What to check on flat glass before purchase
Jun 05, 2026
The flat glass, also named raw glass or float glass, the stuff before any process. It used everywhere like windows, tabletops, partitions, which role as basics: Light in, weather out, some insulation and noise control.
Thickness:
The national standard GB11614 lists nominal thickness 2mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, 19mm, 22mm, 25mm. Each has deviation allowance.
But here's what some shops do - they push 4.6mm or 4.8mm as "close enough" to 5mm. Don't fall for it. Non-standard glass gives you worse insulation, weaker safety, and real risk of falling panes down the road. Measure it or ask for the spec sheet.
Second: look at it
Three quick checks:
Clarity - better transparency means better look and more light.
Surface - run your hand or eyes over it. Obvious scratches? No.
Inside - bubbles or spots beyond standard limits? They hurt both optics and looks.
