Therm-O-Loc
We Ship to All 50 States!
Quality, Locally-Made Vinyl Windows!
Affordable, low maintenance, energy-efficient windows custom-built right here in South Dakota.
Therm-O-Loc vinyl windows offer energy efficiency, lower utility bills, improved comfort, and UV protection for your home’s interior. We serve homeowners and contractors across the US with dependable, efficient windows.
Contact The Window Shop today to request a consultation and a FREE estimate to see how we can add to the beauty and comfort of your home!
(605) 996-6777
40+
Years building high-quality, custom vinyl windows right here in South Dakota!
About Therm-O-Loc Windows
Therm-O-Loc Windows has been building vinyl windows since 1984, using only top-grade virgin vinyl from VEKA, a family-owned global supplier of extruded vinyl products. We are committed to product excellence and customer service, and constantly strive to improve our windows. Our 1000 series Double Hung, Slider, and Picture windows and 300 series Casement windows feature LoĒ-272™ glass and LoĒ-366™ glass that delivers year-round performance and comfort, whether it’s -20° F or 110° F in the shade.
Therm-O-Loc Windows:
- Reduce heating and cooling costs.
- Increase comfort in hot and cold weather.
- Protect interiors from UV rays.
- Reduce condensation.
We offer custom-sized windows in various styles and colors, and ship anywhere in the U.S. We welcome residential homeowners, business owners, and contractors.
Energy-Efficient Vinyl Windows With Plenty of Styles, Sizes, and Options
Choose from a variety of window styles, colors, and options to fit your budget and taste. We custom-build your windows to exactly match the size and style that you want.
Our vinyl windows are built with 100% virgin vinyl to give you many years of dependable and hassle-free use.
Double Hung
A favorite choice among many homeowners, double-hung windows feature two tiltings and movable sashes to make regular cleaning and ventilation a breeze.
Casement/Awning
Casement windows hinge on the side and open with a crank. Awning windows are similar, except they hinge at the top and let you enjoy a fresh breeze in your house even during heavy rain.
Slider
Slider windows combine refreshing breezes with an attractive contemporary style. Two moving sashes with continuous handle rails slide on brass rollers, making it easy for you to open and close your windows.
Bays and Bows
Three or more windows that extend outward from the house. Bay and bow windows are an excellent choice for opening up a room and increasing the light and the viewing angle — up to twice the field of vision.
Specialty
Specialty windows are custom made to add instant character and give your home a unique touch. Different shape options, including custom and combination options, allow for nearly limitless creativity.
Therm-O-Loc Window Components
- 100% virgin grade-A first-generation vinyl.
- Multi-chamber frame and sash create an insulated air chamber.
- LoĒ high-performance insulated glass.
- Constant force system operation.
- Dual cam action lock and keeper system.
- Dual weatherstrip provides energy tight seal.
- Standard sash pivots for easy inside cleaning.
- Cardinal’s XL Edge Spacer helps protect against condensation.
- Extruded ergonomic large lift rail.
- True sloped sill.
- Triple weatherstrip at sill area.
Colors to Match Your Scheme
White
Interior
Interior
Interior
Black
Interior
Light Oak
Interior
Dark Oak
Interior
White
Exterior
Beige
Exterior
Clay
Exterior
Bronze
Exterior
Black
Exterior
Terra Bronze
Exterior
Green
Exterior
Grids Add a Classic Appeal
In Colonial White, Contoured White, Colonial, Prairie, Diamond, Contoured Dark Oak, Contoured Light Oak & Narrow Brass
Custom Glass Options, the Pinnacle of Customization!
Clear
Low-E (soft coat and hard coat)*
Coated Glass
Tempered Glass
Insulated Glass
Tinted Glass
Laminated Glass
Decorative Glass (Standard and Custom)
We can provide you with custom bends over 600 vinyl extrusions to exact radius specifications.
*LoĒ-272™ glass and LoĒ-366™ glass delivers year-round performance and comfort, whether it’s -20° F or 110° F in the shade.
Warranty
All vinyl parts are guaranteed for a lifetime. The insulated glass units are warranted against all defects including fog-up for 20 years.
ENERGY STAR® Certified
Install ENERGY STAR certified windows and reduce your heating and cooling expenses.
NFRC Certified
Therm-O-Loc windows have been rated and are certified in accordance with National Fenestration Rating Council procedures.
Vinyl Window Maintenance and Care Guide
Key Tips to Keep in Mind:
Minor Surface Marks:
Small scratches or scuffs may appear on vinyl surfaces over time. These can typically be smoothed out using a fine polish designed for vinyl materials.
Water in the Sill Area:
It’s normal for some window designs to collect water in the sill area. These systems are built to channel water outside before it can enter your home. Water in the sill isn’t a concern unless it overflows into your interior. If this happens, inspect the sill to ensure the drainage holes aren’t blocked by debris.
Dealing with Condensation:
Moisture buildup inside the window is often due to high indoor humidity. To reduce this, consider using a dehumidifier or turning on exhaust fans during activities like cooking. Note: Interior condensation is not typically considered a warranty issue.
Key Tips to Keep in Mind:
Taking care of your windows year-round helps them stay efficient and looking great. Follow these maintenance tips:
Clear the Sill Track:
Remove any dirt or buildup regularly to help water drain outside as designed.
Check Weep Holes:
Make sure these small drainage openings are clear so water can escape properly.
Inspect Caulking:
Check the exterior caulking around the window and replace it when it starts to crack or peel.
Hardware & Weather-Stripping:
Clean and test the functionality of moving parts and seals regularly. Repair or replace as needed.
Clean the Seals:
Dirt on weather-stripping can prevent a tight seal. Use mild soap and water to clean, then dry.
Moisture Management:
If you notice water inside or around your windows, find the source immediately and resolve it to prevent damage.
Control Indoor Humidity:
Keeping humidity at a moderate level helps prevent window-related moisture issues.
Frequently Asked Questions
If you have a question for us, please use the link below.
What are the advantages of vinyl?
Vinyl windows are an affordable, low-maintenance option that provides lasting energy efficiency in all weather conditions. As the most popular choice for replacement windows today, vinyl outperforms wood, aluminum, and composite/fiberglass alternatives.
However, it’s important to recognize that not all vinyl is the same. While older vinyl windows were known for warping and fading over time, Thermoloc Windows uses uPVC (unplasticized polyvinyl chloride) rather than standard PVC. This advanced vinyl material is engineered for superior strength, durability, and resistance to the harmful effects of UV light.
How long does it take to install new windows?
The installation time varies depending on the number of windows being replaced, but our team works efficiently to minimize disruptions to your daily routine.
Can I order custom-sized windows from your company?
Yes, we can accommodate custom window sizes to fit your unique specifications.
Do you offer energy-efficient windows?
Yes, we offer energy-efficient windows that can help reduce your energy costs.
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Therm-O-Lac Manufacturing
40809 265th Street
Ethan, South Dakota 57334
Give us a call! We’re happy to answer your questions!