FURNISHINGS : The Many Breeds of Pet Doors

Rover wants out in a big way, which means you trudging over to the door and freeing him for the 45th time that day. There are scratched doors and shredded furniture if you elect to sleep at night and ignore your dog’s desires to get out.

A doggy door can be your route to freedom, says Diana Bradfield of Petdoors USA in Bradenton, Fla.

“We get people calling us saying, help, help,” she says.

Doggy doors come in many shapes and forms.

Electronic gadgetry can take your pet portal to a new plane. Electronic pet passageways enable you to limit entry to your animals, keeping out stray cats or dogs hot on Fluffy’s tail. The Cat Mate electromagnetic cat flap ($89.95 plus shipping from Patio Pacific) uses a magnet on the cat’s collar to trip a battery-operated sensor in the flap frame and open the flap silently. The animal must be right at the door before the sensor will unlock it.

Petway makes a powered pet door that Fluffy opens by stepping on a foot pedal. Because it’s on tracks, the door can’t be lifted by the wind.

Then there’s the Open Sesame. This wall-mounted electronic door is the state of the art in doggy doors. The owner can preset the length of time the panel remains retracted; it stops if it hits something. The panel locks automatically when it closes, and it can be tied into a home security system. Usable by cats and dogs that weigh up to 110 pounds, it costs $450, making it the most expensive of doggy doors.

But back to the basics.

Doggy doors have been designed for installation in solid doors, as panels butting up to sliding glass doors and as private entrances cut through walls. They can be installed in French doors, in sash windows or in windows that slide sideways. “Anyplace you can put a hole in your house, you can put in a pet door,” says Alan Lethers of Patio Pacific in San Pedro, a firm specializing in animal entries.

Most doggy doors are available with locking systems and tough frames to resist entry.

“Pet owners are looking for a weather-tight fit, a flap suited to the pet and a sturdy security cover,” says Paul Reynolds of the California Dog House & Dog Supplies in Orange.

Reynolds’ customers favor putting their pet passageways in wood doors, but also popular are the panels that fit into standard frames for sliding glass doors. The Pet-Eze Custom Deluxe ($170 to $230) panel offers tempered safety glass, a reversible lock and weatherstripping. You can keep the sliding glass door closed and locked while giving Rover 24-hour access. No glass cutting or door-frame alteration is needed.

Pet door firms usually offer installation of their products, although many units for sliding glass doors can be installed by the owner with about an hour of work.

The Instapanel ($140 to $175) by Pet-Eze can be installed especially quickly, but it’s not for larger dogs, has no lock, steel security cover or water-seal adapters. If you want to lock the door, you remove the panel.

To determine an adequate door size for your dog, Lethers recommends opening your sliding door to flap width, holding two boards to simulate the top of the flap and the rise (the distance from the floor to the bottom of the flap) and encouraging your pet to take a trip or two through the opening.

You may prefer a narrow opening to minimize drafts or to discourage entry by larger critters. Or you may want your animal to have plenty of room to make his entrance or exit, in which case you would choose a larger door.

Hale Security Pet Doors makes an especially wide range of doors ($140 to $300) for small pets through “tall large plus” and on up to “giant”--adequate even if your pet’s a porker.

At the same time you are considering where the pet door will go, also evaluate the type of flap or door you want on the pet entry. Choose one that fits securely enough to keep out wind and water, yet is flexible enough to allow easy entry. Most of the flaps are flexible rubber or vinyl, Reynolds says. Other options include plastic hinged flaps and sliding panels.

The same door can work if you have a dog and a cat, but it depends on the size of the dog. If you have both, position the door low enough for the cat (usually not more than a five-inch rise), but high enough so the dog doesn’t have to stoop to get through, Reynolds says.

If you have a great Dane and an average-size cat, get a larger door with a thinner flap so both animals can use the door. A flap that’s too heavy or rigid will be too much for the cat.

Also, consider the security of the pet door itself. A door large enough for a big dog can provide easy entry for a burglar. Most doors have some sort of cover that can be locked in place to prevent an unwanted entry if you are not home.

Cheaper models have lightweight plates that may be inadequate for serious security. Higher-price models use tougher plates. Pet Eze uses a steel cover, while Hale uses Lexan that’s three-sixteenths of an inch thick.

Once you have your pet passage in place, is your beast going to use it? Most animals adapt quite readily, Lethers says.

“The major problem is (caused by) the owner who tries to shove his pet through the pet door,” he says. Train your pet by using positive behavior reinforcement techniques. Prop up the flap so that the animal can see through the gateway, and dangle a goody on the other side. (Some people use a clear flap, enabling the animal to see what’s on the other side.)

As the pet gets the hang of going through, lower the flap a bit more.