Window Films – What to Look For

Films are another great option for improving the efficiency of your homes windows. This option is most commonly exercised when a homeowner is looking for an upgrade without necessarily replacing the glass or other aspects of the window. Window films are commonly sold as extensions to your existing windows. 

Window Films

Window films are exactly what they sound like, films applied to your homes windows to help reduce the energy lost through your windows and glass. These films block against solar heat gain, and protect against UV exposure. Films are most commonly adopted in southern climates because they can also block the suns heat in the winter. 

They are also particularly useful for homeowners who are looking for an unobstructed view out of their window and don’t have a need to prevent glare or heat gain. They are also an excellent choice if you have a furniture layout that blocks a portion or all of the window. Finally, they are always a recommendation for public buildings such as art galleries or museums who are trying to prevent color from being washed out of their exhibits. 

Window films consist of three layers: 

Window Film Cross Section

Films typically have three layers: an adhesive layer that sits against the glass, a polyester film layer, and a scratch-resistant coating. You may also choose options such as tints, UV blockers, or thicker films that offer security. Low-e films are also emerging as an energy-saving option.

Window films are the first window attachment to be rated by the National Fenestration Rating Council (NFRC), which also created window labeling and ratings for consumers. The NFRC’s Window Film Energy Performance Label looks like this:

NFRC Sample Label

The effectiveness of these reflective films depends on:

·        Size of window glazing area

·        Window orientation

·        Climate

·        Building orientation

·        Whether the window has interior insulation.

Window films have some overall disadvantages:

·        Loss of interior light or visible transmittance

·        Extra care required for cleaning

·        Reflections

Energy Efficient Window Coverings – What to Look for

Our previous articles discussed window and glass efficiencies, warranties, and the top reasons to replace windows. This article will expand upon these topics and begin to cover some of the window coverings which will be able to reduce energy usage associated with heating and cooling, and make your home more comfortable year round. 

Most types of window treatments will result in energy savings, but the exact savings will depend on the type of attachment, the season, the climate, and how the attachment is used.

In addition to the window treatments discussed below, storm windows with low-e coatings are effective at improving thermal performance of windows and reducing solar heat gain.

Operable Window Coverings

Operable window coverings are by far the most popular choice in window treatments because they offer the flexibility to choose from having the window coverings open or closed.  This allows the homeowner to decide their level of privacy, maximize natural light, and to take advantage of solar heat benefits. 

Most common operable window coverings: shades, blinds, curtains, drapes, shutters

Interior Window Treatments

Window treatments come in a variety of different form and shape factors. This is primarily due to personalization – a great deal of personal touch can be applied when choosing these treatments.

Insulated Cellular Shades

Cellular shades are very common, but most people know them by how they look.

Insulated Cellular Shade Options and Variety

Insulated cellular shades are made of a pleated material designed to fold up like an accordion when they are fully open at the top of the window. These are beneficial when closed because the air inside the curtains acts as an insulation layer which can reduce heating costs in the winter. 

Insulated cellular shades typically offer the highest level of comfort, privacy, and energy efficiency measured by R-value 

Some cellular shades include the option of automation, allowing the blinds to open and close on a set schedule. The schedule can be seasonally optimized to reduce heating and cooling loads while maximizing natural light and home comfort.

Window Quilts

Window quilts have a sheet of quilted or knit material that can be opened by rolling and closed by unrolling. They typically fit snug against the trim, either on tracks, with velcro, or another mechanical attachment at the top of the window frame.

Their tight fit offers R-value increases similar to cellular shades, and they typically cost less. 


Window blinds—vertical or horizontal slat-type—are more effective at reducing summer heat gain than winter heat loss.

Because of the numerous openings between the slats of blinds, it’s difficult to control heat loss through interior window blinds, but the slats offer flexibility in the summer. Unlike shades, you can adjust the slats to control glare, light, and solar heat gain.

When completely closed and lowered on a sunny window, highly reflective blinds can reduce heat gain. Horizontal slat-type blinds can also be adjusted to block and reflect direct sunlight onto a light-colored ceiling. A light-colored ceiling will diffuse the light without much heat or glare, while allowing you to take additional advantage of natural daylighting.

Curtains and Drapes

Curtains are fabric interior attachments that are sized to fit the window, while drapes reach all the way to the floor.

A drapery’s ability to reduce heat loss and gain depends on several factors, including fabric type (closed or open weave) and color. With such a wide variety of draperies available, it’s difficult to generalize about their energy performance.

The most efficient curtain and drape combination is with a two layers. Two draperies hung together will create a tighter air space than just one drapery. 

What to look for in a Window Warranty

Just like every window is not created equally because of their NFRC rating, not all window warranties are the same either. 

Warranties on products are meant to both inspire confidence in the consumers perception of a product and to protect a consumer from any repairs or replacement costs associated with a product malfunction or failure during any warranty period.  

Warranties on new or replacement windows are critical in protecting your wallet from costly damages. Furthermore, warranties on the glass may be available and offered separately from your window based on the manufacturer. Below are some tips to help differentiate different warranties associated with windows. 

Questions to ask about Window Warranties when shopping for new windows

  • Do you offer a warranty on all your windows?
  • How long is the warranty valid for?
  • Does the warranty cover all parts? Only the Window Frame? Only the Window Glass?
  • Is the warranty limited or full?
  • Does the warranty cover labor?
  • How easy is it to register for the warranty?
  • How soon can I expect my window to be fixed or replaced while under warranty?
  • Is the warranty transferable (passed along to subsequent homeowners)?

Window Warranty Basics

Window warranties are NOT mandatory, which could leave you in a hot water if your new windows start giving you problems. We recommend asking your window installer the following questions to ensure your window’s warranty is right for your situation.

Do you offer a warranty on your windows? Since warranties are not mandatory, some companies may not offer or include a warranty for your windows. If your contractor does not offer any warranties with the installation, consider purchasing a warranty directly from the manufacturer. If neither option is available this should be an immediate red flag and should consider finding a different window contractor.

How long is the warranty valid for? The scope of warranties often differ by product, brand, or manufacturer. Some warranties may be a “lifetime” warranty, meaning they are valid forever. Others may only be valid for one, five, or 10 years, while others may last as long as 20! Always ask which parts and services are included with the warranty!

Does the warranty cover all parts? A window may seem simple, but depending on the function, it may have moving parts like in double hung or casement windows. A manufacturer’s warranty may or may not cover the glass, hardware (e.g. its lock, hinges), window screen, etc. Be sure to ask what parts are covered in your window’s warranty. Ideally, all parts are protected under your warranty and the labor associated with fixing any defective parts.

Does the warranty cover labor? Similar to covering the various parts of a window, a warranty may or may not cover its installation. Although you can rely on most companies to properly install a window (especially if they are a window and door company), your windows may be installed incorrectly and result in insecure seals or a malfunction. Common sealant failures are explained in depth by the largest sealant manufacturer if you are installing windows on your own.

Is the warranty a limited warranty or full warranty? Not every window warranties are the same. If your window comes with a full warranty then all parts should be replaced by the manufacturer or contractor in a reasonable amount of time at your convenience. A limited warranty is more strictly regulated and may only apply to certain parts or appeal to specific defects. Limited warranties offer less coverage than a full warranty and are only as specific in their coverage as the manufacturer or retailer wants.

Energy Savings Guide to Replacing Your Home Windows

This article will teach you how to take advantage of energy rating on your homes windows by understanding and utilizing the information regarding your homes zone rating, the window warranty, and the window efficiency claims. 

The most information regarding the effects of energy loss, heat loss, and solar reflectance for your windows is located on the NFRC label, like the image below. The NFRC (National Fenestration Rating Council) label illustrates the test results from an independent testing laboratory which will enable you to compare and understand the performance of your windows and a potential window replacement. While, independent testing results are not required by law from window manufacturers and installers, the majority of large residential and commercial window suppliers subject their products to this level of scrutiny.

 Therefore, the NFRC label is both your assurance that your windows meet specific energy regulations and a comparison tool to identify the replacement window for your need. The test and rating scale for NFRC labels is displayed below. 

NFRC Label Example

NFRC Categories

Energy Star: The shaded potions of the map show where a window meets Energy Star criteria. This unit passes muster nationwide.

Visible Transmittance (VT): Specifies how much light passes through; 0 is opaque, 1 is transparent. Glass with a VT of .60 or more looks clear. A VT below 0.40 gives things a grayish cast.

U-Factor: Measures how effectively a window stops heat flow. The smaller the number, the better the performance.

Solar Heat Gain Coefficient (SHGC): Indicates the ability of the glass to block the sun’s heat. The lower the number, the less heat gets in. In the northern zone (see map below), an SHGC of 0.32 or more can offset less-than-ideal U-factors up to 0.30.

Know Your Energy Rating Zone

In many instances, two windows that look exactly the same may not perform exactly the same. In short, not all windows are created equally. The differences between two identical windows can be seen more visibly by differences in the energy efficiency ratings. The Federal Law dictates specific efficiency ratings based on your geographic location. Below is a map which dictates the minimum level of efficiency based on your location in the United States. 

Energy Star Regions based on Efficiency

Perhaps the most important take away from this article should be that the minimum energy rating for your windows IS NOT the recommended rating. 

Colder climates such as the Midwest (Wisconsin, Minnesota, Illinois) it is recommended to have at least triple pane glass windows with a high solar reflectance rating (U factor) to offset the costs associated with cold winters and hot summers. 

Think of your windows as an investment, and with any investment consider the window and glass package that best fits your homes needs.

Energy Saving Tips

Try these tips for enhancing the performance of your window by improving the glass and insulation.

Low-e coatings: These transparent, micron-thin layers of metal reflect heat either toward the interior (in cold climates) or toward the exterior (in warm ones), depending on the glass surface they’re fused to. The can reduce heat loss (or gain) by as much as 35 percent, per information from the U.S. Department of Energy.

Inert gases: Air trapped between panes insulates fairly well, but if a gas such as Argon is used instead, performance improves by 16 percent. Xenon and krypton insulate even better than argon. These heavier gasses will improve the R-Value of your windows by at least 0.5 points.

Warm-edge spacers: Standard aluminum spaces conduct lots of heat through the edges of double-pane glass. Nonmetallic, warm-edge spacers bring those loses down by 10 percent, per Cardinal Glass, and make it more difficult for condensation to corm on inside panes.

For more information on why to replace your windows read more here.

Why Should I Install New Windows?

Install New Windows Or Miss Out On These Benefits

We’ve seen it a thousand times, a homeowner is looking to squeeze every last ounce of life from their existing windows and glass. Well, what most people don’t realize is how much an old, broken, or drafty window costs.  Sure a window is designed with a function in mind, like letting light in or providing you with a nice view when you do your dishes, but what you don’t realize is that it is also your first layer of protection from the outdoors.

Below is an itemized list which describes why you should be looking to replace your home windows.

Energy Rebates

No one likes paying taxes, but everyone loves a tax break! Depending on the state you live in, you may be eligible for a tax rebate or incentive when you install a new and energy efficient windows.  Not only would the government give you money to make your house look better it can even decrease your monthly heating and cooling bill.

Decreased Utility Cost

In addition to the aforementioned energy rebates, new windows or more efficent glass panes can drop your heating bill exponentially especially in the frigid Midwestern winters. This added energy efficiency comes from the windows being a better insulator than your old windows. The energy efficiency grade depends heavily on the type of window you are looking to have installed, as well as the side of the house it is on.

Environmental Benefits

Lets face it, we all get tired of the tree huggers telling you we need to save the environment, but let’s also be realistic. If we can reduce the amount of gas you burn in the winter because your new windows are insulating your home from the harsh environment, we call that two birds with one stone.

Leaky or Cracked Windows

I’ve seen it first hand. Many homeowner or renters will go entire seasons with broken panes of glass letting huge drafts of cold air in during the winter or all the cool air out during the summer. Don’t let this happen!  Replace your old broken or leaky windows with something new and economical.

Ease of use

If you have a double hung window that won’t even open up or down, why have one there at all? If your windows are broken or hard to open and even harder to close, look no further than replacing that old thing. Put something new in that windows place that will really make your neighbors jealous.

Beautification Factor

We at SlugWire aren’t sure if Beautification is a real word or not but we are going to go with it.  Put in a new window that you can be proud of.

Cost the Real Fear Factor

Yeah yeah, windows are expensive, but honestly would you rather be stuck with something that doesn’t work, doesn’t insulate your home, increases your heating and cooling costs, or is just plain ugly? All across the web, people are correctly stating that an improvement to your home is an investment that will pay off. Especially when it is something on the exterior, where people form a first impression.

Replace your old crumbling windows today with something that you will be proud of and something that will pay off for you.

Good Luck,


The SlugWire Experience

We at SlugWire have been working in the home improvement business for generations as we’ve mentioned here before.  And as an experienced home designer and home improvement contractor, we are always surprised at the lack of knowledge that new homeowners have. So to start things off, we are here to touch on the top 5 questions you need to ask your home improvement contractor.


Top Questions to Ask Your ContractorQuestions puzzle image for what to ask a general contractor

Whether you are looking for replacement siding, replacement windows, a new roof, or even a stump to be ground down you need to understand how your decisions impact your home. All of these tasks require a high degree of experience and expertise – something they don’t teach in school, but rather by working under someone who has experience. Because of this it is crucial that you address the following questions before you sign or pay for anything.


How Long Have You Been in Business?

In addition to verifying a contractor’s license and insurance status, you need to understand the level of experience the company has. I always tell my friends and family to be wary of a new contractor especially if they are a significantly cheaper than the competition. There could be reasons for this price cut, and you could end up paying for this in the poor craftsmanship that the installation team provides.

Do your research ahead of time and collect at least three quotes from different businesses. Don’t fall into the trap of getting charmed by a good salesman, and reach out to other professionals in your area for a second opinion.


Do you have a contracting License?

I can’t speak for the town that you live in, but I know that in Michigan, that the state requires a license, which is different from city and unique to each county. Each of these licenses requires different training and it will be different for each of our readers location. So again, do you research!

As a homeowner you need to make sure that they are licenses and experienced in each of the different locations, and that the licenses are up to date.


Do you have References?

Even if a contractor has all the relevant credentials, it wouldn’t hurt to check out their reputation online. See what customers have said in the past, and look for recent reviews. I know that I have referred many of my neighbors to the window contractor that we used for our house because they were very professional and fast. If you’re reviewing on Google, you may be able to reach out to a customer and ask them for additional details on their install job.

Roofing contractor on scaffolding

What to look for in a Home Improvement Contractor

Does the team working on my house have experience?

We all like to multitask, even business owners. Contracting companies will likely have many active jobs at a time. This isn’t a bad thing, only the truth to stay in business.  With many open jobs, it’s important to verify the quality is high and consistent.  This means making sure that the same people will be working on your project if required.  Be sure to ask questions such as:

  • Will the same team be at and working on my home each day?
  • May I meet the project manager at the start of each day to check in on the progress?
  • Do you work with subcontractors? Will subcontractors be working on my project?
  • How do you verify the quality of work completed?


How can I get in touch with you?

After agreeing to an installation job for siding, window, your roof, or any part of your home make sure that you can contact the right people. Make sure that you know what you are paying for and who to contact if you are unhappy or unsure of any aspect of the installation process.

Never settle for the sales line, or the number you called to get an estimate. Ask for the project managers phone number, the owners number, or someone who can help correct a problem. Be sure to follow this up with what the best times are to reach the contact, because after all you want them to work with you and not against you. Ask if he/she prefers to be contacted with a phone call, a text, email, or even in person. Understand that he is busy with his life and his job, and ask for a reasonable timeline for him, or someone who can help you, to get back to your needs or concerns.