“Why Is There Moisture on My Windows?”

“Why is There Moisture on My Windows?”

“Why is There Moisture on My Windows?”

This is a common question asked by many homeowners annually in the winter when the temperature drops. More often than not, people with homes that are less than 20 years old ask the question, or people with homes that are much older with newly installed windows. While the simple answer would be to just blame the windows, it is actually much more complicated than that.

For those of you that are not meteorologists, Wikipedia defines the dew point as “the temperature below which the water vapor in a volume of humid air at a constant barometric pressure will condense into liquid water.” Have you ever had an ice-cold glass of lemonade outside on a warm, humid day? Did you notice how the outside of the glass accumulated moisture? The reason that the water collected on the outside of the glass has everything to do with the dew point.

“So what does this have to do with my windows?” you might ask.

When discussing window condensation with homeowners, I always tell them there are two parts to solving their window moisture problems.  One part is my job, and one part is their job.

The first part (my job) is to make sure that the home has windows with a high quality glass package that will keep that glass temperature as high as possible. It is important to set realistic expectations at this point. When the temperature outside is 0° and the inside temperature is 70°, it is unrealistic to expect your inside glass temperature to be 70°. Typically, depending on the quality of the window, the inside glass temperature will be somewhere between 30° and 55°. Obviously, the warmer it is, the better. This is important because, if that glass drops below the dew point, you will see moisture appear on the glass.

The second part (the homeowner’s job) is to control the humidity levels in the home in order to keep the dew point as low as possible. There are many sources of humidity in the home, including humidifiers, heating systems, cooking, showers and baths, plants, pets, and even our bodies. All of these things contribute to the amount of moisture in the air inside our homes. As newer homes have been built tighter with less air leakage, and older homes are being retrofitted with tighter energy efficient products, this moisture cannot escape to the outside like it used to be able to.

So what can a homeowner do?

During the winter months, carefully monitor the humidity levels in the home. The following chart shows where your indoor humidity levels should be based on the outdoor air temperature.


Outside Temperature (°F) Inside Relative Humidity (%)
-20 15-20%
-10 15-20%
0 20-25%
10 25-30%
20 30-35%


Another solution that has proven to be very effective is to use a heat recovery ventilator (HRV) to exchange the moist inside air with the dry outside air. These systems work by drawing the warm moist air from the house into the unit through your cold air returns, sending it to the outside of the home through a duct, and then drawing cool dry air from the outside back into the house to replace it. An HRV can be purchased from your local heating and cooling contractor, who will typically do the installation and adjustments required.

In addition to maintaining lower humidity levels, open any heavy curtains and move furniture away from windows that may block air circulation. Also, keep plants out of your bow and bay windows in the winter.  Be sure to use an exhaust fan in any bath or shower areas to take the moisture outside of the home, because that moisture doesn’t just stay in the bathroom.

If all of this sounds like a lot of work, or if you like to have a little more humidity in the air than what is listed above, you should expect to see some moisture on your glass. If you have wood windows, you can expect this moisture to seep into the sash frames and damage the finish, rot the wood, or grow mold along the edge of the glass.

However, if you have windows that are made of fiberglass or vinyl, this moisture will typically dry up once the weather outside warms up or the humidity level in the home drops, without causing damage to the finish or function of your window.

To alleviate the issue of window condensation, consider installing Infinity Fiberglass Replacement Windows. Contact Callen to schedule a free consultation.

by Mike Wood, Sales Manager



Exterior Home Improvements: Where to Splurge

When planning an extensive remodel like a roof or window replacement, the number of offered options, and decisions you have to make, can be overwhelming. While in the long run you want to spend the least amount possible, it’s hard to know when it’s okay to go cheap and when something is worth a bigger investment. When it comes to home remodeling, Callen experts believe there are three home elements worth splurging on.

Exterior Home Improvements: Where to SplurgeWindows

While you may think you’re saving money by installing low quality, cheaper windows, the opposite is true. These cheaper versions are not nearly as energy-efficient as high-quality wood or fiberglass windows, so you will end up spending more money in the long run due to higher energy costs. In addition, the design options are much more limited, so it may be harder to get the customized style you’re looking for with lower quality windows.

Entry Doors

Many people don’t realize the impact a beautiful entry door can have on the appearance of a home. A sturdy, attractive front door draws the eye and gives off a welcoming vibe that adds to a home’s curb appeal. It’s also a great investment, as you will get back almost all you put into it when you sell. In addition, a well-built, durable entry door helps keep out the Wisconsin elements as well as intruders.


Your roof is your home’s shield and should be composed of materials of the highest quality. The strength and durability of roofing shingles have increased over the years, and there are now a good variety of affordable styles and materials available to help customize just the right look for your home. While high-quality roofing is an investment, it’s worth it knowing you’re protecting your largest investment of all: your home.

Stay tuned for a future blog with ideas on where to cut corners to save your exterior remodeling dollars! If you got in over your head with your latest remodeling project and need the expert help of a top remodeling company, Callen Construction has the experience to get you back on track. Give us a call today at 414-765-2585 to find out how we can help.



Tips for Home Winterization

Winter weather will be coming to Wisconsin before too long, so now is the time for area homeowners to prepare their homes for what can be a harsh time of year. Homes can be winterized with these tips from Callen professionals.

Tips for Home WinterizationOutside

  • Homeowners should make sure they have the necessary tools for the season in good working order: shovels, ice melting salt, and a roof rake for removing snow from the roof to help reduce ice damming issues.
  • Checking windows and doors for air leaks should start with a visual inspection of the exterior. Where the old caulking has failed, there will be a gap between the window or doorframe and the home’s siding. If your home has single-paned windows, look for damaged glazing, which is the hard putty that holds the individual panes of glass in place.
  • Clean gutters of any debris, which could add to ice damming issues. Consider seamless aluminum gutters and larger aluminum downspouts to reduce the amount of ice build-up and the possibility of leaks and damage.
  • Water is the enemy to your exterior chimney. Water getting into the masonry, freezing, and then causing failure gets costly to fix. Make sure the concrete cap or crown on the chimney has an overhang and is not cracked.
  • Make sure the flue that vents your furnace and water heater has the proper size liner in it, and that it is in good condition.
  • When the ground freezes, animals that normally seek shelter and food underground may instead cause damage to trees and shrubs. Flowering crab trees and burning bushes are especially susceptible. Protect plants with either wire or netting across or around the plant.


  • Check your furnace filter and replace it needed. Now is also a good time to have the furnace inspected and tuned up.
  • Regarding the air conditioner, turn off the breaker for the A/C and clean it thoroughly and properly.
  • It is necessary to make sure the fireplace chimney is clean from soot before using it this season to prevent a chimney fire. Also, be sure you close your fireplace damper when not in use. Otherwise the heat you are paying for while running your furnace is going up the chimney.



Roof Remodeling Tips

A roof is more than just the “hat” that finishes the look of your home. “The roof is arguably the most important component of your house; after all, it helps protect you from the elements,” said Lance Dahl, CR, exterior product specialist with Callen Construction in Muskego. “Before you make any decisions on potential roof replacement, make sure you understand all of the various components of this type of project.”

roof remodeling tips from callen constructionFirst, keep up appearances. In planning your next major remodeling project, don’t forget to reflect on the look and style of roofing materials. “When you consider that the average roof comprises 40 percent of a home’s visible exterior, you want it to look attractive,” he said.

Next, you’ll want to sneak-a-peak. In other words, inspect your roof from a safe vantage point using binoculars. “Specifically look for cracking, curling, and missing shingles, and if your roof is made of asphalt shingles, also look for areas that seem to lack granular covering,” Lance said. “You can examine your roof from the inside, too. Visit your attic space and use a flashlight to look for water stains that may indicate a growing roof leak.”

Check with your local municipal building department to see how many times you may re-cover an existing roof with another layer of similar materials. Some communities only allow two layers of roofing material, and require any additional layers to be torn off before more roofing can be installed.

Next, provide your contractor with a picture. “At Callen, we are able to use a digital photo of your home and show you a variety of options for the house featuring different roofing materials,” he said.

Regardless of the project size, all work to be done needs to be explained in writing. “You should be given a detailed proposal that describes the type of roofing material and color; other materials to be used; and the scope of work to be done,” Lance said. “It is important to specify whether the existing roofing will be removed or covered with a layer of new shingles, and to state who will be responsible for installing new flashing and vents. Most importantly, make sure the proposal indicates an approximate starting time and completion deadlines.”

According to the Asphalt Roofing Manufacturers Association, asphalt shingles are installed on approximately four out of every five residential roofs in the United States. Asphalt products are available in two types – organic and fiberglass – and in a wide variety of colors, styles, and visual textures. Organic shingles are made of cellulose fibers, such as recycled waste paper or wood fibers, while fiberglass shingles are made of glass fibers. “Both shingle types are covered with an asphalt coating and surfaced with weather-resistant mineral granules,” he said.

While asphalt shingles are by far the most popular option, consider the alternatives. “Do you love the appearance of cedar or redwood roofing, but worry about fire safety? There are fire-resistant wood shingles, or metal and synthetic products that mimic the look,” Lance said. “Such products can also match slate and tile roofs. Real clay or concrete tiles often appear in Southwest-style or Mission-style roofs. If you desire this look, you will need to make sure your home can adequately support the additional weight.”

Finally, it’s important to vent a little. “Attic ventilation ensures that your roof has a long and functional life,” he said. While ventilation requirements vary by region, the National Roofing Contractors Association generally recommends a minimum of one square foot of free vent area for each 150 square feet of attic floor.

Replacing a roof is a major investment, so make sure you stay as informed as possible and weigh each of your options carefully before making decisions,” Lance said. “In the end, your new roof should last at least 20 years, so it’s important that you’re happy with the products selected.”