House Exterior Painting – Frequently Asked Questions

House exterior painting is not only practical but also an important step in home maintenance. But how do you ensure the painting is done perfectly?

In this article, we address the most frequently asked questions about exterior painting – whether it’s about timing, weather conditions, or choosing the right paint. When is the best time to pick up a brush? Can you paint in winter? And what happens if you paint in weather that’s too cold or too humid? We’ll cover all the important aspects so you know how to prepare and achieve the best possible result – whether your goal is to protect your house from the elements or simply give your home a fresh new look.

Why is house exterior painting important?

House exterior painting is important because paint protects the building from weather effects such as rain and the sun’s UV rays. Paint prevents moisture from penetrating the wood, thus preventing rot and mold from reaching the wood surface. A well-painted house lasts longer, requires less maintenance, and looks fresher, which can increase its value. Paint also prevents damage and reduces the need for costly repairs in the long run. Additionally, with the right color and paint, you can improve the house’s energy efficiency and appearance. Painting is overall a worthwhile investment in the house’s maintenance and appearance. In a previous article (House Painting Price 2025), we explain when painting is timely:

“House painting becomes timely when surfaces look untidy, paint is flaking, cracking, or has worn thin. Mold spots on the paint surface or faded colors can also indicate that the paint is no longer providing adequate protection.”

When can you paint outdoors?

The timing for exterior painting depends on weather conditions, temperature, and paint type. Generally speaking, the ideal time for exterior painting is from May Day to Midsummer, but late summer and early autumn also work well for exterior painting. Spring brings suitable temperatures, and often in autumn there’s still enough warmth in Finland for painting.

So can you paint a house in winter? Winter painting is possible, but it requires preparation with the right materials and careful monitoring of conditions. It’s important to ensure that the temperature is high enough, the surface is dry, and that moisture or frost doesn’t threaten the paint surface. If these factors cannot be controlled, it’s better to wait for spring or summer.

When should house exterior painting be done?

Previously, it was thought that the best time for house painting is from May Day to Midsummer, but nowadays these painting conditions continue considerably later. This is because in winter the house structures dry well, and Finland’s climate is at its driest from late spring to early summer. The best painting temperature is usually between 5 and 30 degrees. In weather that’s too cold (below 5 degrees), the paint won’t dry properly, and in weather that’s too hot (above 30 degrees), it can dry too quickly, which can lead to an uneven surface.

We’re often asked whether you can paint outdoors in autumn. Usually in early autumn the temperature is quite reasonable and rainfall isn’t too heavy. The extreme weather conditions of late autumn and winter should be avoided, as they can affect the paint’s drying and durability.

At what temperature can you paint outdoors?

The recommended temperature for exterior painting is usually above 5 degrees and below 30 degrees. This temperature range ensures that the paint adheres well and dries evenly. Painting below 5 degrees is not recommended, as the paint won’t dry properly and can remain sticky or crack. Above 30 degrees, the paint can dry too quickly, which can cause an uneven surface. Hot direct sunlight can also dry the paint before it has time to spread evenly.

It’s best to avoid painting in direct sunlight and paint preferably early in the morning or evening when the temperature is slightly lower and the weather is milder.

Can you paint outdoors if there’s frost at night?

It’s not recommended to paint outdoors if there’s frost at night, even if the daytime temperature is warm enough. Paint needs time to dry and harden, and in freezing temperatures the paint’s drying slows down or stops completely. If the paint doesn’t have time to dry properly before frost, it can remain sticky, crack, and come off later. If there’s frost at night, you should wait until the nights warm up.

What happens if you paint in weather that’s too cold?

If you paint in weather that’s too cold, i.e., below 5 degrees, the paint won’t dry properly and can remain sticky. This is because in cold weather the paint’s solvent doesn’t evaporate quickly enough, which prevents it from hardening. The paint can also crack or come off because it hasn’t had time to adhere properly to the surface.

Cold air also generally makes the paint harder to spread. In cold weather, paint can become thicker and more difficult to handle. When you ensure that the weather is warm enough for painting, the paint is easier to handle and additionally it has time to dry properly and thus also provides more durable protection for the building.

What happens if you paint in weather that’s too humid?

A good rule of thumb for suitable painting weather is that the humidity percentage should be below 80%. As we state in a previous article:

“If the air humidity is too high or the temperature too low, the paint film’s drying slows down and the film doesn’t form properly. This makes the paint film weak and it may crack. It’s worth being careful with weather conditions.”

If you paint in weather that’s too humid, the paint can dry slowly, remain soft, or run. This can lead to an uneven surface and the paint surface coming off.

Sometimes people ask why paint blisters. Paint blistering is usually caused by moisture in the base surface, poor preparation work, or incorrect painting conditions.

Can you paint a house a different color?

You can paint a house a different color if the plan allows it. In some municipalities or cities there may be restrictions on the house’s color, so when planning a color change it’s good to verify this with the local building control.

If the permit matters are in order, the house can be painted a completely different color. However, this requires good preparation. Choosing a new color can give the house a fresh look and make it even more beautiful, but at the same time it’s important to ensure that the painting is done correctly so that the final result is as desired. If you change the color radically, such as from light to dark or vice versa, it may require more coats of paint. A dark color can easily show through previous colors, so it may be necessary to use a primer that prevents the old color from showing through.

How long does it take to paint a detached house exterior?

Painting a detached house takes on average 2–8 days, and the duration depends on factors such as the house’s size, height, surface area to be painted, and the amount of preparation work. Weather conditions also have an effect, as favorable conditions speed up the work. If the house has many details or areas that require protection, painting takes more time. Also, if old paint needs to be removed or the house needs thorough mold cleaning, the job takes longer. In smaller houses and good weather conditions, however, painting can be completed in a few days.

How long does exterior paint take to dry?

Exterior paint drying time depends on many different factors, such as the paint’s quality, air temperature and humidity, and the surface being painted. Oil-based paint can take weeks or even months to fully dry, while water-based paint can dry to the touch in hours under good conditions.

Good, warm weather speeds up drying. If paint has been applied thickly, the drying time can be longer. It’s good to check the paint manufacturer’s instructions, as paints from different manufacturers can have different drying times.

How much does house exterior painting cost?

We’re often asked how much house exterior painting costs. We answer this question in our previous article House Painting Price 2025:

“House painting price usually ranges between approximately €5,000–€20,000.”

The price of house exterior painting varies according to several factors, such as the house’s size, paint quality, location, and possible preparation work. The price takes into account the house’s surface area and the number of paint coats. For example, in new houses it’s usually recommended to paint twice so that the surface lasts better.