Q. My dog just started peeing in the house all the time & I walk him tons I don't know what's going on
DAVID ELBEZE, DVM, MRCVS
A. This could be because he is drinking a lot (could be caused by several diseases such as diabetes, renal failure, hypothyroidism) and needs to go often to urinate.
If he isn't drinking a lot, it's more likely to be a urinary infection or behavioral (related to the fact he is not neutered).
It would be best to take him to the vet for a checkup, you might want to bring a fresh urine sample with you (in a clean plastic container) as you vet might want to check the urine first.