Glass block windows offer a unique blend of style, privacy, and functionality for homeowners looking to upgrade their spaces. Whether it’s for a bathroom, basement, or any other room needing natural light without compromising privacy, these windows can be an excellent choice. While the installation process might seem daunting at first, with the right tools and know-how, it’s a project many homeowners can tackle themselves. This guide will walk through the steps of installing glass block windows, from measuring to the final touches, helping homeowners save time and money while achieving professional-looking results.
*We sourced costs in this article from contractor estimates used by Angi.
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Tools and Materials Required for Glass Block Window Installation
Before diving into the installation process, it’s important to gather all the necessary tools and materials. Having everything on hand will make the project run smoothly and efficiently. Here’s what homeowners will need:
Tools:
- Pry bar
- Chisel
- Circular saw or reciprocating saw
- Level
- Measuring tape
- Trowel
- Tuck pointer
- Utility knife
Materials:
- Glass block window
- Glass silicone
- Grout (optional)
- Mortar and sealant
- Shims and spacers
- Soft cloth
- Sponge
- Wide masking tape
- Work gloves
Some parts of the installation may require an assistant, so it’s a good idea to enlist help from a friend or family member.
1. Measure the Window Space
Taking accurate measurements is crucial for a successful installation. If possible, remove the old window before measuring to ensure precision. Measure down to the masonry or wood, not the current window box. If keeping the old window jamb, adjust measurements accordingly. Double-check all measurements for consistency before moving on.
2. Select the Right Glass Block Window
With measurements in hand, choose the right glass block window. Consider design preferences and privacy needs when selecting a style. Options range from clear blocks to frosted or patterned designs that offer varying levels of privacy. Remember that custom sizes may be necessary for nonstandard openings.
3. Remove the Old Window and Prep the Vacant Space
Carefully remove the old window and jamb if necessary. Wear gloves to protect your hands from broken glass. Use a pry bar for metal jambs or a saw for wooden ones. Clean the opening thoroughly, removing any leftover caulk or paint. To prevent mess, apply masking tape around the edge of the window space, avoiding areas where the new window will sit.
4. Mix and Apply a Bed of Mortar
Mix mortar according to manufacturer instructions until it reaches a cookie dough-like consistency. Apply about a half-inch layer of mortar to the base of the window space, smoothing it with a trowel. Place shims across the mortar bed, pressing them gently to secure their position.
5. Install Glass Block Window Panel
This step requires an assistant due to the weight of glass block windows. Lift the window into place from the outside, either tilting or sliding it in. Have someone inside steady the window to prevent it from falling inward.
6. Level and Mortar the Panel
Use a level to ensure the window is evenly placed and upright. Place shims snugly into the gap at the top to hold it in position. Recheck with the level, then fill gaps with mortar using a grout bag or trowel and tuck pointer. Work the mortar in thoroughly to eliminate air pockets, smoothing as you go. Allow about 30 minutes for the initial setting, then remove the shims and fill those holes with mortar.
7. Seal With Caulk
After 24 hours, apply a layer of glass block silicone caulk around the window, filling any gaps between the sill plate and glass. Clean up excess caulk immediately with soapy water to ensure a neat finish.
8. Clean Any Mortar or Caulk Residue
The final step involves cleaning up the installation. Use a damp sponge to remove any whitish mortar film from the glass blocks. To remove dried caulk, carefully scrape it away with a utility knife. This attention to detail will ensure a professional-looking result.
Glass Block Window Installation Cost
The cost of adding glass block windows can vary. Size is a major determinant, with larger projects naturally costing more. A prefabricated, 25-by-25-inch glass block window might cost between $60 and $300, while a 48-by-48-inch window could range from $155 to $840.
Style and finish also affect price, with clear blocks typically being less expensive than colored, frosted, or patterned options. For DIY installations, additional materials should be minimal, though tool purchases may increase the overall expense if not already owned.
Glass block windows often provide better insulation than standard pane windows, potentially leading to energy savings over time. This long-term benefit can offset the initial installation costs for many homeowners.
What Are The Benefits of Glass Block Windows?
Glass block windows offer several advantages that make them appealing to homeowners. They provide better insulation and privacy than regular windows and they deliver a special look.
Added Security and Privacy
One of the primary advantages of glass block windows is the enhanced security and privacy they deliver. The thick, sturdy construction of glass blocks makes them more resistant to break-ins compared to traditional windows. Also, options like frosted or patterned glass let light enter while obscuring the view from outside, making them ideal for bathrooms, basements, and street-facing windows.
Energy Savings
Glass block windows can contribute to improved energy efficiency in homes. Many modern glass block windows meet ENERGY STAR standards, offering better insulation than single-pane windows. Homeowners can also choose low emissivity (Low-E) glass blocks to reduce heat loss even more, creating more future savings.
Versatility
The versatility of glass block windows is another significant benefit. Available in prefabricated panels or as individual blocks for custom designs, they can fit into almost any space in a home. With a wide variety of designs, colors, and patterns available, homeowners can easily find options that complement their existing decor and architectural style.
Potential Drawbacks of Glass Block Windows
While glass block windows offer many benefits, homeowners should consider potential drawbacks before installation. Understanding these limitations can help them make an informed decision.
Maintenance Challenges
Glass block windows typically have more crevices and surfaces compared to traditional windows, which can make cleaning and maintenance more time-consuming. Regular upkeep is necessary to keep these windows looking their best and functioning properly over time.
Limited Ventilation
Unlike traditional windows, glass block windows generally cannot be opened. This lack of ventilation can be problematic in areas prone to high humidity, such as bathrooms or basements. It also means these windows can’t be used for emergency egress, which may be a consideration in some areas of the home.
Restricted Visibility
While glass block windows excel at letting light in while maintaining privacy, they don’t offer clear views of the outside. This can be advantageous for some spaces but may not be ideal for rooms where homeowners want to enjoy outdoor scenery.
DIY vs. Professional Glass Block Window Installation
Homeowners face the choice of tackling glass block window installation as a DIY project or hiring a professional. Each option has its pros and cons, and the best choice depends on individual circumstances.
DIY installation can be a cost-effective option for those with some home improvement experience. The project typically takes about a day, plus drying time for mortar and caulk. It allows for personal satisfaction and possible savings on labor costs.
However, professional installation might be preferable for challenging locations or if there’s existing damage around the window area. Professionals bring expertise and can often complete the job more quickly and efficiently.
As for costs, professional installation typically ranges from $700 to $1,000 per window, depending on location and local labor costs. While more expensive than DIY, professional installation often comes with warranties and ensures proper fitting and sealing.
Final Thoughts About Glass Block Window Installation
Glass block windows can be a fantastic addition to many homes, offering a unique blend of aesthetics, privacy, and functionality. Whether opting for DIY installation or professional services, homeowners can enjoy the benefits of these versatile windows with proper planning and execution.
While the installation process requires attention to detail and some effort, the results can significantly enhance a home’s appearance and energy efficiency. By weighing the pros and cons, considering the specific needs of their space, and following the steps outlined in this guide, homeowners can make informed decisions about incorporating glass block windows into their living spaces. With the right approach, these distinctive windows can provide years of enjoyment and practical benefits.
Frequently Asked Questions
Glass block windows can be washed just like regular windows. Exterior glass block windows can also be power washed for extra cleaning.
If properly maintained and installed, glass block windows can last 20 to 30 years on average. Regular maintenance can even extend their lifetime.
Glass block windows should be washed regularly. Cracks and chips in the mortar should also be resealed with caulk.
