Can my glass door be cut for a dog door? Often, yes: laminated glass can usually be cut on site, but toughened glass cannot.
If your door is laminated, the opening is cut into the panel you already have, in one visit. If the glass is toughened, the pet door goes into a new panel instead.
This guide covers how to tell which glass you have, whether laminated glass is safe to cut, why so many people are told they need a new panel, and when we will not cut.
The two ways to put a pet door into glass
- Cut your existing glass. The opening is cut into the panel while it stays in the frame. You keep the glass you already have.
- Replace the panel. A new toughened panel is made with the opening already cut, then fitted in place of the old one.
Which one you need comes down to two things: the type of glass in your door, and the size of your dog.
How do I know which glass I have?
Most toughened glass carries a small compliance stamp in one of the bottom corners, showing the manufacturer, the AS/NZS 2208 safety standard and the thickness. Laminated panels are not always stamped, but they often carry a label reading something like “Laminated Safety Glass 6.38mm”.
If you cannot find a mark, send us a photo of the corner of the glass and we will help identify it. Our technicians also carry laser identification tools, so we confirm the glass type on site rather than guessing.
Is it safe to cut laminated glass?
We hear this one a lot: “you cannot safely cut laminated glass”. That is not correct.
Laminated glass is made with a clear interlayer bonded between two sheets. If the panel cracks, the pieces generally stay stuck to the interlayer rather than falling out of the frame. That is also what makes laminated glass good for security.
It is not unbreakable. Laminated glass can still crack, usually from one of three things:
- Sudden impact: a ball kicked at the door, someone knocking into the glass, heavy pressure on the panel.
- Heat and long hours of direct sun, particularly on a west facing door in summer.
- Poor preparation of the cut edge. This is the one nobody mentions, and it comes down entirely to the installer.
Prepared properly, a cut laminated panel is sound. The laminated glass we cut on site includes 6.38mm, Hush laminated, 8.38mm, 10.38mm and 12.38mm.
Why are so many people told the panel has to be replaced?
Almost all companies will tell you the glass has to be replaced, or that it is not safe to cut. The honest answer is skill and experience.
A glazier is trained to replace glass. Glass can be cut lying flat on a factory bench, with the right table and the right conditions. Cutting the same glass standing upright in its frame, in someone’s home, with furniture either side and no second attempt, is a different skill, and not every installer or glazier is set up for it. Recommending a replacement is the safe choice for a business that cannot cut, and it is the more expensive option for you.
Cutting glass on site is what we have specialised in. We have cut over 30,000 panes since 2011.
When we will not cut your glass
Being able to cut glass also means knowing when not to. Even when a laminated panel can be cut, our technician checks:
- the size of your dog
- movement in the glass
- how much direct sunlight the panel takes
- whether the door is in a high impact area, such as a main thoroughfare or where children play
- whether the panel is oversized
If our technician judges a cut unsafe, we will not carry it out. We would rather lose the job than take your money for an installation likely to fail, and we will tell you what we would do instead, which is usually a new panel.
Toughened glass: a new panel, not a cut
There is one rule with toughened glass and it has no exceptions: it cannot be cut once it has been toughened. Trying to cut or drill it shatters the whole panel.
So if your door is toughened, the pet door arrives in a new panel. A new toughened panel is made to your glass size with the opening already cut, and then we remove the old glass and fit the new one. It costs more and takes longer, for the same reason: you are buying a complete new panel, and it has to be made before it can be fitted. There are also limits on how close the opening can sit to the edge of a toughened panel, which rules out some combinations of door and pet size.
In some bushfire prone areas, councils require toughened glass for certain openings. We check this from your photos and confirm it on the install day.
Large and extra large dogs
For large and extra large dogs we generally recommend a new toughened panel, whatever is in the door now. A big dog pushes a lot of weight through a pet door several times a day, and the bigger the dog, the bigger the opening and the more glass comes out of the panel. We would rather specify the glass for the job than cut a panel that was never meant to carry it. Our dog door sizes guide explains how to measure your dog.
Laminated or toughened: which is actually better?
Neither. They are built for different jobs.
Laminated glass
- A pet door can be cut into it on site
- If it cracks, the interlayer holds the glass together
- Hard to get through, because the broken glass stays bonded
- Generally better sound insulation
- Significantly reduces UV transmission
- Best suited to small and medium dogs
Toughened glass
- Cannot be cut, so a pet door means a new panel
- Much stronger than ordinary annealed glass against impact
- When it breaks, it shatters into many small blunt pieces
- Best suited to large and extra large dogs
“You can only have toughened glass” is not true
Where a door or side panel needs safety glass under the Australian standards, both Grade A toughened and Grade A laminated glass comply. AS/NZS 2208 sets what counts as a safety glazing material, and laminated glass meets it. Toughened is not the only compliant option.
“We have a new build with toughened glass, so it must be better”
Not necessarily. Toughened glass is common in new builds because it is what the builder specified for that application, not because it beats laminated across the board. If you already have good quality laminated glass, swapping it for toughened is not automatically an upgrade. We go by the glass you have, the dog you have and what the installation needs, then tell you which suits.
What about double glazed glass?
Double glazed units can take a pet door too, and we fit them. It is a different job from a single panel, because there are two panes and a sealed gap between them. Our guide can you put a dog door in double glazed glass? explains how it works.
Get your glass checked
Send us a photo of your door and the corner of the glass and we will tell you whether it can be cut. See our dog doors for sliding glass doors and cat doors for glass windows and sliding doors.
For a free quote, call 0421 575 229 or get a quote online.
