I think this article covers inappropriate urination quite extensively:What You Should Know about Inappropriate Urination in Cats
Inappropriate urination, or urinating in unacceptable places, can be one of the most frustrating feline behavioral problems that many cat owners may have to deal with. However, by understanding the reasons behind this behavior and by utilizing retraining techniques and/or medical therapy, most cases of inappropriate urination can be resolved.
There are two types of inappropriate urination: house soiling and urine spraying. Behavior associated with house soiling is similar to normal urination. The cat will rake the ground, squat, and then will release a normal paddle on a horizontal surface, usually on furnishings such as carpets, rugs or other soft materials. On the other hand, urine spraying is a territorial or sexual behavior that has nothing to do with the physiological need for urination. The spraying cat typically stands with its tail fully erect and squirts a small amount of urine against a vertical surface such as the wall.
In all cases of inappropriate urination you should have the cat examined by your veterinarian as an underlying medical problem may be the culprit for the urination problem. In this case it therefore needs to be addressed before anything else. Cats with conditions leading to pain during urination will tend to avoid the litter box because they consequentially associate pain with it. The most commonly seen cause of painful urination is cystitis (inflammation of the bladder). For older cats suffering from arthritis, it can be painful to get in the litter box and to squat. Renal and endocrine disorders, like diabetes and hyperthyroidism, can lead to excessive water intake and increased urine formation, thus the cat may not be able to make it to the litter box on time.
In the vast majority of cases, inappropriate urination may be resolved if the primary cause can be treated.HOUSE SOILING
If no evidence of an underlying disease is found, then your cat may simply dislike something particular about the litter box itself. For example, it may take aversion to the location of the box. The litter box ideally should be placed in an easily accessible and quiet spot, a distance away from the feeding and playing area. It should also enable the cat to have a wide viewpoint so that it has the opportunity to see what's going on in the room.
Cats can often be put off by the texture or scent of the litter and certainly, most do not like a dirty and smelly litter box. You need to consider whether your cat's behavior started after a change in the brand of the litter. Experiment with different types of litter in order to check your cat's preference and take care not to overfill the box. It is also important to clean the box daily and wash it in a mild detergent at least once a week. You will need to rinse it well to ensure that all residual smells and remnants of detergent are removed. If you have more then one cat, make sure that each cat has its own litter box and it is a good idea to provide one extra box for the house.
Regarding the type and size of the box, most cats tend to prefer a large uncovered box that is easy to get in.
Another important cause of house soiling may be related to anxiety or stress. Cats are very habitual creatures and any disruption to the routine or change within the household can adversely affect them. Moving houses or refurbishing, arrival of a new child, competition between cats in a multi-cat household and separation from the owner are just a few examples.
Treatment of choice for anxiety-related house soiling will usually consist of reducing and eliminating the stress where possible, and/or behavior modification therapy. Evidence suggests that spraying house with Feliway, a synthetic equivalent of feline facial pheromones, induces a feeling of well being and calmness in cats. This method has proved to be efficient in decreasing or eliminating inappropriate urination in 30 to 60% of cases.
Pharmacological therapy may have a number of potential side effects and thus should be reserved for the more severe cases that do not respond to behavior modification techniques or environmental strategies. Several drugs have been proved to be effective in the treatment of anxiety in cats. Clomicalm (clomipramine) is commonly used for separation anxiety and single-cat households and BuSpar (buspirone) tends to be more effective in multi-cat households.URINE SPRAYING
If your cat is busy with urine marking or spraying, instead of finding puddles on the floor, you may see some remnants of urine on walls, doors, furniture or other objects. However, most noticeable will be the offending smell of your cat's 'perfume'.
You may find yourself asking the question as to why is it doing this? Leaving tiny but smelly messages is a means of communicating with other cats. Your cat is simply saying 'this is my territory' or 'hey, I'd like to offer my sexual services' or 'this item is mine'. Any cat can start to communicate this way, not only 'toms' as many believe, although tomcats are far the biggest offenders. Queens, especially when in heat, are more likely to spray then spayed females and the chance of spraying in multi-cat households is proportionally higher then in a single-cat household, irrespective of gender. In households where there are 10 or more cats there will be almost certainly at least one spraying.
Since urine marking is largely hormonally induced, neutering will eliminate this behavior in 80 to 95% of cases. However, don't expect instant results, as it may take up to two months before you start seeing any improvement. If your cat continues spraying after this period then there may be another cause as to why it feels the need to mark. For example, there may be a 'bully' cat in your neighborhood or other cats may be coming into your home through the cat flap. A new person or stranger in your house can also make your cat feel unsafe and insecure so it may feel the need to 'reinforce' its 'territory'. In multi-cat households, competition and territorial disputes between resident cats are a common cause of spraying.SOLUTIONS
If you haven't done so already get your cat neutered as soon as possible. Kittens can be neutered at any time from six months onwards.
Clean urine spots thoroughly. You can use white vinegar diluted with water (1:1) or commercially available enzymatic cleaners and odor neutralizers.
Provide each cat with one litter box each plus one extra for the house. Keep boxes clean!
Try to identify the reason why your cat sprays. If for example a new person has moved into the house, have him or her feed your cat to establish a bond between them.
Play with your cat in areas where it tends to spray.
If your cat sprays in only one room prevent access to this room. If spraying occurs in one or two specific areas and it is not possible to keep the cat out of this location, put a litter box or feeding bowls there. Most cats will not urinate around their food.
If there is conflict between your cats, you may need to isolate them, or at least the one which is spraying.
Spray Feliway in all areas where your cat marks.
Do not use household cleaning products containing ammonia for cleaning soiled patches - it could stimulate the marking behavior as urine also contains ammonia.
Do not punish the cat by dragging it to its litter box or sticking its nose in excrements and never hit it or kick it! In fact, you can make the matters much worse. Your cat will then associate punishment with you and may become timid and distrusting towards you. You will make it feel unsafe in the house and this will consequently lead to even more spraying. If you catch your cat doing the deed, you can try to deter it by making a harsh noise or spraying water from a water pistol, but in most cases this will not prevent the cat spraying in the future.
To conclude, you should always bear in mind that by the act of inappropriate urination your cat does not mean to upset you. There is always an underlying reason for its behavior that can be related to either physiological or psychological disturbances, or to a normal and natural behavior. If you are unable to resolve the problem, do not hesitate to seek advice from your veterinarian. Usually, your vet will examine urine samples for the presence of blood, sugar, crystals or signs of infection and possibly will take some blood samples if there is any indication of renal or hormonal problems, or diabetes. If your cat is in good health, your vet will be able to discuss the most appropriate behavior modification therapy and prescribe any medication if needed.Cat Behavior Problems