Updated 2026 | By Glass Block HQ
If you have never had glass block installed, you probably have questions about the process. How long does it take? What happens to old windows? Will it be messy? Here is exactly what happens at each step, plus the red flags that separate a quality installation from one that will cause problems.
Before Install Day — What a Good Contractor Confirms
Opening measurements for each window. Pattern choice and privacy level. Whether ventilation is needed and which type. Warning signs like crumbling sills, rusted frames, or evidence of water intrusion. A good contractor identifies problems before installation day, not during.
Step 1 — Free Measurement and Consultation
We visit your home, walk through every window you are considering, and take precise measurements. We discuss your priorities — security, ventilation, privacy, aesthetics — and recommend the best pattern and vent configuration for each window.
You receive a written quote that covers materials, installation, removal, cleanup, and warranty. Our quotes are designed to be all-inclusive; if we uncover hidden conditions during the work, we walk you through options before proceeding.
Step 2 — Scheduling
Most homeowners have installation scheduled within a few weeks of placing their order. Spring and early summer are busiest, so booking early gets the fastest scheduling.
Step 3 — Installation Day
Protect the work area. Drop cloths go down before any work starts. Surrounding finishes are protected.
Remove old window assembly. We extract the old frame, remove deteriorated caulk or mortar, clean the opening down to solid substrate, and haul away all old materials.
Prep the opening. This is where quality shows up — and where less careful installers cut corners. We address loose or crumbling material, ensure the surfaces are clean and stable, and confirm the panel will sit correctly and seal properly. Poor opening prep is the most common reason glass block installations develop problems. It is also the most common shortcut. For more on why installation method matters so much, see our mortar vs silicone breakdown.
Set the glass block panel. The custom-fabricated panel is leveled and plumbed precisely, then mortared to the surrounding wall structure.
Seal the perimeter. Perimeter sealing is what prevents drafts and moisture intrusion. Another area where less careful installations often fall short.
Clean up. Drop cloths come up, debris gets hauled away, your space looks better than when we arrived.
How Long Does It Take?
Single basement window: 1 to 2 hours. Full basement (4 to 8 windows): typically one day (see our full basement guide). Bathroom window: 1 to 2 hours. Garage windows: 2 to 3 hours per window. Shower walls: 1 to 2 days plus cure time (see our shower wall design guide).
Most residential projects complete in a single visit.
After Installation
After about 24 hours, the installation has initial set; vents (if included) can typically be used normally. Full mortar cure takes about 7 days, consistent with Portland Cement Association guidelines. Avoid cleaning products on mortar joints during the first week.
Ongoing maintenance is typically minimal — occasionally check perimeter sealant and keep surfaces clean.
Red Flags of a Bad Installation
The opening was not prepped — installer just caulked the panel in without addressing the substrate. The panel does not feel solid when you press on it. Vents feel flimsy or poorly sealed. Visible gaps or messy perimeter finishing. No written warranty provided.
If you see any of these in a completed job or in a quote that seems unusually cheap, it is a sign of shortcuts that will likely cause problems.
Your Workmanship Warranty
Every GlassBlockHQ installation comes with a lifetime workmanship warranty. Ask us about the details during your consultation.
Ready to Get Started?
Cleveland: (216) 941-5470 | Columbus: (614) 852-4608 | Cincinnati: (513) 776-1805
Get your free quote at /get-a-quote/
Frequently Asked Questions
Do I need to be home during installation?
An adult should be available at the start for access and any quick decisions. After that, you are welcome to step out—our crews work independently and professionally.
Will it be messy?
No. We protect your home with drop cloths and clean up completely before leaving. Your space will look better when we leave than when we arrived.
Do I need to prepare anything?
Just clear about 3 to 4 feet around each window being replaced. That is all we need.
Can you install in winter?
Yes. We use cold-weather mortar additives and install year-round across Ohio. We schedule around extreme weather, but standard Ohio winter conditions do not stop us.
What about non-standard window sizes?
Every panel is custom-fabricated to your exact opening dimensions. Non-standard sizes are literally our standard—we do this all day, every day.