Indoor Cages
Cavy experts agree that an indoor guinea pig cage is the best home for your pets, for a number of reasons. Living outdoors brings with it a number of perils, such as predators, bad weather, and increased risk of illness. In fact, guinea pigs who live indoors have been shown to live longer than those kept outside. By letting your cavies live in your house, they will feel like part of the family, and as a result they'll be happier, healthier, and better stimulated.
If you really must keep your guinea pigs outdoors then you will need to buy a purpose-built guinea pig hutch; a normal indoor cage will not provide your animals with the protection and comfort that they need. However, you should think very carefully before making such a decision, and do your best to house your pets inside - they really will benefit from it.
Size
Exercise is critical to your animals' health, and guinea pigs love to run around as fast as they can. To do so, they need a large, open area which is clear from obstructions. They also need enough space to be able to get away from their cagemates for some 'alone time' once in a while. Experts used to recommend cages which nowadays are considered far too small. In fact now, almost everyone now agrees that the bigger the cage, the better. For specific information about what cage size your pigs need, please refer to Teresa Murphy's fantastic site Guinea Pig Cages, which will tell you everything you need to know.
Shop-Bought Cages
Most pet stores and several specialist websites offer a wide range of cages for sale. Sadly, the vast majority are little more than a cramped enclosure, and aren't nearly large enough. Some shops even sell generic cages which are meant to be suitable for all types of rodents. However, guinea pigs are much bigger than hamsters, gerbils, and mice, so these cages are definitely too small.
One important point to bear in mind when measuring a cage, is that you need to measure the internal dimensions where your guinea pigs will actually be living. Most manufacturers quote the external sizes, making their cages seem bigger and more suitable than they really are.
C&C Cages
An increasingly popular alternative to regular guinea pig cages are 'Cubes and Coroplast', or C&C cages. These are cages that you can build yourself from readily available materials. The cage itself is actually constructed from wire mesh storage cubes, which are very cheap to buy, and can be found in a number of hardware and home-furnishing stores. These simply snap together in any configuration you desire, which means you can make a cage of any size, or even extend an existing cage quickly and easily. The floor of the cage is made from a type of corrugated plastic commonly known by its brand name 'Coroplast'. Again, this is quite easy to find, and is inexpensive to buy.
C&C cages are fantastic for a number of reasons. Firstly, and most importantly, they provide your guinea pigs with the space they require to live comfortably. They are also very easy to clean, because they don't have lots of nooks and crannies like some shop-bought cages do. They are generally cheaper as well, because you do the construction yourself (this is very simple, so don't worry if you aren't a big fan of DIY!). Finally, they are very easy to extend or reconfigure, making them perfect if your cavy family expands, or if you just want to give your existing pets more room to run around in. Again, the Cavy Cages site will tell you everything you need to know.
Location
Once you have bought or assembled your cage, you'll need somewhere to put it. Often, people put their guinea pigs somewhere where they won't be 'in the way'. However, by doing so, you're missing a great opportunity to bond with your cavies and to make them feel like part of the family. Guinea pigs are very sociable animals, and love to have lots of human contact, so it's much better if you can put their cage in or near a busy family area. This way, they can experience the hustle and bustle of family life, and really feel welcomed.
When choosing an exact location for your guinea pigs' cage, try to find somewhere that benefits from plenty of natural light, but isn't in direct sunlight. Also be sure to avoid drafty areas, as guinea pigs are quite sensitive to breezes. Rather than putting your pigs' cage on the floor, it is better to put it on a table or stand which raises it up to around waist height. This puts them around head height when you are sitting, so they can feel involved in the family. It also makes it easier for you to pet them, top up their water and food, and clean their cage out.
Bedding, Toys and Accessories
Your guinea pig will need a few supplies to keep them happy and entertained. Perhaps most obviously are a food bowl and water bottle. Look for a fairly heavy bowl, as lighter ones tend to get tipped over easily, sending your pets' food flying! Water bottles should be mounted to the cage wall and checked regularly to ensure they are filled with plenty of clean, fresh water, and to make sure they are working correctly and your animals can reach them. Cover the cage floor with a layer of black and white newspaper or soft bedding material, and then top with plenty of clean hay. Finally, you should add a small selection of toys and accessories to your guinea pigs' cage, so that they've got something to play with. However, be careful not to put too many in, or your pets might not have enough room to live and run around.
Cleaning
Indoor cages are generally quite easy to clean, simply requiring you to lift out the old bedding, throw it away, and replace it with fresh materials. You should also clean out your pets' food bowl and water bottle, and refill them. While cleaning the cage, you might want to consider changing its layout, moving around your guinea pigs' toys and accessories to provide a bit of variety and stimulation for your pigs.
An indoor guinea pig cage really will give your pets the best life possible. It will make them feel involved in the family, and also help to protect them from illness and predators. In return, you will be blessed with a more active and energetic pet which will provide endless hours of fun.