Fibreglass Septic Tank
Poly / Plastic Septic Tank
(Example of a Premier Plastics Septic Tank shown to the left)
Concrete Septic Tank
(Example of a Alberta Wilbert concrete septic tank shown to the left)
Steel Septic Tank
.... so which one is "best"?????
Well, that isn't necessarily easy to answer. It's like asking if an apple is better than an orange. Different tanks, different applications.
But, to keep it simple, I am going to give you a quick breakdown of pro's and con's of each.
Fibreglass and Poly (Plastic) Tanks
-Light (compared to concrete), fairly easy to transport with small machinery.
-Usually less expensive than a concrete tank
-Custom shapes/sizes are easily constructed
-They are normally only rated to 1-2 meter (4 foot) burial.
-They aren't ideal in high water table areas as they are very buoyant and can "pop" out of the ground very easily without proper anti-flotation measures.
-Rated at much deeper burial than fibreglass or plastic. Great for deep burial circumstances.
-Better choice for areas with high water tables. They can still "float", but not as easy as fibreglass or plastic.
-Usually cost a little more
-Very strong, very durable. Lighter than concrete but heavier than fibreglass and plastic.
-Non-reactive with most septic waste.
Here in Alberta, with rough winters and ground heaves, tanks are usually buried deep. Concrete is usually the choice. Most concrete septic tank companies make it easy for the contractor/homeowner and deliver and place the tank with their own equipment for a small fee. There are, however, many different "grades" of concrete tanks with large differences in quality.
Fibreglass and plastic tanks, in my opinion, have less options than a concrete tank when it comes to design/installation configurations. For example, a home with plumbing in a basement will not be able to use a fibreglass or poly tank unless a lift station is installed in the home or immediately outside. Fibreglass and plastic tanks are a great option where deep burial is not needed.