How to: Add Recycled Glass Aggregates to Concrete Countertops and More
If you’re looking for a way to make your next concrete countertop stand out, look no farther than recycled glass aggregates. Glass adds texture, color and design elements to both indoor and outdoor countertops. Glass aggregates come in many colors and four sizes from fines to pieces as large as 70mm. If you’re not sure how to use glass aggregates in your next concrete project, read on!
Do-It-Yourself: Adding Recycled Glass Aggregates to a Concrete Countertop
Step 1. – Aggregate Size Matters. Smaller aggregates are used differently from larger sized glass. Allow for at least 1/16” between size 1 and 2 glass to ensure good adherence, especially when later polishing to reveal. The larger pieces, Size 3 and 4, should be ½” to ¾” apart. Use different glass sizes and colors together to create your own unique look. Mix Size 0, fines and light bulb glass directly into the countertop mix for a “sparkly” appearance after polishing.
Idea:
Countertop lighting is increasingly an increasingly popular feature particularly for outdoor entertainment areas. Consider using the size 3 and 4 glass as “lit glass” elements on a bar or kitchen top.
Step 2. – How Much Aggregate Do I Need? You’ll need 1lb. of glass aggregates per 1.5 sq. ft. Size 1 requires ¼” dispersion and Size 2 1/2”. In other words, you’d need 5 lbs. for a 7.5 sq. ft. If including light bulb glass, fines and/or size 0 aggregates to the countertop mix, add 15 lbs. per 50lb. box of countertop mix. Larger pieces can be pressed into place as desired.
Step 3. – Inspect, Wash and Allow to Dry. Though great care is given to sizing and sorting glass aggregates, they are reclaimed from municipal recycling programs and industrial waste glass. Check your glass carefully for paper, metal and undesired glass colors that might have been unintentionally mixed in. Wash and allow to dry completely before use.
Step 4. – Getting Started. If you’re pouring a pre-cast countertop, trowel a 1/8” of mix into the form for Size 1, ¼” for Size 2 and up to ½” for the larger glass aggregate sizes. For a poured-in-place countertop, pour the countertop mix into the form according to the instructions, trowel smooth, press glass into place the appropriate distance apart for the glass size and trowel again. Once the countertop has cured for 21 days and is out of the forms, polish to reveal with a 50-grit and continue polishing up to a 200-grit level. If desired, apply acid stain at this point and seal with the Penetrating Lithium Hardener Sealer before polishing to the 1500-3000 grit level. If sealing with a polyurethane or epoxy, polish up to 800-grit level and apply. Though countertops can be dry sanded, wet sanding is by far the better option because the polishing pads last longer and create a smoother, more streak-free finish.
Questions?
Our technicians are always available to help. Call us at 877-255-2656 or email at info@directcolors.com.
We used recycled glass on a “test” countertop. We placed the glass in the mold and then poured the cemento on top. Started grinding with 50 grit and we cannot find any of the glass or aggregate we added. We suspect it all shifted to the edges when we sifted side-to-side to remove air bubbles. How do we get the aggregate to stay in place?
Thanks for your comment. If you are making a pre-cast countertop, it’s important to trowel down mix into the form first and press the aggregate into the mix. This will hold the aggregate in place and allow you to later polish to reveal. For more information on using glass aggregate in a countertop, read our how-to guide on making concrete countertops. Good luck with your project.
How do you get the glass on the edges of the countertop?
To add glass aggregates to the edges of a countertop the countertop mix will need to sprayed into the form from a hopper gun. Spray the mix along the face and edges to a depth of at least 3/16th in. and press the glass into place. Please see our countertop video to see how to spray countertop mix. Thank you and please let us know if you have any further questions.
Out of curiosity I love the blue and white sample top that is in one of your photos. How did you get this effect. What is the white aggregate?
Thanks for your message. The white aggregate is called mode on our website and can be purchased in a couple of size variations. The trick to getting this look is mixing the aggregate throughout which depending on the size of the project might be a little pricey but it certainly looks great. If you decide to go forward with the countertop, give our countertop expert, Frank, a call on W-T-F at 877-255-2656. He just walked a customer through this process last week and would be happy to assist. Thanks again.
Can the glass aggregate be added into the concrete mix before pouring? I’m wanting to make sure the edges of my cast in place countertops will have glass showing after polishing. If so what would be the ratio you recommend?
Thanks for your message. Please review the section in our how to guide for concrete countertops that pertains to the use of glass in pre-cast countertops. All the details for glass placement and polishing are there. As for the dispersion rate for glass aggregates, add 3/4 lb. per square foot for a 1/2 in. dispersion for Size 2 and 3/8 in. for Size 1. Please let us know if you have any further questions and good luck with your project.