Tempered door glass cannot be cut, so a pet door is never cut into your existing panel. We order a new tempered unit, matched to your door, with the opening made at the factory, swap it into your sliding panel and fit the flap frame. The alternative is a panel insert in the track beside the slider, with no glass work. Measured on site, quoted before ordering.
What you get
- A new tempered glass unit, insulated or single-pane to match your door, with the pet door opening made before tempering
- Your existing sliding panel kept: the glass is swapped, the frame, rollers and lock stay
- The flap frame fitted and sealed through the glass, sized to your pet
- The panel-insert option explained and priced if it suits your door better
- Glass measured on site, with a written quote before anything is ordered
Why the pet door goes in new glass, not your old glass
The glass in a patio door is tempered safety glass. Tempering happens after the pane is cut to size, and once it is done the pane cannot be cut, drilled or notched; any attempt shatters it into a pile of small pieces. So nobody can cut a pet door into the glass that is in your door now.
What we do instead is order a new tempered unit for your sliding panel with the pet door opening already in it. The glass shop cuts the pane and the opening, then tempers it, so the finished pane is tempered all the way around the hole. On a double-pane door that is a new insulated glass unit; on an older single-pane aluminum door it is a single tempered pane.
Your panel frame, rollers and lock all stay. Only the glass changes. It is the same job as our glass replacement, with an opening in the right place.
How the job goes
- Measure. We pull the sliding panel, measure the glass opening and the old unit, note the glass type, thickness, tint, low-e coating and the bead, and talk through where the pet door should sit and which size.
- Quote. You get a written price for the glass unit and the pet door frame before we order. Nothing is ordered until you say yes.
- Order. The unit is made to size with the opening. We pass on the glass shop lead time when we quote.
- Install. On the install visit the old unit comes out, the new unit goes in with new glazing bead where needed, the pet door frame is fitted and sealed through the opening, and the panel is re-hung and adjusted.
The door stays in use between the two visits. Rollers and track get checked while the panel is apart, and the service call fee is waived when we do the glass.
Need a pet door in your slider this week?
Call or text with your address, how many doors and what the door is doing. You get a firm price before we come out.
Choosing the size
Pet door flaps run from cat size to large dog, and makers rate each size by pet weight and shoulder height rather than breed. The right opening is one your pet walks through without ducking or squeezing, with the top of the flap a little above the shoulder and the bottom low enough for an older animal to step over.
Bring your pet to the measuring visit, or send a photo with a tape against the shoulder. Going one size up for a puppy that is still growing is sensible; going two sizes up leaves a flap that lets in wind and does not seal.
Position matters as much as size. The opening usually goes low in the sliding panel, placed so the flap frame clears the handle and the fixed panel when the door is open, and we settle the exact spot with you at the measuring visit.
The other option: a panel insert in the track
A pet door panel insert is an aluminum-framed panel with a flap built in. It stands in the bottom track against the jamb, adjusts in height to fit the opening, and your sliding panel closes against it. No glass work, nothing cut, and it comes out to leave the door original, which renters like.
The trade-offs are real. The insert takes a few inches of the opening, it is less insulated than the glass, and the lock changes: your sliding panel now closes against the insert, so the hook in the handle set no longer reaches the keeper on the jamb. It needs a secondary lock, a pin lock or foot lock on the sliding panel, which we fit on the same visit; see lock and handle replacement.
Vacation rental owners often choose the insert so a guest with a dog can have it and the next guest cannot; see vacation rentals.
Glass unit or insert: which one for your door
Choose the glass unit when you own the home, you want the full opening and the full lock, and the door will have the pet door for years. It looks like it was always there and keeps the insulation and the original handle set working.
Choose the insert when you rent, you plan to sell, you want it out for part of the year, or you want the lower-cost route. Accept the narrower opening and the secondary lock.
Choose neither if the sliding panel frame is bent or rotted, or the glass is already fogged in both panels and the rollers are shot; then the money belongs in the door, not in a hole in it. Our repair or replace guide covers that call.
If your HOA has rules on exterior appearance, check before the measuring visit. A pet door in the glass is visible from outside; an insert is easier to remove for an inspection.
Pet doors in sliders across San Diego County
The call comes from dog households with a yard: the tracts of Poway and San Marcos, the older homes of La Mesa, and anywhere a slider opens onto a fenced patio. Vinyl Milgard and JELD-WEN panels take a new insulated unit easily; the 1970s aluminum doors get a single tempered pane with the opening, which is a simpler unit.
Ground-floor condos and rentals near the beach usually go with the insert plus a secondary lock, and our lock security guide explains why that lock matters on a door that opens to the patio.
Send a photo of the whole door from inside and one of your pet, with your city, and we will book the measuring visit.
Pet Door in a Sliding Glass Door: common questions
Can you cut a pet door into my existing sliding glass door?
No one can. Door glass is tempered safety glass, and tempered glass shatters if it is cut or drilled after tempering. The pet door goes into a new tempered unit made with the opening already in it, which we swap into your existing sliding panel. The frame, rollers and lock stay. The other route is a panel insert in the track with no glass work.
How much does a pet door in a sliding glass door cost?
We do not price it on the site, because the main cost is a made-to-order tempered glass unit, and that depends on your panel size, single or double pane, coatings and the pet door size. We measure on site and give you a written price before ordering. The insert option is quoted at the same visit so you can compare.
Does the pet door opening weaken the glass?
The opening is cut before the pane is tempered, so the finished pane is tempered all the way around the hole and is still safety glass. The pet door frame clamps through the opening and protects the edge. What you should not do is cut or drill the glass after the fact, which is why the unit is replaced rather than modified.
Will a pet door in the glass make my door less secure?
A small flap is not a way in for a person, but a large dog flap can be. Many flap kits come with a closing panel that slides in and locks the opening when you want it shut. Whichever size you choose, keep the main lock working and add a foot lock or pin lock on the sliding panel; we fit those on the same visit.
Can I get a pet door for a slider in a rental or if I plan to move?
Yes, with the panel insert. It stands in the track beside the sliding panel, needs no glass work and comes out to return the door to original. Get the landlord or HOA to agree in writing first. The insert changes how the door locks, so it goes in with a secondary lock on the sliding panel.
More answers on the FAQ page. Not sure what your door has? Send us a photo and we will tell you.
Where we do this
We cover all of San Diego County, usually within the week. Some of the places we work:
Related guides
- Repair or Replace Your Sliding Glass Door? An Honest Decision Guide – When a $250 to $400 repair brings a 40-year-old aluminum slider back, when the frame, glass or track means replacement, and typical costs for both.
- Sliding Glass Door Locks and Security in San Diego: What Works – Why a dropped door will not lock, mortise lock and keeper replacement, keyed vs non-keyed handles, secondary locks that work, and what renters can do.
Ready to get the door gliding again?
Call or text for a straight answer and a price before we come out. Mon to Sat 7am to 6pm.