Purchasing the proper size septic tank for your home will determine how often you must clean out of pump out the tank. On average a septic tank will need to be pumped out every 3 to 5 years. Before purchasing any tank you should check all local codes and regulations. In many areas the minimum size tank allowed for residential application is 1,000 gallons. This is to insure the home has adequate capacity in the event it is sold to a large family.
How To Know What Size To Purchase
There are three different methods which can be used to calculate the tank needed for your home. Each of these has its advantages as well as drawbacks. The efficiency of any tank can be increased or hampered by the habits of the homeowners. By limiting the amount of water entering the system, keeping harmful chemicals out and by not using a garbage disposal you can greatly increase the efficiency of the system and reduce the frequency of pumpings required. Each pumping will cost approximately $350 to $400 depending on the area in which you live.
The larger the tank you select the higher the initial investment. Larger tanks can also be more expensive to install and to have cleaned out. Careful consideration should be given based on your long term needs and plans. If you are a young couple, but you intend to have a large family, you will need to plan based on future needs rather than current needs.
Septic Tank Size Based on Water Usage
According to Aquacraft the average person will use 171.8 gallons of water in their home each day. The largest amounts of water are used for the toilet and clothes washer. Since the amount of water entering your septic system is critical to its performance, tank size is often based on the amount of water entering the system daily.
Based on the water usage stated above, if you have 3 residents in the home, you will use approximately 515 gallons of water. With four persons this usage goes up to 687 and with five persons it climbs to 859. If your water usage is 500 gallons or less, it is estimated you need a 500 gallon capacity tank. If your water usage is from 501 to 600 gallons of water you will need a 1000 gallon tank. If your usage goes up to 700 gallons a 1200 gallon tank is recommended. From 801 to 900 gallons you should install a 1500 gallon septic tank.
Septic Tank Size Based on Number of Bedroom
The number of bedrooms is used as a means of calculating tank size because it is assumed each resident of the home will need or occupy a bedroom. This will also supposedly insure the home has adequate tank capacity if all bedrooms are occupied even if only one bedroom is currently occupied.
A one or two bedroom house will require only a 750 gallon tank. A three bedroom will need a 1,000 gallon tank while a four bedroom home will need a 1200 gallon tank. A larger home with five or six bedrooms will need a 1500 gallon tank or larger.
Septic Tank Size Based on Cleaning Frequency
The final method of calculating the needed septic tank size is to base it on the estimated time between cleanings. This system is based on the average time between cleaning if the tank is maintained properly. There are many variables which will determine the frequency of cleanings required so this method has a larger margin for error.
There are charts available showing numbers for occupants from one to ten. The numbers below are for a household with four occupants. With a 500 gallon tank, with four occupants, the tank would need to be cleaned annually. With a 750 gallons tank cleaning would be required every 1.8 years. A 1,000 gallon tank will need to be emptied every 2.6 years while a 1500 gallon tank will need to be emptied every 4.2 years.
Determine your current needs, your future plans and select the proper tank size for your home.
