Interior paint on Exterior - Contractor Talk - Professional Construction and Remodeling Forum

jjocsak · 10-15-2009, 10:01 AM

I accidentally painted a couple of porch posts with interior semi-gloss paint before I realized it.

What are my best options to correct this?

Thanks
Jeff

Darwin · 10-15-2009, 10:03 AM

strip it raw and start again! he he.

jjocsak · 10-15-2009, 02:09 PM

What would be the harm of giving it a topcoat of exterior?

Jeff

Metro M & L · 10-15-2009, 08:32 PM

I don't know. Put it on there and plan on getting a call next year to find out what happened!

jjocsak · 10-15-2009, 09:04 PM

Actually it's my own house, go figure.

Jeff

Faron79 · 10-15-2009, 10:07 PM

Seriously...there's little worry here!

Technically, typical Interior resins are a little harder. Exterior binder-resins are usually slightly more "flexible".
It'll probably wear just fine. Slight odds of it cracking earlier, depending on the wood' movement.

Faron

jjocsak · 10-15-2009, 10:38 PM

Quote:

Originally Posted by Faron79

Seriously...there's little worry here!

Technically, typical Interior resins are a little harder. Exterior binder-resins are usually slightly more "flexible".
It'll probably wear just fine. Slight odds of it cracking earlier, depending on the wood' movement.

Faron

Thanks, I was thinking the same thing but wasn't quite sure.

Jeff

NAV · 10-16-2009, 07:45 AM

I have been told by Paint Reps that if you apply interior coatings on an exterior they will fail.

If you coat over them with an exterior product they will still fail. what will happen first is the exterior top coat will become chalky within a year and then you will have the peeling and blistering.

I have not tried it to see if my Rep is correct but if it is your house I say let it go and see what happens.

jjocsak · 10-16-2009, 07:59 AM

Thanks NAV.

I was an interior semi gloss enamel if that matters.

I guess it's time for an experiment.

Jeff

4thGeneration · 10-16-2009, 09:31 PM

Exterior and Interior paints are manufactured to hold up to the elements they are meant to be applied in. An interior paint used as a first coat on an exterior application with an exterior paint applied over that is just trouble. It will not last and you will have bubbling paint because the interior coating will not hold up. Even with a top coat of exterior on it.

I know sometimes like SW can get confusing when using Super Paint because they make both Interior and Exterior for the same name. Thats why i always check, check and recheck all the labels. We actually had new people at the paint stores shoot an exterior color for an interior paint and vica versa.

jjocsak · 10-17-2009, 04:18 PM

This is what the manufacturer said:

You may apply an exterior paint over the existing interior paint. This will seal the coating and prevent any future problems.

Jeff

4thGeneration · 10-17-2009, 05:01 PM

Quote:

Originally Posted by jjocsak

This is what the manufacturer said:

You may apply an exterior paint over the existing interior paint. This will seal the coating and prevent any future problems.

Jeff

Not meant to burn you, but in my opinion that Rep may be mixing his meds...

jjocsak · 10-17-2009, 07:05 PM

Quote:

Originally Posted by 4thGeneration

Not meant to burn you, but in my opinion that Rep may be mixing his meds...

I think you may be right....

Jeff

Frankawitz · 10-18-2009, 05:17 AM

The paint will peel

strip and repaint

Wolfgang · 10-18-2009, 06:19 AM

First thing is to turn in your Painters Card.... just kidding. 6 years ago I had a guy do the same thing to his porch columns, we went over it with oil-based CoverStain primer and topcoated it with exterior. Other than the regular exterior grime they've held up through the Nebraska weather extremes. Might want to give it a shot.

jjocsak · 10-18-2009, 06:34 AM

Quote:

Originally Posted by Wolfgang

First thing is to turn in your Painters Card.... just kidding. 6 years ago I had a guy do the same thing to his porch columns, we went over it with oil-based CoverStain primer and topcoated it with exterior. Other than the regular exterior grime they've held up through the Nebraska weather extremes. Might want to give it a shot.

Wolfgang, very interesting.

Do you think it was the oil based that was the key or just the primer/topcoat application by itself?

I'm also curious if the interior coat was also oil?

Jeff

vandyandsons · 10-19-2009, 06:08 PM

I think you should be ok if you prime it with an oil primer and topcoat with an high quality exterior paint.

give it a try and let us know in the spring!

Dave R · 10-19-2009, 06:29 PM

Last year I was working on a job where the painters painted the exterior of the house we were renovating with interior paint. They couldn't speak or understand English so they didn't understand when we tried to tell them. The GC didn't make them redo it so the interior paint stayed on. I went by the house a couple weeks ago and the paint still looks good.

Framer53 · 10-19-2009, 06:33 PM

Quote:

Originally Posted by jjocsak

Thanks NAV.

I was an interior semi gloss enamel if that matters.

I guess it's time for an experiment.

Jeff

Don't worry, been there done that 8 years ago. Just scraped and repainted this year!!

Jeffrey Watson · 10-25-2009, 10:42 PM

I would not do anything. It might hold up depending on wheather conditions. Wait and see, if it holds up Great! If not fix it after it fails. I mean you got better things to do Right