99% up time commitment is a common service level agreement in most web hosting plans. However once you dig deep you will discover that it doesn’t include down network time, down hardware time or sometimes even any issues caused by operating system. Most often a business starts to discover these issues when the phone rings and an angry customer is on the other side. Often times situation gets so bad that you end up looking for new hosting recommendations.
First thing to do is to always call your hosting companies. Sometimes you can even end up getting a discount on webhosting for downtime.
Secondly you can get a monitoring service to keep an eye on hosting up time.
Last but not least you can ask around for new hosting company recommendations.