insulated bus.  I would use sheet for the floor and a single layer wherever it was open and convenient and spray over those places.  But if it is free and you have the time you can save a grand.   would spray all except the floor and the overhead in the bays and sell the rest to other converters.

Double pane glass and pastic frames that don't conduct heat are a must.  If the frame isn't at least isolated they will sweat badly in the winter

I will help you with whatever experiment you might find useful.

John

I hope these are some ideas you can ponder and it helps you with your final.   A big problem is air permeation while driving down the road.  Foam solves this problem very well but you cancertainly caulk and gasket everything to air tight.  A 1 sq inch hole can induct a LOT of warm/cold air with the pressure you get at the front at 60.

[ruthi]

Hi John. Well, you are getting a little too technical for me to follow,   but....... I see where your test didnt prove it to help that much. There needs to be a heat source on one side of the metal, so that it can reflect the heat outward. That is why they recommend using the ice cube test. Placing it in the oven, there is nowhere for the heat to be reflected to. It is suppose to be put on with a sprayer, and it is not to be diluted. We used an accousticle type sprayer. When I can put my hand on the roof metal,  in 100 degree heat, and get burned, and then put my hand where the ceramic was sprayed,and it is cool,  that is enough convincing for me. It really isnt anything to be compared to foam insulation. Two different uses. It has no insulation value, it is reflecting the heat. I dont know how you were able to press your fingernail into it, as we have it on the top of our bus, and you couldnt chisel it off it you wanted to. It may get dirty , but, we have a power washer for that, and a lot of other products will also get dirty. Hey, I can deal with getting a little dirty, if it means staying cool.   Anyhow, its all good John, take care and hope to see ya this year sometime. If anyone wants anymore info on the product we used, feel free to contact us.  Happy busin. Ruthi

[gus]

Does anyone know of a roof coating as good as this TC Ceramic that has a nice smooth surface?

Power washing the roof is way down on my list of fun things.