Exterior Paint: Everything You Could Possibly Need To Know

Exterior paint provides a protective shell around your home. Without it, your home is a sitting duck against anything the weather decides to throw at it — except it's not as weather-resistant as a duck. Weather is a formidable adversary that has no trouble wearing down even the best exterior house finish in a short time. Typically, the best exterior house paints can provide adequate protection for only about 10 years. Most homes — whether stucco or wood siding — need repainting every seven years on average.

Exterior house paint needs to be tough to combat the sun, rain, and harsh weather. The paint also needs to be attractive. For many years, oil-based exterior paint was the go-to solution for durability and good looks. Water-based paint, however, especially acrylic, has largely taken over the market due to regulations placed on volatile organic compounds (VOCs) that are prominent in oil-based paints. But oil-based paints still have a place in the world of exterior paint.

Exterior paint consists of various combinations of four main ingredients:

1. The vehicle or carrier: This is the liquid in which the other ingredients are bound. The vehicle in water-based paint is water; the vehicle in oil-based paint is oil or a chemical solvent.
2. The pigment: This can be a single ingredient or several combined ingredients that give the paint its color. Modern pigments are typically synthetic chemical compounds that are more durable than natural ingredients.
3. The binder: This is the ingredient that holds all of the ingredients together and adheres the paint to the wall. Binders give the paint qualities such as sheen, durability, and other characteristics. Oil-based paints use alkyds and various oils as binders. Water-based paint, also referred to as latex paint, uses various acrylics combined with other chemicals as its binder. Water-based paint with a 100 percent acrylic binder is called acrylic paint, while latex paint uses binders other than or in addition to acrylic.
4. The additive: This can can include mixes of several chemicals and compounds. Additives give the paint extra characteristics, such as flow, thickness, shelf life, mildew resistance, and other qualities.

There are two main types of exterior paint: oil-based and water-based. Water-based paints are further divided into acrylic paint and latex paint. Both oil- and water-based paints have several pros and cons to consider.

Second only to choosing your exterior paint color, you'll need to select its finish or sheen. The finish refers to how shiny the paint appears after drying. Additionally, a paint's finish can affect its durability and water resistance. There are several types of exterior paint finishes, including the following:

Gloss

Gloss exterior paint is shiny, smooth, and typically reserved for use on trim work and architectural details to give them a rich color that stands out and draws attention. Gloss paint is remarkably tough and provides a durable finish thanks to its strong binder compounds that also make it very water-resistant.

The same attributes that make it an excellent trim paint, though, are the same ones that make it a poor choice for the rest of the exterior. The hardness of the paint means it becomes brittle in extreme temperature fluctuations. Water-resistant paint keeps damaging water out but can also trap it within the walls of the house. Also, although the paint is beautiful, it doesn't hide flaws in the siding and can even highlight them.

Semigloss paint is a step down from gloss in terms of shine. Almost as durable as gloss paint, semigloss paints have a binder that produces a tough and water-resistant finish, but it isn't as reflective as gloss paint. This reduced glossiness make semigloss somewhat better at hiding imperfections in window and door trim, making it a popular choice for trim work on older homes.

Satin-finish paints are another excellent choice for trim. Satin paint's binders create a limited but noticeable shine balanced with semitough durability and water and mildew resistance. Satin paint also works well on larger trim areas, such as soffits, doors, porches, and railings, where it may encounter frequent touching.

Eggshell paint finish lands between satin and flat paint and is great for use on both trim work and as a primary house body paint. Eggshell paint isn't glossy, but it isn't dull either. It can hide some slight imperfections in siding and trim. It also offers some resistance to water and mildew. In general, eggshell paint is a solid all-around exterior paint finish.

Flat paint has a matte finish and can appear rough to the touch. Flat paint has little water resistance, and its porous nature can harbor mold and mildew. However, flat paint's duller finish can hide imperfections better than any other paint, making it the go-to choice for covering older houses. Also, flat paint's porosity is necessary for painting masonry structures that need to breathe.

To know how much exterior paint your home needs and to estimate the painting cost, you'll need to do some math. Here are the steps necessary to accurately determine how much you'll need.

How to Estimate Primary Paint Quantity

1. Measure the home's perimeter and multiply it by the average exterior wall height.
2. For each gable end, measure the bottom width of the gable end and multiply the number by its height. Divide the answer by two.
3. Add all of the sums together for a total surface area in square feet.
4. Count the number of windows and doors.
5. Subtract the average square-foot amounts for each window and door.
6. Factor in enough paint for two coats if necessary.
7. Divide the total by the paint's listed coverage area per can.

1. Measure the length of trim work around an average window and a door. Multiply the total by the number of doors and windows.
2. Multiply the sum by the average width of the trim.
3. If you're painting the soffits and/or fascia trim, multiply the length and width of each section or piece.
4. Add all the totals and divide the answer by the listed coverage area on the paint product.

Painting a house exterior is hard work and costs real money, but a good paint job lasts for a long time. Here are tips to make your exterior paint project go the distance.

• Wash your home's exterior with a pressure washer or by hand with a mild soap solution.
• Scrape away any remaining loose paint.
• Fill holes, cracks, and knots in the siding with wood putty or patching compound.
• Sand down any rough spots in the siding and where you made patches.
• Apply the right primer and paint. Use oil-based primer over oil paint and oil or latex primer over water-based paint.
• Caulk and seal joints around windows and doors with a high-quality exterior-grade siding caulk.
• Perform your paint job during good weather.

A fresh paint job needs time to fully cure to provide the best protection. Proper curing requires ideal temperatures and humidity levels. The best time to paint your house is when the temperature is between 40 and 90 degrees Fahrenheit for oil paints and 50 to 85 degrees for latex or acrylic paints. The humidity level should be between 40 and 70 percent with no chance for rain in the following few days. Overcast skies are better than direct sunshine.

Painting your home's exterior is a big job. An average-size house could take up the better part of a week to accomplish on your own. However, you'll save significant money doing it yourself instead of hiring a painting company due to labor costs and profit margins. How much you'll save greatly depends on the labor market and your regional location. The average cost for a professional paint job is between $3,000 and $8,000 for a 2,000-square-foot house.

To determine if it's worth your time to paint your home's exterior, obtain a couple professional estimates and compare them to the cost of materials at your local home center. Remember to factor in the cost of painting tools that you may not already own.

The best exterior paint for your home depends on several factors, including durability, color depth and shine, application ease, and the material you're covering. Choose from one of these types.

• ​Water-based acrylic paint,​ or acrylic-latex, is an excellent all-around paint that combines durability and a long life span with resistance to fading, mildew, and UV rays. Use trusted acrylic paints for body and trim work applications on any siding material.
• ​Oil-based paint​ provides long-lasting durability that holds up to extreme weather changes. Oil paints cover thoroughly, hide brush strokes, and provide high-gloss sheens and deep colors. Use high-quality oil-based enamel paint on trim work to show it off.