Fiberglass Shell vs lining whats the difference?
A fiberglass shell otherwise known as a fiberglass drop in shell is exactly as the name describes. It is a precast fiberglass shell which has been moulded into a specific shape and size. It gets delivered on a truck to the client and cannot be bumped, dropped or hit against anything while offloading it.
Before the delivery takes place a team which the client chooses to do the work, will usually come in and dig the hole according to the shape and size of the fiberglass shell which you have chosen. When it arrives it is just a matter of getting the shell to the hole and dropping it in hence the name “Drop in Shell”.
Now this is the easy part but it gets a bit complex if the pool company who is installing it does not know what they are doing, as the shell cannot just be placed into a hole and filled with water. It requires what we call a backfill of cement-stabilized sand (a sand-and-cement mix) or clean crushed stone/gravel for structural stability and proper drainage. Normal sand cannot be used as it holds moisture, shifts easily, washes out, and can liquefy or cause pool walls to cave in or shift.
Once the shell is in place and your backfill is ready the team will need to plumb the shell and connect the light which is usually included with the pool. Where is gets complicated is when you start filling the pool with water as this step will either make or break the shell. The water level should fill to the exact level of the backfill so what I mean by that is as the water is filling the pool the team will have to push the backfill of sand in the exact measurement of the water fill. If this is not done and the water level rises above the backfill level the chances of the pool cracking is almost promised as the pressure pushes the shell outwards and due to the complex nature of the shell been like a hollow bathtub you will need something to resist the pressure such as the backfill.
This is usually the cheaper option to go for if you are wanting a pool in a hurry at a cheap cost. Do we recomment it? No we do not. I say this because a person does not know how the shell was loaded onto the truck, if precaution and care was taken or if it was bumped and dropped. So even thou the shell gets delivered in one piece you will never know the answer to the questions until it is to late then you cannot blame the company who delivered it or the company who sold it to you. They also require 50% when you order and the other 50% before they will offload the fiberglass shell,which leaves a person in a situation where they cannot simply withhold the money till they test it which i think is not the correct way but hey that is just me.
Fiberglass Lining
A fiberglass lining is a concrete pool which has been lined with a chop strand fiberglass matt. What this means is you converting a marbelite pool into a fiberglass pool by casting a shell inside of a shell.
This was is much more practical but takes slightly longer to do as you need to wait for curing times between processes. Depending on the pool company you use it can be cheaper or more expensive than buying a drop in shell.
If you still unsure of fiberglass shell vs lining, we do suggest calling a professional to advise you like North side pool services.