Latex or oil-based enamel? which is the best for exterior house painting
When it comes time to paint the exterior of your house, you will be faced with making the choice between water-based latex paint and oil-based enamel. Oil-based paints have been around a lot longer than the latex paints. Many older homeowners and professional painters are naturally biased toward them for this reason. When latex paints were first introduced, many were clearly inferior and the paint would soon start peeling. This led to all sorts of misinformation. Many people think you can't put latex paint over old surfaces painted with oil-based paint, or vice-versa, that you can never paint with oil over a coat of latex. None of this is true. Latex paints have been vastly improved, and now all paint manufacturers offer a line of latex paint. It is, in fact becoming more common to use latex paint for exterior painting than oil-based paints. We'll examine some of the differences and look at the advantages and disadvantages of each here:
Oil-based enamel paint is usually more expensive than latex paints, except for some of the modern, so-called water-borne coatings that are in reality just another variety of latex paint. Aside from the cost, many homeowners don't like the idea of using oil-based paints because of the perceived difficulty of applying them. Oil-based paints are not affected by water, so thinning and clean-up of brushes, hands, etc., must be done with a solvent such as mineral spirits or paint thinner. More care must be taken with paint brushes when cleaning them, and oil-based paint is slow drying, so if you spill it on your ladder or other surfaces it can still get smeared around for hours.
Water-based latex paint is usually several dollars per gallon cheaper, and is easily cleaned up with just water. You can thin it, if necessary, with plain water, and you can wash your brushes and hands under an outdoor faucet or even in the kitchen sink. It dries quickly, so it doesn't make a big mess if you're a sloppy painter. On the other hand, this quick-drying characteristic makes it necessary to clean up any spills a lot sooner before the paint dries. The good news is that spills too can be cleaned up with plain water.
A disadvantage of this quick-drying latex is that it also tends to dry even as you spread it on a hot day. It's harder to get a smooth finish with latex, and after an hour or so of work, it starts to dry within the bristles of your paintbrush and can ruin a paint brush if you don't wash it out frequently throughout the day. Oil-based paint goes on much smoother and levels itself out during its long drying time, thus it is much better for places where a fine finish is desired such as doors and other large, flat surfaces. When both types of paint are dry, you will likely see more evidence of brush marks in a latex paint job as opposed to oil-based.
If rain is expected when you are ready to paint the exterior of your house, it can ruin your day if you are using latex paint. Since this paint is water-soluble, rain will wash it right off if it's not dry. Oil-based paint is more forgiving of rain and humid conditions, allowing you to work on more questionable days.
Another important difference between oil-based enamel and latex paint is the level of gloss in the final, finished paint job. Most latex paints are flat or semi-gloss in their finish, although some newer water-based paints are almost as glossy as oil. Nothing quite matches high-gloss oil-based paint for a shine however, so if this is the kind of finish you want, oil-base is the way to go. This brings us to the final point of comparison - durability.
Those who like each type of paint swear by the durability of their favorite. In general, since oil-based paints are glossier, they reflect more light and therefore in situations where they are exposed to full sun, should last longer than flatter, latex paints. Oil based paint is also good for houses surrounded by a lot of greenery and trees, as it seems to be more mildew resistant. That said, it seems that of all the houses I've painted over the years for paying customers, the houses painted with oil-based paint have to be repainted more frequently. After a few years, they begin to flake and peel, whereas many houses painted with latex still look acceptable after 10 years.
The truth is, either type of paint will protect your house. You have to weigh the differences and consider the difficulties of working with each when making a decision.
Oil-based enamel paint is usually more expensive than latex paints, except for some of the modern, so-called water-borne coatings that are in reality just another variety of latex paint. Aside from the cost, many homeowners don't like the idea of using oil-based paints because of the perceived difficulty of applying them. Oil-based paints are not affected by water, so thinning and clean-up of brushes, hands, etc., must be done with a solvent such as mineral spirits or paint thinner. More care must be taken with paint brushes when cleaning them, and oil-based paint is slow drying, so if you spill it on your ladder or other surfaces it can still get smeared around for hours.
Water-based latex paint is usually several dollars per gallon cheaper, and is easily cleaned up with just water. You can thin it, if necessary, with plain water, and you can wash your brushes and hands under an outdoor faucet or even in the kitchen sink. It dries quickly, so it doesn't make a big mess if you're a sloppy painter. On the other hand, this quick-drying characteristic makes it necessary to clean up any spills a lot sooner before the paint dries. The good news is that spills too can be cleaned up with plain water.
A disadvantage of this quick-drying latex is that it also tends to dry even as you spread it on a hot day. It's harder to get a smooth finish with latex, and after an hour or so of work, it starts to dry within the bristles of your paintbrush and can ruin a paint brush if you don't wash it out frequently throughout the day. Oil-based paint goes on much smoother and levels itself out during its long drying time, thus it is much better for places where a fine finish is desired such as doors and other large, flat surfaces. When both types of paint are dry, you will likely see more evidence of brush marks in a latex paint job as opposed to oil-based.
If rain is expected when you are ready to paint the exterior of your house, it can ruin your day if you are using latex paint. Since this paint is water-soluble, rain will wash it right off if it's not dry. Oil-based paint is more forgiving of rain and humid conditions, allowing you to work on more questionable days.
Another important difference between oil-based enamel and latex paint is the level of gloss in the final, finished paint job. Most latex paints are flat or semi-gloss in their finish, although some newer water-based paints are almost as glossy as oil. Nothing quite matches high-gloss oil-based paint for a shine however, so if this is the kind of finish you want, oil-base is the way to go. This brings us to the final point of comparison - durability.
Those who like each type of paint swear by the durability of their favorite. In general, since oil-based paints are glossier, they reflect more light and therefore in situations where they are exposed to full sun, should last longer than flatter, latex paints. Oil based paint is also good for houses surrounded by a lot of greenery and trees, as it seems to be more mildew resistant. That said, it seems that of all the houses I've painted over the years for paying customers, the houses painted with oil-based paint have to be repainted more frequently. After a few years, they begin to flake and peel, whereas many houses painted with latex still look acceptable after 10 years.
The truth is, either type of paint will protect your house. You have to weigh the differences and consider the difficulties of working with each when making a decision.
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