Cooper started wearing his size two when he was about seven months. This means we've been using these cloth diapers for about five months. In the last month or so, I've noticed that after Cooper peed in his diaper, it smelled very strongly of ammonia--and that his bum was getting red. I did some research and found out that our diapers had ammonia build up and I needed to strip my diapers. Occasional ammonia build-up is a completely normal part of cloth diapering and is easily resolved. Stripping Cooper's diapers was easy. I simply ran them through a pre-wash like I always do to remove the traces of solid waste and rinse out most of the urine. To really get the ammonia build up out of the diapers requires a more intense process than a regular wash, so the next step was adding about two tablespoons of regular blue Dawn dish detergent and washing the diapers on hot for a full cycle. Then I rinsed them about four times until all the bubbles were gone in the rinse. After I pulled out the diapers, I gave them a quick smell. They had a lingering scent of dish soap but I couldn't detect the ammonia smell anymore. I knew the true test would come when Cooper wet the diapers. As soon as the diapers were dry, I put them to the test and thankfully the powerful ammonia smell was gone! I've learned a few tips to about how to prevent ammonia build up: Put your diapers out to dry in the sun. The sunlight helps to disinfect them and bleach out stains and nothing gets out smells like fresh air! Instead of tightly sealing up your diaper bin, allow in some air . This helps to prevent the ammonia from building up inside your diaper pail. If you are over-powered by an ammonia smell when you dump your diapers from your pail to your washing machine, you have ammonia build up! Don't let your diapers sit for more than a few days before you wash them. This also helps to prevent the ammonia gas from building up. If you are stripping Duo All-In-Ones, I suggest you turn them inside out. And don't forget to separate out your diaper covers after the pre-wash. They do not need to be stripped. Our Thirsties diapers are once again back to normal and so is Cooper's red bum. Stripping them was much easier than I had anticipated and well worth the effort. Have you had any problems with ammonia build-up in your cloth diapers? If so, please share your secrets and tips!