If you move into a house where an oil heating system is already installed, it probably wouldn't even cross your mind to check the size of the heating oil tank. On the other hand, if you're planning or designing a new build, or remodeling an old property, determining your heating oil requirements is an important factor.
You might also be replacing a damaged or outdated tank, and you need to ensure that the new tank is the optimum size. It must be large enough so that you don't run short of oil at a critical moment, but not so large that it costs too much. Knowing the capacity of your tank also allows you to calculate correctly the amount of heating oil you'll need to purchase from your best-priced local dealer to fill it up.
A lot depends on where you live and the size of your home. If you're among those Americans living in the north and northeast, heating is going to be a crucial factor in your household budget. There are some 5½-6 million households in America who choose oil to fuel their heating systems, and more than 80% of those are located in the northeast.
You can calculate your likely heating oil needs by the number of rooms you're wanting to heat and how many hours a day and months per year you'll want to heat them. As a general rule in the industry, homes with one or two bedrooms need a heating oil tank that holds 275 gallons, while homes with three or four bedrooms will require tanks holding 300-500 gallons.
Where the tank is situated is also important, as you need enough space for the size of tank you choose. You might find yourself running out of oil in the winter because your tank is not big enough, but perhaps you don't have enough physical space to install a larger one. In this event, it might be possible to find a different location where you can put a tank that is correctly sized for your needs.
The size of your family also matters, and whether this is likely to change in the future. If you're planning on having children, or will become carers for older family members, you'll need to plan for a greater heating oil consumption in the future. You should also take your family's lifestyle into account when making your calculations. If you're keen to keep your consumption down for environmental reasons, perhaps, or if you're away a lot on business or vacation, you'll likely be using less oil than average.
There are two main measurements you'll need for sizing your tank: its physical dimensions (height, depth, width/diameter) so as to fit it into the required space, and its volume capacity in gallons, so you know how much oil you need to fill it up.
The capacity of residential heating oil tanks is always measured in gallons, and if you have an existing tank this may be marked somewhere on a label affixed to it. If you can't find a label (and many older tanks don't have them), you'll have to measure it yourself and use a formula or online tool to calculate the capacity.
Oil tanks also come in different types, which have their own range of standard sizes. These can go from 250 gallons to 30,000 gallons or more, but residential heating oil tank sizes are a standard size 275 gallons. You can get these small domestic tanks in a standing or lying down orientation, which are annotated on the listings as 275V (vertical) or 275H (horizontal).
This size of tank is usually installed above ground, but there’s a whole range of sizes that can be installed either above or below ground. The most common sizes in gallons for home heating tanks are 288, 340, 420, 500, 550, 675 and1,000 gallons, though tanks for underground installation can be much larger.
Once you know how big your tank is and how much oil it holds, you can work out how much oil you have left in it. Newer models usually have a built-in gauge, but if you need to calculate manually, you'll need a dipstick. You can use a rigid tape measure, or even just a long pole, which you dip into the oil tank. Measure how far up the pole the oil mark is and enter that measurement into the online calculator to see how much is left.
Once you've worked out your consumption (and you can do this every month if you want to monitor it closely), you'll be ready to order your oil for winter. Click here to find the best-priced dealers in your region.