Are you thinking about installing a double walled heating oil tank? You have come to the right place.
What is a double walled heating oil tank?
Does it mean there is an inner tank with a second tank on the outside that is cosmetic only?
Is it two layers of steel welded together?
Does it mean plastic & fiberglass shells?
Does it mean two tanks?
Basically, a double walled tank has a primary tank, or inner tank, that actually holds the heating oil or diesel fuel, and a secondary tank, or outer tank, that not only protects the inner tank, but in the event that the inner tank leaks, the outer tank will hold the contents of the inner tank, thus preventing a spill of product on the ground.
Double Bottom Oil Tanks
But why just cover the bottom with a double layer and not the entire tank? Well, there are 2 reasons for this.
First, the cost. in order to keep the tanks as affordable as possible only the bottom is protected with a double layer.
Second, leak protection. For oval shaped residential tanks, 99% of the time if the tank develops a leak it will be on the bottom of the tank. You see, all of the sludge that builds up over time in the bottom of tanks causes tank deterioration from the inside out. Also any water, moisture or condensation in the tank settles to the bottom which also degrades the tank. So if you are going to protect something from leakage why not protect the area where all the leaks come from?
Are double bottom tanks a good option for a tank upgrade over a base model?
YES! Definitely.
Double Containment
Certain tank situations require a dike or containment device around the tank. This is used so that, in the event a spillage or a tank leak, the containment device will hold any of the oil or diesel fuel from seeping into the soil. This double containment is usually a separate vessel that surrounds the tank like a box or trough.
Where Can I Get a Double Walled Oil Tank?
There are several tank manufacturers that produce For aboveground residential heating oil tanks, here at GreenTRAX we primarily work with Granby & Roth.
GRANBY TANKS

Talking strictly about double walled tanks, Granby makes 3 different series.
ECOGARD SERIES – Comes with a 25 year warranty and a double bottom. This series comes in the 275 and 330 gallon size models of vertical tanks. These are electrostatic coated powder paint.
ECOPLUS SERIES – Comes with a 30 year warranty and a double bottom. This series comes in the 275 and 330 gallon size models of vertical tanks. These tanks are polyurethane coated and have a UV protection coating.
2-IN-1 DOUBLE WALLED TANK SERIES – This is truly a double walled tank with a 30 year warranty. The tank is a boxy/rectangular shape and comes in 190 gallon and 265 gallon sizes. The inner tank is polyethylene and the outer tank is galvanized steel.
ROTH TANKS

All Roth tanks are double walled with the inner wall being 100% seamless polyethylene and the outer wall of lead-free galvanized steel. Roth tanks come standard with a 30 year manufacturer’s warranty and $2 million of leak insurance, which is a great benefit for those homeowners who choose this tank. These tanks are 55% lighter than 12 gauge steel tanks, so for those tanks installed in basements, when we have to maneuver the tank down steps and around tight corners, there is less chance of scrapes or dings because these tanks are much lighter and easier to move around.
Roth tanks are available in 110, 165, 275 & 400 gallon sizes.
Are double walled tanks worth the extra cost?
YES definitely, then you can have peace of mind knowing that you likely will never have to worry about that heating oil tank for as long as you own the property.
After all of this, should you consider buying a tank with either a double wall or double bottom? Well, we think so. But it also depends on other factors, such as:
- how long are you planning to stay in the house?
- how old is the furnace or boiler?
- where will the tank be located – inside or outside?
Call GreenTRAX today and we will explain the new tank options and warranties and help you find the best tank to fit your budget.