When adding a bedroom to your home one should check the records on the existing septic system to determine the bedroom rating. For example, adding one bedroom to a 3 bedroom home, if your home is currently a 3 bedroom home and you have a 3 bedroom septic system then you would have to upgrade the septic system to a 4 bedroom system in order for the number of bedrooms to match. This is important when you sell your home and are required to obtain a Health Approval from the Municipality as part of the home closing process.

You can obtain  your records at the Municipality of Anchorage, Department of Health and Human Services, Onsite Services Division at 9th and L street between the hours of 7:30 and 11:30 am or call 343-3744

If you know the size of your septic tank you can roughly determine the bedroom capacity by this method:
1000 gallons = 3 bedroom
1250 gallons = 4 bedroom
1500 gallons = 5 bedroom

This should also be checked with the city as sometimes the tank is oversized.

If it is required to upgrade the system a new tank will have to be installed or an additional one added in series if there is room to place the tank or the original tank is not over 10 years old. A soil test will be required and a permit. This is the same procedure as building a new septic system and is covered in our information for building a new home on a separate web site.