Exterior clear coat material querry

[bahed]

I have made some exterior signs that will be outside & used a quality primer and paint on them. I was hoping to get a recommendation for a readily available product to clear coat protect the paint for quite some time. I live in a town where there is a Home Depot, Lowe's, Sherwin Williams, Diamond Vogel, Benjamin Moore and a PPG paint.

The Sherwin Williams associate didn't give me a lot of confidence, and at the PPG store they recommended Defthane Dft25.

Any advice would be greatly appreciated.

Bret

[cowboy1296]

I dont have a lot of experience but a lot of people recommend sikkens log and siding

[joe]

In order to recommend a top coat it's necessary to know what you've done so far. What kind of substrate and paint have you been using? Cedar, redwood, mdo, hdu, dibond, aluminum or what?

[bahed]

It's expanded PVC substrate that I applied Sherwin Williams paint over. First I applied their best primer followed by exterior Duration. This was applied before I cut the letters/numbers/design, so there is some exposed PVC as well as the paint that I need to cover. The sign will be outside. Thanks for those questions so that I could better clarify.

Bret

[joe]

Are you sure you need to topcoat the SW paint? I seldom so! When using exterior grade PVC it's not necessary to prime. We apply DTM which has never failed hold up.

[bahed]

I just assumed it would hold up better outside with a clear coat over top of the paint. A couple of questions:
1. Is that 'DTM' an exterior acrylic , opaque, paint product from Sherwin Williams ?
2. Are you saying that the expanded foam product is fine without any kind of product over it in the elements ?

I'm ok with the exterior Duration that covers a majority of the sign, so if I don't have to do anything else to it, I'd be REALLY glad to go ahead and just mount it now and not wait for another couple of more days for cure time of another product!!
Thanks,
Bret

[joe]

Bret,

There's no advantage to top coating the premium acrylic latex paints. Check with your SW dealer. Houses don't get clear coats.

HD PVC is good to go as it is. No need for primers. It should be scuffed before painting.

[kevin]

For whats it worth I learn the hard way you get no extra protection with clear coat the opposite your trapping all moist ,The wood or substrate needs to breath .Look at old siding with oil paint how it peels off that's because moist is trapped and can't escape .
I used Modern Masters followed there directions {not mine} with clear coat peeled off .Remember I have sideways rain with salt at 50 miles and hr .What we think is stronger or last longer its sometimes not the case

[joe]

Thanks Kevin for backing me up. Nothing better than a first hand example. I know you have some of the most challenging weather and it's good to see how you deal with it.

Joe

[lentzie]

Hi. This is my first post on the forum. I would like to thank everyone for all the great information. For the last year I have been doing my homework and learning all I can from this forum and others. Through good fortune I have connected with a real estate company that manages apartment complexes across the state. They need several large entrance signs updated to include ADA and equal housing symbols. I currently have three 42” x 72” signs in process. I am using 1 ½” precision board HDU. Based on recommendations from members I am using Nova acrylic paint. I have been roller applying two coats of paint and two coats of Nova’s exterior varnish #216. I was assuming the varnish would give extra protection and I like the semi crinkle surface I get from using a short knap roller. Should I stop using the varnish? Thanks!
Dave