painting exterior wall

Exterior House Painting, Window Washing, and other Chores Around the Home with the ennoLogic eT650D Infrared Thermometer

Using Your ennoLogic eT650D to Measure Surface Temperatures for Exterior House Painting, Window Washing, and other Chores Around the Home

Aside from the great uses of the ennoLogic eT650D Infrared Thermometer in the kitchen, it is a powerful tool you can use to help you get the best out of other chores around the home. You can use it to check if conditions are right before you start with chores. You can check for acceptable surface temperature before you start with exterior painting or window washing.

Exterior Painting

Certainly, you need cooperation from the weather when it comes to the exterior painting of your house or outbuildings. The weather should be clear, with no threat of precipitation, and very little wind. A light breeze is fine. But, anything stronger and the air movement can adversely impact the final results of your work.

As a general rule, the temperature should be above 50°F (70° is ideal) and no higher than 85 or 90°F for best results. It is also helpful if the humidity is less than 60%.

Obviously, you want to avoid rain for as long as possible after the paint has been applied. You should also try to avoid painting any surfaces that are in direct sunlight.

But What About the Temperature of the Surface You Are Painting?

Did you know the temperature of the north side of a house in the early morning can be twenty or more degrees cooler than the relative air temperature? Let’s say your target to begin painting is when the air temperature reaches 50° or 60°. Then you start on the north side of the building. By doing this, you may be starting before the surface temperature has warmed up properly. It should be within the correct temperature range before the application.

It also does not help if you move to paint an area that has just been in the full sun. Even if already in the shade, the surface temperature may be well beyond the upper limits for a quality outcome.

Surface temperatures have a serious impact on the longevity, look, and adhesion of paint finishes. Too cool or too hot can impact the bonding that happens chemically between the paint and the surface being painted. This leads to problems such as bubbling, peeling, cracking or the build-up of moisture under the paint surface.

Simple tips to follow are to paint in late spring or early fall. Painting should be done typically well after the last spring frost date. Additionally, it should also be two to three weeks before the first expected fall frost.

Avoid painting close to sunset on days with the evening and overnight temperatures are below 50°F. You want to give the paint adequate time to dry for at least two to three hours. This allowance gives you time before temperatures begin to fall and/or dew begins to rise.

Using an Infrared Thermometer in Checking Surface Temperature Before Painting

Use your eT650D infrared thermometer to determine the precise temperature of the surface you are about to paint. Particularly if these are surfaces which have not yet been warmed by the sun in the morning. Add to that surfaces which have recently gone into shade after sun exposure. It is a good idea to sample the temperature across a given surface. Take note that cooler areas can be found near vegetation, in shaded areas, or close to the ground.

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Try to apply paints when the surface temperature is as near to 70 degrees as possible. In some instances, this will require that you begin painting as soon as the dew is dry. This is to give the paint time to set before exposure to the sun. Sometimes, an overcast day with very low chance of rain can be your best painting day. This is true so long as the humidity doesn’t get too high.

There are other factors which affect the temperature of an exterior surface as well. For instance, an aluminum surface may heat up much more quickly in the sun than a stucco, plastered or wood surface.  Each surface is different and requires different preparation and considerations before painting can begin.

Window Washing

Window washing follows the same general rules as painting when it comes to sunshine and temperature, but there are some key differences.

A Warning Before You Start Washing Your Windows

When you are washing large windows, especially if you are spraying them down from the outside, it is critical to determine that the water temperature of the sprayer is fairly comparable to the temperature of the glass. A cold garden hose sprayer aimed at a hot pane of glass can cause the window seal to rupture and can even cause the glass to break.

There is less risk of breaking the glass with water hot from standing in a garden hose in the sun, but any dramatic temperature differential between the water and the glass can cause leaks and ruptures to sealed solid install windows.  Removable windows are less problematic because you can take them out of their window frames for easy washing indoors.

Helpful Tips to Lessen the Risks in Window Washing

Always wash windows that are on the shady side of the house, and try to wash windows before exposure to sunlight or at the opposite time of day from their sunlight exposure. For example, east facing windows can be washed around the time of sunset and vice versa.

Washing windows that are in direct sunlight can not only break the window (see above) it also generally leads to smearing and streaking as the sunlight and relatively higher temperature of the glass dries the cleaning liquid too quickly before you can properly wipe them clean with a squeegee, newsprint or rag.

Using the ennoLogic eT650D Infrared Thermometer to Check Window Glass Surface Temperature

Your eT650D temperature gun can give you accurate readings for any window glass surface, and you may find that a single pane of glass has a range of temperatures where sunlight, shade or reflective surfaces nearby impact the glass. A sunny southern exposure with a wooden deck surface can easily reach 130°F on a sunny day, and a window which overlooks that deck can get to temperatures nearly as high, particularly if the window extends down to the floor level. The heat from the deck will literally bounce up onto the glass.

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Easily take the readings you need for successful household maintenance projects.

10% OFF the eT650D IR Thermometer with Coupon Code CHORES10


Don’t assume that because you are washing the interior of a window that it is not as hot as the outside of the window. Glass conducts heat readily, which is why we need double-paned windows to at least work to reduce heat and cooling loss through windows. As a general rule, as in painting, you want the glass as close to a mean room temperature of 70 degrees as possible when washing windows, and slightly cooler exterior temperatures when using an outdoor hose attachment and sprayer for window washing.

No matter what exterior painting or clean up job you are getting ready to tackle around the home, you’ll find the perfect tool to help you get all the information you need before you begin is the ennoLogic eT650D dual laser thermometer.

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