Rabbit-proofing is essential to ensure the safety of your bunny companions. Rabbits are natural chewers, and many of the items they are most drawn to --furnature, baseboards, power cables-- can hold severe and painful consequences if not properly rabbit-proofed and stored out of reach. Remember, even in a well bunny-proofed home, you may find your rabbit tempted by things other bunnies would have no interest in. Be diligent in watching your bunny's behaviors and habits, and take steps to remedy any hazards right away.
Barriers: Unsafe areas may need to be blocked off entirely. Kitchens, bathrooms, heat/AC vents, curtains, certain pieces of furniture, and tight spaces are some of the dangerous places and objects on which a rabbit can be hurt or become trapped. Rabbits are very smart and can take down or jump over flimsy or makeshift barriers in seconds. If an entire puppy pen is too large to block off an area, “NIC” cube panels can be connected with zip ties (with the “tails” trimmed off) and be used to form a short fence to block off danger.
Baby gates can be used to block off an area, but be sure to choose one that a rabbit cannot fit any part of her body though (head, legs, etc). You can put tall sheets of cardboard at the top to make it appear taller, if needed. Rabbits respect visual barriers.
Cords/cables/wires: Rabbits are drawn to electrical cords. If they're accessible, your rabbit will find them and find them quickly! Their mouths can be badly burned by chewing on electrical cords, sometimes so badly that they cannot eat. Thin plastic cord covers are insufficient, because rabbits can easily chew through these and have access to the cords inside after only moments. Instead, use PVC solutions like the examples shown here.
Baseboards: Rabbits should be deterred from chewing on hardwood, which can splinter in a rabbit's mouth and lead to potentially fatal medical emergencies. X-pens or small fences like the one shown here can be used to block off access.
Furniture: Wood furniture poses the same risks as baseboards, so chewing on hardwood furniture should be similarly prevented. Table legs can be protected with PVC tubing.
Access must be restricted to the area underneath upholstered furniture or exposed mattresses. Many rabbits have torn through fabric and gained access into sofas and box spring mattresses, where they can become stuck, exposed to other hazards inside the furniture, or become inaccessible to you in an emergency. Recliners with moving parts are potentially deadly. Barriers can be fashioned using NIC cubes, custom 2x4 framework, or other small metal fences, and must snuggly wrap around the entire perimeter of the object.
Plants: House plants and bunnies do not mix! Plants should be moved entirely away from the areas that your bunny can access. Moving plants onto a high shelf out of your bunny's reach is not enough; falling leaves still pose a potentially fatal hazard. Most houseplants are poisonous to rabbits and can cause anything from stomach upset, which is very serious in rabbits, to death.
Floors: All floor spaces accessible to your rabbit either within the pen or in play areas must offer sufficient traction. Slippery surfaces including wood floors, tile floors, smooth cardboard laid down on floors, etc, can result in both chronic skeletal issues and/or acute injuries. Choose carpeted areas for your rabbit to play, or add rugs with non-slip pads underneath.
Poisons: Rabbits are highly sensitive to anything in the air or on the surfaces in their environment. Air fresheners and essential oil diffusers can be very harmful for rabbits to inhale. Never use insecticides or other poisonous products in a home with a bunny.
Other rabbits: If you have two or more unbonded rabbits living separately, careful measures must be taken to ensure that they cannot access one another. Rabbits on opposite sides of one barrier can bite through bars and do extensive, lasting damage. Many rabbits have needed reconstructive surgery to repair noses that have been bitten in this way. Leave space between neighboring pens.
Pens and other barriers must be high enough that neither rabbit will jump over into the other rabbit's space. And remember, if you are bringing home a second bunny, the sight of another rabbit will be a huge motivator for your rabbit to find any flaw in the protective measures you have taken. Rabbits who have never jumped over a 30" tall pen, for example, will suddenly jump over a 36" tall pen if given sufficient incentive to do so.