From the UO Website: "Beginning on August 1st, 2006, the grace period for houses on inactive accounts will be changed from 90 days to 30 days. If your account remains inactive for more than 30 days, your house will begin a decay period of about 5 days. If you reactivate your account within the initial 30-day grace period or before your house finishes its 5-day decay period, then it will return to its original status."

No real problem for me, my 18X18 is  gone long time ago. *sighs*

If your account will be inactive for 30 days or more as of August 1st, it will be affected by this change. To keep your house, please reactivate your account by July 31st.

Please understand that our in-game support staff will not replace any lost houses or items as a result of this change, so don’t wait until the last moment to reactivate your account!

Click here for more information on housing and house decay.