I have spent years fitting pet doors around Christchurch, mostly in older timber homes, aluminium sliders, ranch doors, and double glazed panels that owners were nervous about touching. I started as a glazing installer, then found myself doing more pet access work after people realised a rushed cut in the wrong panel can turn into an expensive repair. I still keep a small notebook in the van with measurements, glass types, and the odd reminder about which cats refuse to use flap doors on the first day.
Why I Treat Every Door Like Its Own Small Job
I never arrive assuming a pet door is a simple square cut and a few screws. In Christchurch, I see homes from the 1950s sitting beside newer townhouses with thermally broken aluminium joinery, and the approach changes from one to the next. A laundry door in a weatherboard home might take one method, while a double glazed slider in a newer build needs a different plan altogether.
The first thing I check is the material, the glass, and the direction the weather hits. A southerly rain line across a back door tells me more than a brochure ever will. I have seen a cheap flap rattle all night in a coastal breeze because nobody thought about wind before fitting it.
Small details matter. I measure from the pet’s belly height rather than guessing from the owner’s knee or the bottom rail of the door. One customer last winter had a small terrier and a large older cat sharing the same access point, so I had to set the flap low enough for the cat without making the dog crouch awkwardly every time.
Glass, Timber, Aluminium, and the Choices That Cost People Later
The biggest mistake I see is someone trying to cut existing toughened glass. That does not work because toughened glass is made to hold its strength after processing, and once it is cut or drilled it usually breaks into small pieces. For glass doors, I normally arrange a new pane or double glazed unit with the pet door hole made before the glass is toughened or sealed.
I have had homeowners ask me why the price changes so much between a timber panel and a double glazed unit. The short answer is that a timber door can often be cut on site, while glass has to be measured, ordered, made, and fitted properly. For a client comparing local options, I might point them toward a service page like pet door installation christchurch so they can see how glass and joinery work is usually handled by people who deal with it every week.
Aluminium doors sit somewhere in the middle. Some have enough flat panel area to take a pet door cleanly, while others have narrow rails, internal bracing, or powder coated profiles that are easy to mark if you rush. I use masking, pilot holes, and a steady hand because a slip on black aluminium shows up from three metres away.
Timber is more forgiving, but it still deserves care. Older Christchurch doors can have layers of paint, soft spots near the bottom, or swelling from years of damp winters. If I find rot near the cut area, I stop and talk it through because putting a new flap into weak timber just hides a problem for a few months.
The Part Owners Usually Underestimate
Most people focus on the flap size, but I spend nearly as much time thinking about position. Too high, and a small cat hesitates. Too low, and the door frame can lose strength or let water sit where it should not.
I also look at what sits outside the door. A pet door that opens straight onto a step can be fine for a young dog, but it may be awkward for an older cat or a dachshund with a long back. I once fitted a door for a family near a raised deck where the outside drop was only a small one, yet their elderly cat treated it like a cliff for the first week.
Security comes up often, especially with larger dog doors. I do not pretend any flap is the same as a locked solid door, because it is still an opening. What I can do is help choose a size that suits the animal without creating a silly gap, and I can suggest a locking panel for night or when the house is empty.
Microchip doors have become common for cats around Christchurch suburbs where several neighbourhood pets wander through the same section. They are useful, but they still need the right installation height and a weatherproof fit. I tell people to keep the manual in the kitchen drawer because pairing a second cat months later is much easier when the instructions have not disappeared.
How I Keep the Install Tidy and Weather Tight
A neat install starts before any cutting. I lay down a dust sheet, mark twice, and check the swing path of the flap with the pet’s likely body angle in mind. On timber doors, I drill the corners first and cut slowly so the outer face does not splinter into an ugly edge.
For glass jobs, the tidy part is mostly in the measuring. I record the unit thickness, spacer colour, glass type, overall size, and the exact hole position. A few millimetres can matter, especially on a double glazed panel where the pet door needs to sit level and clear of the frame.
Sealing is where rushed work often shows itself. I use the gasket supplied with the pet door if it is decent, then add suitable sealant where the surface needs help. I do not like overdoing sealant because a big messy bead can trap dirt and make the whole job look like a repair instead of a clean install.
After fitting, I test the flap several times from both sides. I listen for rubbing, check the lock, and look for daylight around the frame. If I can see a gap from inside at midday, that gap will feel much worse during a cold July evening.
What I Tell Christchurch Pet Owners Before I Leave
I always tell owners to give the animal time. Some pets use the new door within 10 minutes, while others need a few days of treats, patience, and a flap taped open for short practice sessions. Pushing a nervous cat through usually makes the job harder.
I also explain that exterior doors get more punishment than people expect. Rain, dust, UV, and repeated use by a muddy dog can loosen cheap parts over time. A quick wipe of the flap and a check of the screws every few months keeps most issues from turning into repairs.
For renters, I suggest getting written permission before any install. It sounds obvious, but I have been called to remove a pet door from a rental door after a tenancy ended, and the owner was not happy about the original cut. In some cases, fitting into a removable panel or arranging a replacement glass unit can make the exit plan cleaner.
My own preference is to match the pet door to the house rather than forcing the cheapest unit into the easiest spot. A small cat door in a sheltered laundry door is a different job from a medium dog flap in a street-facing glass panel. If the door looks tidy, closes properly, and the pet actually uses it, I count that as the right result.
A good pet door should feel like it was always meant to be there. I have walked away from jobs where the owner barely noticed the fitting after a week, except that they no longer had to get up at 5 in the morning for the cat. That is usually the sign I did the work properly.