Collection: Pet Door Size Guide NZ

Buying a cat or dog door for glass comes down to two things: the size of your pet and the glass in your door. Work through these four steps, then tell your glazier the model you've chosen.

Choose a pet door in 4 steps

1. Measure your pet standing up. Measure the width at the widest point and the body depth (top of the shoulders to the bottom of the chest). Add 25mm to each – both figures must fit inside the door's usable opening. If your pet is close to a limit, size up.
2. Pick the door size. The cut-out is the round hole your glazier makes in the glass.

   Door	Cut-out	Usable opening (W × H)	Suits
   Catwalk original cat door	245mm	165 × 180mm	Cats up to about 7kg
   Catwalk Maxi	267mm	187 × 190mm	All cats, including 7–10kg breeds like Maine Coons, and small dogs up to about 300mm at the shoulder
   Dogwalk Intermediate	320mm	216 × 237mm	Small to medium dogs up to about 380mm at the shoulder
   Dogwalk dog door	385mm	270 × 300mm	Medium to semi-large dogs up to about 450–500mm at the shoulder, such as Beagles, Border Collies, Spaniels and Blue Heelers

3. Check your glass thickness. Each frame fits a range of glass thicknesses (see the full comparison table below the products). Your glazier can confirm the thickness of your glass.
4. Single or double glazing? Slim Line frames suit single glazing and most sliding doors. Dual Glaze frames are deeper and suit double-glazed units as well as single glazing. Within each size, both frames have the same cut-out and the same usable opening.

Fit the door so the bottom of the opening sits level with the bottom of your pet's chest when standing.

Full comparison: Pet-Tek glass pet doors

C = clear frame, W = white frame. All specifications are from Pet-Tek.

The multi-magnetic cat door (G-MCDW, and W-MCDW for wood) opens only for cats wearing a Catwalk collar magnet. Its usable opening is 155 × 157mm, and Pet-Tek recommends it for cats 9 months and older.

Not fitting into glass?

For timber, PVC or metal door panels, wood-fitting doors go in DIY with the supplied cutting template, a drill and a jigsaw – no glazier needed.

• W-SDDW Dogwalk wood-fitting small dog door – panels 11–30mm thick; usable opening 180 × 227mm, for small dogs up to about 360mm at the shoulder and large cats.
• W-MCDW Catwalk wood-fitting multi-magnetic cat door – panels 11–52mm thick (wood, steel or PVC).

Fitting a door into glass: what to know before you order

• You need a glazier. Don't try to cut glass yourself – incorrect cutting can crack or shatter it.
• Toughened glass must be cut before it's toughened. Toughened (safety) glass and sealed double-glazed units can't be cut on site. The glazier orders a replacement panel with the round hole pre-cut at manufacture, fits it into your door or window, then installs the pet door.
• Give your glazier the model and cut-out size (245, 267, 320 or 385mm) and confirm your glass thickness before you order.
• Pet-Tek says most installations take under an hour once the new panel arrives.

Installation videos from Pet-Tek

Glass-fitting pet doors

Wood-fitting pet doors

Common questions

What's the difference between Slim Line and Dual Glaze?
Only the frame depth. Within the same size, both have the same cut-out and usable opening. Slim Line has a lower-profile frame for single glazing and sliding doors; Dual Glaze has a deeper frame that suits double-glazed units and thicker glass.

Can a pet door go into my existing ranch slider?
Only by replacing the glass panel. Existing toughened or double-glazed glass can't be cut, so your glazier fits a new panel with the hole pre-cut.

Which door suits a Maine Coon or another big cat?
The Catwalk Maxi (267mm cut-out). The original cat door suits cats up to about 7kg.

Which replacement flap do I need?
Match the flap to your door's model code (see the Replacement flap column above). Browse all Pet-Tek Catwalk and Dogwalk doors and flaps.

Comparing door types, microchip flaps or renting rules? See the Cat Doors NZ guide on the PetMall Knowledge Hub.