# painting over new aluminum siding



## mastr (Apr 15, 2011)

Hey guys, quick question for you.

I have a exterior job where I have to paint a semi-gloss over new aluminum siding.

Should I prime the surface?

In the past I have painted flat paint (no primer) over this type of surface without any problems. Does this change now that I am using gloss?

Thanks!!:thumbsup:


----------



## propainterJ (Jan 31, 2011)

You must abrade,get a good angle grinder on it conform to SSCPA-2 UPI standards and you should be fine!


----------



## cdaniels (Oct 20, 2012)

I would use an oil based primer.


----------



## premierpainter (Apr 17, 2007)

Latex will be fine.


----------



## Paradigmzz (May 5, 2010)

what kind of metal surface? is it prefinished? if so and it has kynar in the finish then you need dtm or adhesion coat. (kynar is used in prefinished baked on coatings) . if it is brand spanking new, you need to get the mill glaze off or it will peel in sheets, especially since it is a higher sheen. diluted vinegar and some elbow grease or pressure wash. Tou could use a Wash Primer as well. If it is a huge area, i would suggest going with a more robust system like DTM or SW Bond Plex. Bond Plex will even coat galvanized without a Wash Primer. If the panels are galvanized, you definitly need to get the mill glaze off and then . use a wash primer and then topcoat in DTM or use Bond Plex.

Edit- you said aluminum siding. i was thinking metal building paneling. I dont have a clue about aluminum siding on houses. Im from the land of Hardi and brick.


----------



## 1camper (Feb 17, 2013)

Scotchbrite and self etching primer.


----------



## NCPaint1 (Aug 6, 2009)

1camper said:


> Scotchbrite and self etching primer.


Overkill. Make sure there is no chalk. Wash and scrub if necessary with TSP. Typically you don't need to prime, but that depends on what product you are using. BM Regal or Aura lines would not require priming.

Clean and free of chalk is most important.


----------



## Stonehampaintdept (Jan 10, 2013)

I'd suggest a DTM or Grip coat type bonding primer. 
Sidenote- California is going to be launching a 100% acrylic DTM in the near future, Novus. Consumer friendly labeling, technology derived from their Industrials. Contractor night testing got very good feedback.


----------



## Delta Painting (Apr 27, 2010)

NCPaint1 said:


> Overkill. Make sure there is no chalk. Wash and scrub if necessary with TSP. Typically you don't need to prime, but that depends on what product you are using. BM Regal or Aura lines would not require priming.
> 
> Clean and free of chalk is most important.


^^^This^^^:thumbsup:


----------



## Rbriggs82 (Jul 9, 2012)

If it were my job I'd add emulsa bond to the paint on the first coat for good measure.


----------



## NCPaint1 (Aug 6, 2009)

Rbriggs82 said:


> If it were my job I'd add emulsa bond to the paint on the first coat for good measure.


I have a love/hate with EB. Like most additives, they can do more harm than good if not done properly. Yeah you could mix some on the first coat if you wanted though.


----------



## Rbriggs82 (Jul 9, 2012)

NCPaint1 said:


> I have a love/hate with EB. Like most additives, they can do more harm than good if not done properly. Yeah you could mix some on the first coat if you wanted though.


We've done 100's of aluminum houses that were chalky as hell even after pressure washing. Our system was always moorgard with EB in the first coat then top coat without. They looked great an held up until the paint faded. After the first coat you couldn't scratch it off. 

Now I'm not sure how EB works with the gennex paints but it was awesome in moorgard.


----------



## Gough (Nov 24, 2010)

It's the "new aluminum siding" part that gives me pause, for those same reasons that Para has mentioned. Since it's new, chalking probably won't be the issue. 

A quick GIS came up with a Glidden technical paper about it:

http://www.gliddenprofessional.com/...GP_AP9_Painting_Aluminum_and_Vinyl_Siding.pdf


----------



## Rbriggs82 (Jul 9, 2012)

Gough said:


> It's the "new aluminum siding" part that gives me pause, for those same reasons that Para has mentioned. Since it's new, chalking probably won't be the issue.
> 
> A quick GIS came up with a Glidden technical paper about it:
> 
> http://www.gliddenprofessional.com/pdfs/techBulletins/applications/GP_AP9_Painting_Aluminum_and_Vinyl_Siding.pdf


I missed that it was new aluminum. I've only painted the old chalky stuff so disregard my previous advise.


----------



## TJ Paint (Jun 18, 2009)

Gough said:


> It's the "new aluminum siding" part that gives me pause, for those same reasons that Para has mentioned. Since it's new, chalking probably won't be the issue.
> 
> A quick GIS came up with a Glidden technical paper about it:
> 
> http://www.gliddenprofessional.com/...GP_AP9_Painting_Aluminum_and_Vinyl_Siding.pdf



I love technical bulletins. It's what I used to seek out and I read every one I could find. This was before the internet took off. 

Now it's pretty easy to find all this stuff out if you take a bit of time.


----------



## 1camper (Feb 17, 2013)

NCPaint1 said:


> Overkill. Make sure there is no chalk. Wash and scrub if necessary with TSP. Typically you don't need to prime, but that depends on what product you are using. BM Regal or Aura lines would not require priming.
> 
> Clean and free of chalk is most important.


OP said "new".. so no chaulking and no need to wash. I assume he is spraying so putting down a coat of self etch is too easy and ensures adhesion no matter the topcoat. Also, if there is oil or residue from people's hands who installed the aluminum you can identify it in the self etch and not find out about it in the topcoat.


----------



## mastr (Apr 15, 2011)

Thanks, a lot of good advice in this thread!


----------



## NCPaint1 (Aug 6, 2009)

1camper said:


> OP said "new".. so no chaulking and no need to wash. I assume he is spraying so putting down a coat of self etch is too easy and ensures adhesion no matter the topcoat. Also, if there is oil or residue from people's hands who installed the aluminum you can identify it in the self etch and not find out about it in the topcoat.


Are you kidding? Wash no matter what. I would never...ever, paint any exterior without washing. New or not it gets washed. Washing will remove oils too. If an exterior sits over 2 weeks between wash and paint, guess what? It needs to be rewashed.

Self etching primer? Its not a car bud. That is also completely unnecessary. How many homes have you painted? How many rattle cans of "self etching" primer does it take to paint the average exterior?

Also, you don't need to sand aluminum like the other guy said. You do not sand aluminum siding. A green scotch pad if you have some stubborn bird poo is fine. A pole brush and TSP is more than sufficient. 

EB is also fine to use on the first coat. It's not a product I rely on, but if you like it and are more comfortable with using it, go for it.


----------



## 1camper (Feb 17, 2013)

What's crazy is painting a shiny surface like you suggest is OK. More and more I see factory painted aluminum trim peeling and revealing a shiny metal surface underneath...it wasn't sanded or self etched. ..it was clean tho..
A red scothbrite will clean new siding enough to paint it...put it on a sanding pole run over the siding lightly. Rattle cans?? No. If your paint store doesnt sell it, go to any Napa and get self etch in a quart, activator, reducer ...it'll make almost a gallon and go a long, long way. All you need is a tack coat. 
Doesn't matter what the metal is covering, house, car, airplane...it's metal and never needs to be washed with tsp to paint.


----------



## NCPaint1 (Aug 6, 2009)

1camper. I'm not poo pooing your suggestions. I've never seen BARE aluminum siding installed on a home before. It has a factory finish on it. Maybe in your area they install unfinished aluminum siding, but here its always factory finished.

People will typically paint it because its either old and crappy looking, or they simply don't like the color.


----------



## 1camper (Feb 17, 2013)

Not bare, new..powdercoated. some of the newer painted aluminum "wrap" is not properly painted. When exposed to direct sun for extended periods it peels... Also, where it is bent it'll start to peel.

I understand it's new painted aluminum. If it's shiny it should be scratched and you should use an adhesion promoter. You could use a deglosser, which is what you are suggesting with tsp, but imho, red scotchbrite and self etch would be faster and more effective than washing and hoping.


----------



## 1camper (Feb 17, 2013)

Let me try explaining this a different way...

Let's say it's a metal exterior door with paint in good condition. Washing it with tsp wouldn't be all you would do to prep it, would it? You would suggest scratching it up some, right? Why is it different for siding?


----------



## NCPaint1 (Aug 6, 2009)

1camper said:


> Let me try explaining this a different way...
> 
> Let's say it's a metal exterior door with paint in good condition. Washing it with tsp wouldn't be all you would do to prep it, would it? You would suggest scratching it up some, right? Why is it different for siding?


Completely different. If its high gloss then yes, satin no. Clean and paint. Finish coat product can change the prep though.


----------



## 1camper (Feb 17, 2013)

I didnt say high gloss...you're assumption. I said paint in good condition. No sanding or scratching? You'd be crazy..


----------



## Bender (Aug 10, 2008)

NCPaint1 said:


> Are you kidding? Wash no matter what. I would never...ever, paint any exterior without washing. New or not it gets washed. Washing will remove oils too. If an exterior sits over 2 weeks between wash and paint, guess what? It needs to be rewashed.


Especially behind the ears.


----------

