Window Replacement Videos
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Replacement windows affect the look of your home. They also have a major impact on energy usage and comfort. When you’re considering replacement windows, consider the materials, shape, and functionality. You want to make sure each window makes your home inviting, increases efficiency, and keeps it secure. Take a closer look at our vinyl replacement window options!

Replace your windows ONE time with ProVia’s durable, long-lasting windows. Your choice of new replacement windows not only affects the architectural look of your home but has a major impact on your energy usage and comfort.
You don’t need to sacrifice strength at these critical barriers to your home. Zephyr Thomas offers the most technologically advanced materials for maximized strength against harsh weather, intrusion, and health hazards.
If you are looking for vinyl replacement windows in Lancaster, you should know that all of our windows are Energy Star® and National Fenestration Rating Council (NFRC) certified. Zephyr Thomas also carries the finest fiberglass entry doors Lancaster PA has to offer, so check out our door selection as well!
Simply put, ProVia’s windows are top-of-the-line, will work hard for you, and will perform beyond your expectations. When searching for replacement windows in Lancaster, PA, you will find it is the most sensible window solution for your home.
You may be looking for a window equipped with advanced engineering that offers exceptional energy performance, safety, and security, is virtually maintenance-free enjoyment, and offers ease of operation. ProVia incorporates ALL of these important elements into one window.
Zephyr Thomas is your authorized Lancaster windows dealer for ProVia. ProVia’s Aspect Series is the superior window choice for your family, home, lifestyle, and budget.
A bay window consists of three window segments that project out from the wall to the outside at a sharp angle, most often either 30, 45, or 90 degrees. A bay window can consist of a number of different configurations.
The most common is a quarter-half-quarter layout with a picture window as the center window and either casement or double-hung windows as the end windows. We call these end windows “flankers”. Bay windows typically have a wider sill, called a seatboard, which can be a wonderful little nook for any number of décor ideas.
A bow window is similar to a bay window in that it also projects out from the wall to the outside. However, a bow window curves instead of being at an angle. A bow window can consist of several different configurations. Bow windows are divided into even sections, called lites.
The most common types are 3-lite, 4-lite, and 5-lite bow windows. The operating lites are typically casement or double-hung windows and the fixed lites are either picture windows or fixed casement windows. The end windows, or flankers, typically operate, or all the windows can be fixed picture windows. A bow window also has a window sill, like a bay window.
A casement window is most commonly recognized as a crank-out window. These windows are often seen as part of a bay or bow window, but these are not the only places where casement windows are an appealing option.
Above a kitchen sink or in a space where you are really looking to maximize the opening area of the window are great places for casement windows. Casement windows can be one single window or multiple lite, depending on the opening and application.
Sliding windows do just that, slide. Sliding windows have many great applications, but are probably most commonly recognized as part of a sunroom or porch enclosure. These windows allow you to open either the left or right side of the window. Most commonly seen in the 2-lite option, these windows can also be 3 lites, with the end lites operating and a fixed lite in the middle.
Double-hung windows are probably the most common style of window. These windows consist of a top lite (or sash) and a bottom lite (or sash). Double-hung windows can typically be opened from the top or the bottom. This is a versatile window style that can be used not only in your home, but also works well for additions, sunrooms, and porch enclosures.
U Factor: U Factor measures thermal insulation. The U Factor indicates how easily heat will flow through the window, whereas the R Factor indicates the opposite, how well the window will resist heat flow. The lower the U Factor, the better a window insulates.
Solar Heat Gain Coefficient (SHGC): SHGC measures the amount of solar radiation admitted through a window. The lower a window’s SHGC, the less solar heat is transmitted into the house and the easier it is to keep your house cool in summer.
On the other hand, in northern climates, a higher SHGC can provide beneficial passive solar heating in the winter. Aspect offers a variety of high-performance Low-E glass packages with varying SHGC ratings to suit your needs, based on your needs.
Visible Transmittance (VT): VT measures the percentage of visible light that is admitted through the window. High-performance glass packages have been designed to enhance a window’s thermal performance by blocking ultraviolet and infrared light while maximizing visible light transmission. Clear glass itself blocks about 20% of visible light.
All of ProVia’s windows are tested to standards set forth by the American Architectural Manufacturer’s Association (AAMA) for structural performance. Air infiltration, water penetration, and structural wind loads are three commonly referenced tests.
What Is Air Infiltration? The amount of air that passes through the seals of a window’s operating sashes per minute, per square foot of window. Using a typical vinyl window would be like having a hole in the wall of your home, leaking 9.68 balloons worth of air per minute!
High-quality, energy-efficient windows have air infiltration ratings lower than 0.3. ProVia’s Aspect Series windows achieve an excellent air infiltration rating of 0.05 or below.

Super Spacer® Aspect Windows: ProVia uses advanced Super Spacer® technology as a standard to create insulated glass with a warm edge around the perimeter. The edge of the glass is typically the coldest spot on the window and can be prone to condensation.
Other windows use glass panes with rectangular aluminum that conducts the heat away from the inner pane of glass, which results in a cold edge. Super Spacer® is a non-metallic, structural foam spacer.
Super Spacer® blocks heat escape, dramatically reduces condensation, and offsets the effects of temperature changes that prevent stress cracks.
INNERGY® Thermal Reinforcements: In addition to Super Spacer®, ProVia also uses INNERGY® thermal reinforcements in their windows instead of aluminum. This is an innovative and energy-efficient alternative that is 700 times better than aluminum in material comparisons on thermal performance.
Choose the glass, grid, and color options that are perfect for you and your home– the possibilities are nearly endless. The flexibility of our window designs and the ability to integrate any design and size into your home allow for optimum cost-effectiveness and energy efficiency when you need new windows in or around Lancaster County. The choice is truly yours– style, size, color, and an assortment of specialty window shapes, grid styles, and glass options will provide a look designed exclusively for your home.
Download the Aspect (PDF) brochure for more information and features. We have other window series and options available, so visit our showroom or call for more information.




EnergyStar Window Tax Credit Program Changes
National Fenestration Rating Council (NFRC)
Residential Energy Services Network (RESNET)
Environmental Protection Agency (EPA)
Zephyr Thomas recently completed some upgrades to my home including new storm doors, window, gutter guards and multiple basement improvements. From the initial consultation with Ryan through the quality workmanship done by Chris and Derek, I was very pleased with the communication, professionalism and work ethic of the company. The results were exactly as I had requested. I will be contacting them again for future projects!
- Pamela Eisenhauer
For the past few years, we have had a window that has leaked, and have put it on the back burner because we have had other bigger problems with the house. Recently, some of the wood from the window fell down, and we realized that we had a massive termite infestation. After taking care of the termites, we had Zephyr Thomas come out and look at the window and gave us a very fair price but told us that they would not be able to know the extent of the damage from the termites until they actually opened the wall up. We totally understood and expected the worst. When the day finally came, Derek and Chris came out to replace the window and by some miracle, the termites had only eaten the window frame. They were shocked, we were shocked, everyone was shocked. By some miracle what we thought was going to be a massive job turned out to be a very simple window installation. Derek and Chris were very professional, were able to get the job done very quickly, and even left a fun note on our driveway with the sidewalk chalk that I had left out from my three year old. To top it off, we got a call back later saying that because they needed less supplies than they had originally planned for they took money off of our final price. We were so happy with their service and so impressed with how fair and honest they were with their pricing. We will definitely be using them again in the future!
- Mallory Salador
We had two dormers installed in our garage by Zephyr Thomas. Josh Lapham came to our house, took measurements, provided the estimate, and detailed drawings. The project was completed in about a week and the work was done very professionally. We are very happy with the final product and with the entire process.
- Greg Gilmartin
Zephyr Thomas just completed a long overdo upgrade to the front of our home. They installed new shutters, new fence sections, new outdoor lighting, a flagpole and address sign. The installers were very skilled and completed the work in just a few hours. The salesman is very knowledgeable, responsive and professional. This is our 3rd project with this company and we highly recommend them!!
- Kevin Kingma