Urinary Problems/peeing in my house! HELP!

I have a 13 year old cat whos had urinary problems all his life. Well he keeps getting infections and he is peeing in my house instead of going in his litter box. I'm finding it all over. In the tub, in the basement there are peices of plastic on the floor (we are in the middle of finishishing it) and he's peed on that. Also on my carpet in corners!!! I can't take it anymore! I've been thru 3 prescritions of Baydril from my Vet and he's still doing it. What can I do????? Is there anything I can give him??? Please help as I'm desperate, its getting so bad I almost wanted to put him outside!

Put the cat in ONE room with his litterbox and food. Put 'pee pads' on the floor. Do not let him into other rooms.

Your cat may have an illness or a UTI. A good book on the subject (THE CAT OWNER'S MANUAL by Dr. Bruce Fogle) states that older cats may pee outside the box 20% of the time. Your odds are certainly higher.

Please do not put the cat outside since this will almost certainly lead to his death if he is going senile (a possibility.)

He's had Urinary track infections all his life. This is what he's experiencing right now. When he has a flare up, he pee's everywhere. Is there anything I can give him to help this?

If he has a UTI now they may need to try another antibiotic. If he has been taking the same one he may have built up an immunity to it. Is he on a special diet for this problem? As suggested I would confine him to one room and definitely not put him outside.

Well I have to take him into the vet today, they want to do an xray and check his urine. I'll be yelled at for not keeping him on his diet, which I thought I was to be using C/D and found out its X/D I'm supposed to be using. I'm sure I'm in for a ear full.