Exterior Painting

[Ed Gibbons]

I am painting trim that was in pretty bad shape. Lots of scraping, and power washing. House is located near ocean. Now its time to paint.

I know with paint its recommended to get the best. I am not sure if I should use an oil primer. Old school guys say yes but some research I have done points to latex. Latex is supposed to be much improved today.

Suggestions and advice appreciated. Thanks.
EG

[Dave Johnson29]

I will be watching closely Ed. I live at 6000ft and the UV from 330+ days per year of AZ sunshine is taking it's toll on my all-wood house. Yup, even the windows are wood.

Gonna have to paint before the end of the year.

Will you be using brush, roller or spray?

[Craig Summers]

Oil is good, but it takes longer to dry, and requires solvents to clean up after.

For a primer, you can go either way, you can put water (latex) over oil, but never oil over water. So if you plan on oil finish paint, you have to use oil primer.

[Mike Archambeau]

Do you know what wood species the trim is? If the paint has failed and the wood is still sound, it is probably cedar or redwood. Pine rots very quickly once exposed to water, making it very dificult to get a paint job to last. If the wood has any rot, it is best to replace the wood. This will ensure that the paint job lasts.

Providing that the underlying wood is sound, I would sand until the wood looks fresh. Weathered wood will not hold paint. Once you have sanded to fresh wood, I would prime with Benjamin Moore Exterior Wood Primer. The oil soaks into the wood, and helps preserve it. The Beni Moore primer dries in 4 hours. I would top coat with Beni Moore Aura exterior paint. Aura is a latex paint, but if flows like oil. It is a dream to work with. Probably the best latex paint ever produced.

Oil primer to feed the wood. Latex to protect the wood, since it remains flexible and won't crack as the temps change from morning lows to afternoon highs, or wood expands as humidity changes over the coars of the year.

[Prashun Patel]

Seems the choice of primer shld depend on what yr painting. I've heard people usually use latex outside bkz it breathes and flexes more than oil. However, if the wood is prone to staining, then a shellac-based primer might be appropriate.

I'm no pro. Just food for thought.

[Stephen Tashiro]

I wonder what paint is used on wooden benches and carriages of old cannons in the National Parks.

I notice that oil paint goes down into cracks in wood much better than latex paint , given that you take both straight from the can. I assume that is a point in favor of oils if the wood has some small cracks.

There are opaque (e.g. white) deck stains that appear to be oil based. Anyone know how they hold up?

The water sealant products that I have seen (like Thompsons) say to wait to paint over them with latex paints for 30 days. That seems like such a long time! Is thee something about them that makes the wait worthwhile? I think the opaque deck stains don't mention that long a wait if you want to paint over them.

[Mike Archambeau]

Seems the choice of primer shld depend on what yr painting. I've heard people usually use latex outside bkz it breathes and flexes more than oil. However, if the wood is prone to staining, then a shellac-based primer might be appropriate.

I'm no pro. Just food for thought.

Oil based primers dont build thickness, so they are not prone to cracking. Top coats build mils of thickness, so remaining flexible is very important, thus the advice of flexible latex top coats. In the USA you can still buy a gallon of primer, because it is the ONLY product that can block the tanins in the wood from bleeding through the top coat. But due to the VOC laws, you can only buy oil based top coats in a one quart can. So the regs steer you to latex top coats. The paint manufacturers have responded by creating phenomenal latex top coats like Aura from Beni Moore.

I have a house with wood trim, and wood clapboard siding. My trim has oil based primer and latex top coat. My wood shutters are done the same way. The cedar claps have Beni Moore solid color stain. It is performing very well. I know this because I have painted every inch of the place over the past 7 years. Good wood (cedar or red wood if you can still get it) and good paint or solid stain is a good combination. Some of my trim was pine, and if you are not there the day the paint fails....sadly the wood fails. Every piece of failed pine trim has been replaced with cedar and the paint schedule I articulated earlier.

[Phil Maddox]

Sherwin Williams - Duration - best exterior out there IMO. Been using it professionally for 12 years - not one problem.

good luck

Phil

[David G Baker]

Ed,
I had a problem with my trim on the West side of a home I owned in California. I painted it a couple of times with the best paint that I could find, spent a lot of time preparing the surface but the paint would only last around 3 years before it would start having problems. I got angry and covered every piece of wood with aluminum coil that is used when vinyl siding is installed. That was at least 15 years ago. The last time I saw the house the trim was still looking great. The coil was not much more than the two paint jobs cost me.
I have used exterior latex paint on wood that had not been painted before that I prepped the wood according to the instructions that came with the paint that has held up very well. My problem in California was the wood had been painted before and I could not get the wood down to bare wood without doing a lot more work than I wanted to do. The original paint may have been lead paint that was 40 years old.

[Neal Clayton]

I wonder what paint is used on wooden benches and carriages of old cannons in the National Parks.

I notice that oil paint goes down into cracks in wood much better than latex paint , given that you take both straight from the can. I assume that is a point in favor of oils if the wood has some small cracks.

There are opaque (e.g. white) deck stains that appear to be oil based. Anyone know how they hold up?

The water sealant products that I have seen (like Thompsons) say to wait to paint over them with latex paints for 30 days. That seems like such a long time! Is thee something about them that makes the wait worthwhile? I think the opaque deck stains don't mention that long a wait if you want to paint over them.

that old paint in the national parks is probably the original linseed oil/lead paint. it was put on without a primer, and designed to penetrate. there are a few reasons it lasts so long, but primarily because the lead doesn't deteriorate any time soon, and it takes a good long while for the wood to lose all of the linseed oil it can soak up. whereas with modern oil paints, it only has to lose the bit of oil between the primer and the outside of the paint film itself. plus, since the binder was also the solvent, you could 'freshen up' lead paint by just brushing a new coat of linseed oil on it, thus stopping any pigment loss and giving it another few years of life.

if white is all you need, you can still get milk paint that works the same way (no primer, some of it penetrates into the wood) from a few places, but the caveat is only in white, because milk paint will spot outside in the rain, you just can't see the spots on white. this would be similar to the 'whitewash' that people used to use on fences. milk paint allows the wood to breathe, so it'll take on a little moisture, but there's some sort of property of the lime that makes the paint get tougher and grab harder as that little bit of moisture passes through and then dries back out again, so milk paint will last a good while outdoors in the weather (15+ years before you absolutely need another recoat).

deck stains will have a shorter maintenance cycle than paint, but in the long term, not a bad idea for outdoor furniture and decks, imo. while the paint might last 10-12 years, you'll get 5-7 out of the stain (depending on sunlight exposure and how dark the stain is, darker lasts longer), but the stain can just be recoated without any sort of prep, and you don't have to worry about building up too much film on it, like you would with paint.

there's actually a company that's making linseed oil paint similar to the old lead formulas, only with iron pigments and titanium white in lieu of the lead, allback paint company, based in sweden, they have a couple of importers in new york, you can order it on the net. if you search for allback paints you should turn up a few online stores.

from my experimenting with it, i like it, it leaves a sheen and film similar to the old lead paints, and penetrates quite well, so it's worth a try if that's the look you want

if you use a modern paint, yes you should always use an oil primer on outdoor surfaces. oil penetrates as it does that slow drying. the better the primer bond, the longer the paint will last. i would wager the longevity difference between a slow oil primer and a latex primer from my experience with windows and doors to be about 5 years. i've seen oil primed windows that were done 12-13 years ago that look fine, and latex primed ones that fail in 7, with the same type of paint on top.

out of the two options for modern paints, i'd say that acrylics are the better option, since they fail more gracefully than modern oil paints do, the only reason modern oil paint formulas still have a consideration is for windows and doors, since the abrasive resistance is better than acrylic enamels (at least they were the last time i tried an acrylic enamel). short of that, acrylic is now the way to go, with modern paints.

my excuse for typing all this despite not working for a paint company: buy an old house, wind up writing a paint dissertation based on raw trial and error (more than once!) ;)

[Dave Ogren]

If you are going to use latex, I think that the Behr line is the best, and has never let me down. Some of the older proffessional painters say "If it ain't toxic, it ain't very good." Just more to think about.
Good luck,

Dave

[Stephen Tashiro]

if white is all you need, you can still get milk paint that works the same way

I enjoyed reading all your answers, Neal. I do have use for a white paint for my white fence, which I must soon rebuild. Where would I find "milk paint"?

[Neal Clayton]

milkpaint.com

realmilkpaint.com

realmilkpaint sells a borate additive as well, which i would use in the mix. reason being, any natural product (milk paint obviously being one) can be food for mold/mildew. they eliminated this problem in the old days with boric acid, they treated everything from wood to leather to food stored over the winter with it. it's quite deadly to insects and fungus, but fairly harmless to people. that practice existed on exterior wood until commercial paint suppliers became widespread, when everyone used their own 'mix' for paint borate treatment was commonplace (which is one of the primary reasons why old wood structures are still around, despite neglect).

here's an LSU study on the longevity and fungus resistance of wood, with/without borates...

http://docs.google.com/gview?a=v&q=cache:RHXLIipLyzkJ:www.rnr.lsu.edu/wu/PDFFiles/Decay%2520and%2520mold%2520Paper%2520IRG34.pdf+cyp ress+mold+resistance&hl=en&gl=us

also note that it has a very short shelf life once mixed. mix enough to use and use it the same day, after a week or so it'll start to turn bad.

alot of things the old timers did was better than what we have today, and i honestly believe that paint is one of those.

for traditional windows, the reintroduction of linseed oil based formulas is especially nice, since with modern products (typically dap33 and alkyd enamels) you have to wait a week or two depending on the weather for glazing putty to skin over before you can paint it. with linseed oil putty and linseed oil paint, like they used in the old days, you can putty and paint in the same day and the two bond to each other whether one or the other is cured or not.

now, if only i had an under the table source for lead white, i'd be in business ;)