Dog Door Installation
A dog door installed correctly is not a gap in your home's envelope — it is a properly sealed, permanently fitted access point that closes, latches, and weather-seals when not in use, exactly as the surrounding door does. The distinction matters on Long Island, where winters bring sustained cold from the north and east, where humidity off the Sound and the Atlantic puts constant pressure on any unsealed opening, and where a pet door that does not seal correctly is effectively a draft source.
Prestige Window Works installs dog doors throughout Nassau and Suffolk County using through-glass installation methods that allow the surrounding door to function normally — closing, latching, and locking with the pet door fitted into the glass panel rather than cut into the door frame or hung on a makeshift bracket. The result is a permanent, weather-tight installation that does not compromise the door's operation or its appearance, and that suits the specific glass panel type in your door.
We serve homeowners from our Manhasset office across Nassau County and our Hauppauge office across Suffolk County.
From Woodbury and Syosset in Nassau to Dix Hills and Melville in Suffolk, call 516-908-8005 or fill out the form online for a free on-site estimate.
From Woodbury and Syosset in Nassau to Dix Hills and Melville in Suffolk, call 516-908-8005 or fill out the form online for a free on-site estimate.
When a Pet Door Makes Sense
Dog door installations come to us through a specific set of situations — each with its own correct approach. Long Island's particular combination of backyard-oriented living, rear deck construction, and active outdoor dog culture makes these calls consistent across Nassau and Suffolk County year-round.
French Door Panels
A French door opening onto a rear deck is the most common dog door installation we complete on Long Island. Because French doors swing on both panels, there is no fixed panel suitable for a frame-mounted pet insert — the correct solution is a through-glass installation in the lower section of one panel, producing a permanent sealed opening while the door continues to function normally. Our portfolio includes a completed French door dog door project in Oakdale, NY. See also our full French door repair service for any related French door work on the same property.
Sliding Glass Doors
Sliding glass doors opening to rear patios and decks are the second most common installation type on Long Island. Two installation methods apply here: through-glass installation into the fixed glass panel if accessible, or a purpose-built panel insert that fits into the track alongside the sliding panel and allows the door to close and lock normally.
We assess which method is correct for your specific sliding door configuration and opening dimensions on-site.
We assess which method is correct for your specific sliding door configuration and opening dimensions on-site.
Makeshift Setup Replacement
The homeowner has been using a temporary insert — a pre-packaged wedge unit propped in an open door panel — as a stopgap that was never intended to be permanent. This is one of the most common situations we encounter: a workable temporary fix that has become the permanent situation by default, leaving the door unable to close whenever the dog needs access. Through-glass installation eliminates the makeshift setup entirely, restores the door's normal function, and provides a sealed permanent solution in a single visit.
New Deck or Patio Access
A new deck or patio has been built and the homeowner wants direct dog access from the main living space without leaving a door panel open or adding a full door opening. Dog door installation into the existing adjacent glass door panel is the correct approach — using glass cutting techniques to prepare the opening and fitting a sealed pet door housing sized for the dog. Related to our storm door installation service for properties adding a new storm door in the same project.
Single Glass Panel Doors
A single-panel glass door — a full-lite entry door, a glazed utility door, or a single-panel back door — needs a pet door fitted into its lower glass section.
Through-glass installation into a single panel is the most straightforward approach and produces the cleanest result, with the pet door housing seated flush with both interior and exterior glass faces and sealed on all edges.
Through-glass installation into a single panel is the most straightforward approach and produces the cleanest result, with the pet door housing seated flush with both interior and exterior glass faces and sealed on all edges.
Multiple Dog Households
The household has multiple dogs of different sizes and needs a pet door wide enough for the largest dog while maintaining an adequate weather seal. We discuss opening dimensions and select the correct pet door unit before cutting any glass — a door that is slightly oversized for the largest dog is preferable to one that causes discomfort on entry, and we size the installation accordingly at the estimate stage.
Cat and Multi-Pet Access
A household with both dogs and cats needs a pet door sized to allow the dog access while preventing the cat from exiting unsupervised — or vice versa. Selective-access pet door units with microchip or magnetic collar recognition provide controlled access by animal. We install and fit selective-access units in glass panels for households where access control between pets is a requirement.
Installation Methods — What We Use and Why
Through-Glass Installation
The method we use for French doors, single-panel glass doors, and fixed panels in sliding glass door systems. We measure the opening precisely, cut the glass using specialist equipment, seat the pet door housing with weatherproof sealant on all edges, and test the flap seal before finishing. The cut must match the housing exactly — undersized prevents correct seating, oversized leaves unsealed gaps. Same controlled technique as our glass cutting service.
Panel Insert for Sliding Doors
Used where the existing glass cannot be cut — tempered panels or limited fixed-panel access. A full-height insert fits into the sliding door track alongside the glass panel, carrying the pet door in its lower section. The sliding panel closes against it normally and the door locks as before. Standard off-the-shelf inserts frequently do not fit Long Island sliding doors correctly — we measure and specify on-site. Andersen and JELD-WEN systems have specific track profiles that require correctly-matched inserts.
Sizing and Flap Selection
We confirm the correct opening dimensions for your dog before any glass is cut — shoulder width plus margin for comfort, sized for the largest dog in multi-dog households. For selective-access units, we confirm microchip or collar compatibility before installation. On Long Island, flap material matters: standard vinyl flaps stiffen in sustained below-freezing temperatures. For properties in Jericho, Nesconset, and other inland communities where January and February lows are sustained, we discuss double-flap or insulated flap options.
The method we use for French doors, single-panel glass doors, and fixed panels in sliding glass door systems. We measure the opening precisely, cut the glass using specialist equipment, seat the pet door housing with weatherproof sealant on all edges, and test the flap seal before finishing. The cut must match the housing exactly — undersized prevents correct seating, oversized leaves unsealed gaps. Same controlled technique as our glass cutting service.
Panel Insert for Sliding Doors
Used where the existing glass cannot be cut — tempered panels or limited fixed-panel access. A full-height insert fits into the sliding door track alongside the glass panel, carrying the pet door in its lower section. The sliding panel closes against it normally and the door locks as before. Standard off-the-shelf inserts frequently do not fit Long Island sliding doors correctly — we measure and specify on-site. Andersen and JELD-WEN systems have specific track profiles that require correctly-matched inserts.
Sizing and Flap Selection
We confirm the correct opening dimensions for your dog before any glass is cut — shoulder width plus margin for comfort, sized for the largest dog in multi-dog households. For selective-access units, we confirm microchip or collar compatibility before installation. On Long Island, flap material matters: standard vinyl flaps stiffen in sustained below-freezing temperatures. For properties in Jericho, Nesconset, and other inland communities where January and February lows are sustained, we discuss double-flap or insulated flap options.
Why the Installation Method Matters on Long Island
Dog door installation is not a single service — the correct method depends entirely on the type of door being fitted, and getting it wrong produces an installation that either compromises the door's function or fails to seal within a season. Long Island's climate amplifies every gap left by a poorly executed installation.
The most common approach on Long Island residential properties is through-glass installation into an existing door panel — either a French door, a sliding glass door, or a single-panel glass door opening onto a rear deck or patio. Through-glass installation cuts an opening in the lower section of the glass panel and fits a permanently sealed pet door housing that fills that opening completely — the door continues to close, latch, and weather-seal as it did before.
The alternative — a panel insert in a sliding glass door track, a wall-mount below the door, or a temporary wedge insert in an open door panel — all involve compromises that are particularly costly in Long Island's climate. We assess your specific door type and opening conditions at the estimate visit and recommend the installation method that produces the correct, permanent result for your situation.
The most common approach on Long Island residential properties is through-glass installation into an existing door panel — either a French door, a sliding glass door, or a single-panel glass door opening onto a rear deck or patio. Through-glass installation cuts an opening in the lower section of the glass panel and fits a permanently sealed pet door housing that fills that opening completely — the door continues to close, latch, and weather-seal as it did before.
The alternative — a panel insert in a sliding glass door track, a wall-mount below the door, or a temporary wedge insert in an open door panel — all involve compromises that are particularly costly in Long Island's climate. We assess your specific door type and opening conditions at the estimate visit and recommend the installation method that produces the correct, permanent result for your situation.
Dog Door Installation Across Long Island, NY
We install dog doors throughout Nassau and Suffolk County from our Manhasset and Hauppauge offices.
Our Manhasset office covers Nassau County — including Woodbury, Syosset, Jericho, Massapequa, Garden City, and Great Neck.
Our Hauppauge office covers Suffolk County — including Dix Hills, Melville, Nesconset, East Setauket, Huntington, and Smithtown.
For homeowners searching for dog door installation near me on Long Island, call 516-908-8005 to confirm scheduling. We book within 1–3 business days throughout Nassau and Suffolk County, with Saturday and Sunday availability.
Our Manhasset office covers Nassau County — including Woodbury, Syosset, Jericho, Massapequa, Garden City, and Great Neck.
Our Hauppauge office covers Suffolk County — including Dix Hills, Melville, Nesconset, East Setauket, Huntington, and Smithtown.
For homeowners searching for dog door installation near me on Long Island, call 516-908-8005 to confirm scheduling. We book within 1–3 business days throughout Nassau and Suffolk County, with Saturday and Sunday availability.
THE MOST POPULAR QUESTIONS
Can a dog door be installed in a French door without replacing the door?
Yes — and this is the most common installation we complete on Long Island. Through-glass installation cuts the pet door opening into the lower glass panel of the French door only. The door frame, hardware, latching system, and weatherstrip are not touched. The door continues to close, latch, and lock normally after installation. See our completed French door dog door project in Oakdale, NY for a before and after example.
What is the difference between through-glass installation and a panel insert?
Through-glass installation cuts an opening directly into an existing glass panel and fits a permanently sealed pet door housing into that opening — the door continues to function normally. A panel insert is a separate unit that fills the full height of a sliding door track opening and carries the pet door in its lower section — the sliding panel closes against it and the door locks normally. Through-glass is generally the cleaner permanent solution; panel inserts are used where the existing glass cannot be cut, such as on tempered panels that were installed after the glass was heat-treated.
How do I know what size dog door I need?
Measure your dog's shoulder width and add approximately 2 inches for the opening width. Measure shoulder height from the floor and add 2 inches for the flap height. For multiple dogs, size for the largest. We confirm sizing at the estimate visit before any glass is cut — getting the size right before installation is significantly more straightforward than correcting it after.
Will the dog door affect the insulation of my home during Long Island winters?
A correctly installed and sealed through-glass pet door has significantly better thermal performance than leaving a door panel open or partially propped — which is the situation most Long Island homeowners are working with before installation. Double-flap and insulated flap units improve cold-weather performance further and are worth discussing for properties where the pet door will be in regular use through January and February. We discuss flap options at the estimate visit.
How much does dog door installation cost on Long Island?
Cost depends on the installation method, the pet door unit selected, and any glass-related work required. Through-glass installation into an existing panel has different cost factors from a panel insert fitted to a sliding door track. We provide a written quote at the free estimate visit before any work begins. Call 516-908-8005 to schedule.
What other services do you offer that are related to dog door installation?
Dog door work connects to several of our other services. Our glass cutting service covers the precision glass cutting that through-glass installation requires. Our glass replacement service addresses any other glass work needed on the same door. Our door adjustment service covers any fitting or sealing work on the surrounding door frame. And our storm door installation service is relevant for homeowners adding a storm door at the same entry where the pet door is being fitted.