BlueHost is a great host homeriscool. This is BlueHost's Network / Server Uptime Agreement from there helpdesk:
Source -
http://helpdesk.bluehost.com/
Network / Server Uptime Agreement
We at Bluehost strive to offer the best in the industry for Network and Server uptime. Like all shared hosting companies from time to time we experience downtime.
We Guarantee! that our network will stay up 99.9% of the time.
Server uptime on the other hand is dependent on a variety of issues, ranging from the activity by our clients, traffic to other sites, hardware failure, to issues like hard-drive failure and file corruption. Most issues are resolved in approximately 15 minutes, however on extreme issues it may take more than 15 minutes to resolve the issue. In these extremely rare circumstances the server may require additional time to resolve the issue. This can take several hours and in very rare cases as much as a day to get your server back up and running.
We at Bluehost, unlike most hosting companies, will not charge you for leaving your hosting agreement early due to server downtime. Furthermore, we allow you to cancel your account at anytime without any penalties and with a pro-rated full refund of the unused portion of your hosting agreement.
At any time, should you have questions or comments, feel free to contact us via Phone, Live Chat or our E-mail ticketing system. Our support lines are open 24/7. We appreciate your business and look forward to a continued relationship of honesty and trust.
Yours truly,
Bluehost Management and Staff