This is part two of "Pet Urine, Scale of Severity." In part one we defined minor, light and moderate pet urine damage. In part two we will define severe damage.
Severe pet urine
The pet urine soaks the face fiber and the backing of the carpet and the pad and gets into the wood subfloor/floor. The buildup of dried lipids has made the carpet fibers sticky. Tack strip around the edge of the room may be rotting. Urine may have wicked up into the baseboard and wallboard.
Note: When the pet urine reaches the backing it spreads and when it reaches the pad it spreads and when it reaches the floor, you guessed it, it spreads. The area affected by the urine is usually several times larger than you can see from the top or the face of the carpet. This is not always the case. If the dog has sprayed small amounts of urine (marking his territory for example) then there is not enough volume for it to spread and the area may be no larger than what is visible.
If you have many minor or light problem areas in a single room and you are hand treating them yourself one at a time the problem may become a moderate or severe problem to you. Cleaning many light problem areas can become too big of a job. If you hire a professional carpet cleaner who deals with dog urine to come in and clean the carpets it should remain a minor or light problem to him. As long as the dog urine problem is only in the carpet face fibers, the professional can clean and treat the whole room at one time as though it was one large light issue. If you have a good carpet cleaning machine you can do it yourself. It is when the urine gets deeper into the carpet or into other areas (furniture, walls etc.) that the problem becomes moderate or severe and effective decontamination becomes more involved.
see also part one of "Pet Urine Scale of Severity"