When it comes to building concrete pools, pool contractors typically specialize in either shotcrete or gunite. There are distinct benefits that come with building a shotcrete pool and some clear benefits that come with gunite pools. While Gunite is very similar in terms of the pool construction process, there are a few differences between Shotcrete and Gunite that we will discuss today. First however, we shall cover the similarities between the two in terms of how inground pools are constructed.
Shotcrete or Gunite, Which is Best?
For many homeowners considering an inground pool, around 50% will opt for a concrete pool constructed of either shotcrete or gunite material. There are benefits and drawbacks to each application and if you ask pool builders around the country most will explain why their method is best and cite some of the reasons listed here. As far as building concrete pools, these 2 methods are the most popular. Concrete pool builders either specialize in Gunite or Shotcrete.
Differences between Shotcrete & Gunite
Shotcrete and Gunite are mainly comprised of a blended mix of sand, cement, and aggregate materials. When introducing water to the mix is the primary determinating factor of whether it is Gunite or Shotecrete. Shotcrete is pre-mixed and shipped to the homeowners property in a cement truck. The wet mix was combined prior to arrival and is ready to be shot out of a nozzle when it arrives on site. Gunite however, is mixed however on site with a dry / wet mix that happens right at the nozzle. The concrete mix is made right then and there during the application process.
Benefits of Shotcrete:
- Typically it takes less time to apply shotcrete than it does to shoot gunite.
- Creates less rebound material leading to a stronger pool shell with greater integrity.
- Pre-mixed off-site prior to arriving to the job site and is ready to apply on arrival.
Drawbacks of Shotcrete:
- Greater risk of shrinkage cracks forming than with Gunite.
- Typically the material is more expensive than Gunite.
- Lower max PSI strength than Gunite (7,500 psi).
Benefits of Gunite:
- Gunite material gets harder as it cures over time.
- Prepared on site giving workers more time to prepare the job site and finish other phases.
- Higher PSI strength (up to 9,500 psi)
- No cracking due to shrinkage
- Typically cheaper material
Drawbacks of Gunite:
- Easier to miscalculate the water to cement ratio and more room for human error.
- Increased risk of rebound material forming and being used during construction.
- Structural integrity could be compromised by weaker areas utilizing rebound material.
- Limited structural applications and special paint needed for gunite interior finish.
We polled pool construction companies all over the country and asked them which method they was better, Shotcrete or Gunite.
Which is better Shotcrete or Gunite?
Currently the results seem to be favoring Shotcrete as the preferred method for Pool Contractors and Pool Construction companies. We reached out to some of the companies we surveyed and asked them why they voted the way they did. Here’s what Custom Pools of Miami, FL had to say. “We opt for Shotcrete because it takes less time to apply and forms way less rebound than Gunite. Shotcrete creates a much stronger pool shell with better integrity and less weak spots.”
Southern Poolscapes, however made their case for why Gunite Pools are superior to Shotcrete Pools. “Gunite has a higher PSI strength. It’s true that Gunite creates more rebound, but if water needs to be added to the pre-mix which it frequently does, that negates the benefits. It’s also more costly for the homeowner if the company makes a mistake and shrinkage cracks occur. Shrinkage cracks are uch less common with Gunite.”
They both make compelling arguments for choosing Shotcrete over Gunite or vice versa. It’s safe to say however, that no matter which pool company you select – if they are experienced and veteran pool builders that it shouldn’t really matter whether a particular builder chooses shotcrete or gunite. It’s clear that they both have their benefits and drawbacks. Seasoned pool builders may opt for one over the other due to prior experience with the material, availability of subcontractors in the local area, and costs of material. In some markets it’s more advantageous for a pool builder to opt for Shotcrete over Gunite and in other markets Gunite will be the go-to solution. It really boils down to preference more than whether one product is superior over the other. In the end, there really is no clear indication that one product is better.