What Kind of Gravel to Back Fill Fiberglass Pool

Frequently Asked Questions

How long does a pool take to install?

Do you offer financing?

Do you handle the landscaping?

Do I need to get my own permits?

What is the cost?

Fiberglass vs Vinyl Liner vs Gunite Concrete: Which type of pool is best?

Because we offer more than one type of pool, and because there is an array of various sizes, shapes, and options it's best to contact us with what you are looking for in a pool before we can give an accurate estimate of your pool cost.  You can submit your information here and we will be more than happy to contact you to get started making your backyard dreams a reality.

We do not offer in-house financing, however we do have partnerships with reputable lenders to assist with your financing needs.  You can learn more about financing here.

What is included in your pool installation?

Basic Pool Installation Includes the Following:

• 4 Pool Returns (minimum)

• 6 Hydro Stone surface colors

• 1 Skimmer with self adjusting weir plate

• 4 Feet of perimeter concrete decking

• 3500 PSI concrete decking with control joints (reinforced with rebar)

• 2 anti vortex bottom drains (anti-entrapment) skimmer and main drains are plumbed with valve (independent of each other)

• Equipment timer

• Energy efficient pool pump

• Filter

• 3 way equipment valve

• All equipment has union disconnects

• Cantilever concrete coping (standard)

• Standard maintenance kit (16' telepole, wall brush, leaf net, vac head, vac hose, and vac plate)

Do you offer salt water systems?

We do offer salt water systems as an available upgrade.  We can give you the upgrade cost when you contact us for your pool estimate.

Length of installation is dependent on the project itself. Some projects take longer than others, but our average installation time is approximately 3-4 weeks.  We focus on one project at a time and never have more than 2 pools being installed at once.

No, we will get any permits required.

Once a homeowner has decided to make the investment into an in-ground pool, one of the very first and most important questions they will need to consider is what type of pool they would like to have installed.  There are three types of pools available which are fiberglass, vinyl lined, and Gunite concrete.

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We have previously installed all three types of pools, but have recently stepped away from concrete construction because we only want to provide our customers with the very best possible pool, and feel we can accomplish this best with either fiberglass or a vinyl lined pool.  That being said let's take a look at the advantages and disadvantages of each.

We do not handle the landscaping ourselves, however we have a company that we recommend for your landscaping.

Fiberglass

Advantages

• Warranty - Fiberglass pool are built to last and most manufacturers provide a LIFETIME STRUCTURAL WARRANTY.  We only install Trilogy Pools® which have this lifetime structural warranty.  To learn more about Trilogy Pools® click here.

• Fast Installation - Because the pool shell is made offsite they are much quicker to install than the other types.

• Little Maintenance -  Fiberglass pools have a smooth gel coated surface that resist algae and does not react with pool water balance resulting in fewer chemicals to maintain your pool.

• Less Electrical Use - The water only needs to circulate 4-6 hours each day.

• Minimal Lifetime Cost - No liner replacement or resurfacing is required.

• Built In Features - Steps and sitting areas are molded into the pool and included in the cost of the pool.

Disadvantages

• Limited designs and sizes.  However, more advances are made each year to create more options.

• Width Limitations - Because the shell of the pool is made completely off site and has to be freighted they have to be 16' or less in width.

Vinyl Liner

Advantages

• Initial Cost - Of the three types of pools a vinyl lined pool costs the least to install.  However, loan acceptance for a vinyl lined pool is lower than that of fiberglass or concrete.

• Customizable Shapes and Sizes - You are not limited by a pre-manufactured shell when designing your pool.

• Nonabrasive Surface - Vinyl liners are smooth to the touch.

• Low Maintenance - Just as a fiberglass pool requires less maintenance and is resistant to algae because of it's smooth surface a vinyl pool is as well.

Disadvantages

• Greater Lifetime Expense - Although initial cost of a vinyl lined pool is less it will actually cost more than a fiberglass pool over it's lifetime.  Pool liners will need to be replaced on an average of every 7 years costing between $3500-$4500 to replace.

• Liner warranties are minimal.

• Built In Features Are Additional - Steps and seating are not built into the cost of your pool and are an additional fee.

• Liners are more susceptible to damage.  A liner can be punctured by tree limbs, pets, or other sharp objects if not careful.

• Lower Resale Value - A vinyl lined pool does not hold as much real estate value as a fiberglass or a concrete pool.

Gunite Concrete

Advantages

• Most adaptable to the size and shape you want.

• Durability - Unlike with a vinyl liner there is no fear of objects puncturing or damaging the pool.

Disadvantages

• Costly - This is the most costly type of pool to install.  Features such as steps and seating are an additional cost.

• Lifetime Cost -  Not only is Gunite concrete the most costly to install it is also the most costly over the lifetime of the pool.  It will most likely need refinishing every 5-7 years and is also recommended that it is renovated every 10-20 years.

• Concrete is porous and permeable requiring more chemical use.  Plaster reacts to the water affecting pool balance.  The porous structure harbors algae which requires acid baths and more scrubbing.

• Electrical Use - Water needs to circulate 8-10 hours daily which is twice as much as with a fiberglass pool.

• Longer Install Time - Concrete pools can take 2-4 months to fuller install.

What type of backfill do you use?

We use gravel backfill as opposed to sand.  Here is a great excerpt from an article written by Jason Hughes at River Pools and Spas, out of Virginia, explaining why gravel is a better backfill than sand.

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"If you talk to enough people or scroll through enough online forums you'll probably come across someone who has developed a bulge in the wall of their fiberglass pool.  We encountered this problem years ago with several of our pools.  This caused us to scrutinize our installation process and thoroughly inspect the pools where these problems occurred.  What we found flies in the face of the standard and accepted method of installing fiberglass pools across the country.  The problem in our case stemmed from the backfill material that we used.....namely sand.  Tens of thousands of fiberglass pools have been installed with sand backfill without incident, and most of our sand backfilled pools were fine as well.  But when the right (or wrong) combination of circumstances align fiberglass pool walls do bulge.  Question:  What happens to sand when it becomes saturated with water?  It liquefies.  That would be fine if the liquefied sand were resting against something other than fiberglass which is renowned for its flexibility.   Fiberglass pools are structurally engineered to remain full of water.  The outward pressure from the water works in conjunction with the structure of the pool to stabilize the vessel.  When sand liquefies it is heavier than the water on the inside of the pool and if the wall is not strong enough to maintain its shape a bulge develops.  High water tables as well as soils that hold water both lead to situations where a significant amount of water surrounds the pool structure and saturates the backfill material.  So does this mean that fiberglass pools are not suitable for installations with high water table or certain soils?  Quite the contrary; I would submit that there is no better pool to have in such circumstances.  You just need to make certain of two things.  First, that you're pool is strong enough to prevent bulges.  And second, that you eliminate the sand backfill and use gravel.  Is there a difference between the strength of fiberglass pools?  Yes, but from the perspective of the consumer it will be virtually impossible to rate the "bulge-ability" of the various pools on the market because all manufacturers claim to be the strongest and most stable.  The one thing you CAN control is the backfill material, and based on our experience, using gravel backfill is the only insurance against wall bulges in any situation with any pool.   Clean crushed blue stone ¾" or smaller is the gravel used in our installations because it has several distinct advantages over sand or even round pea gravel.  First, its properties do not change when it becomes saturated with water so it performs the same wet or dry.  This makes it ideal for any situation and especially in areas with a high water table or difficult soil conditions.  Second, the point on point friction that occurs between the pieces of gravel make it a very stable material on the sides of the pool; much better than saturated sand that liquefies or pea gravel that acts like little ball bearings.    Third, the gravel compacts upon placement unlike sand which needs to be placed in lifts and compacted with water.  This is further addressed in the discussion on plumbing problems below.  You will see that this is a major advantage as well.  Opponents to gravel backfill pitch against it by saying that it's a cheaper material and used in order to cut cost.  In reality it actually costs us significantly more to use gravel.  We feel it is well worth the investment because you can't put a price tag on peace of mind........... Why would the plumbing settle?  Good question!  The plumbing doesn't settle, the backfill material around the fiberglass pool settles and takes the plumbing with it.  Yes we're back to our sand vs. gravel discussion again.  This is great because this is a topic that needs attention.  The problem is that it's very difficult to fully compact sand around a fiberglass pool during installation.  Many times, despite a fiberglass pool installer's best efforts to bring the sand up in 6"-12" lifts and fully saturate the sand with water, the sand still settles some over time.  The plumbing is encased in this sand and as the sand settles, it exerts downward pressure on the plumbing of the swimming pool.  Many installers tie their plumbing up to help hold it in place, but not withstanding, that's still a lot of pressure.  Settled plumbing manifests itself in one way....leaks.  "Leak" is a dirty word!  We want to avoid saying that word, and we do so by using gravel backfill that just doesn't settle!  If the backfill doesn't move, the plumbing doesn't move.  It's as simple as that!"

So the main points to take away are as follows.

• Gravel does not change when it becomes saturated with water; wet or dry it performs the same.

• Point on point friction of gravel makes it much more stable unlike sand that liquefies.

• The gravel compacts upon placement unlike sand which needs to be compacted with water.  This also makes the installation process much faster when gravel is used.

Ready to Start Creating Your Backyard Oasis Today?

* This is an estimation of cost over a 10yr period.  Costs will vary depeding on usage and region.

What Kind of Gravel to Back Fill Fiberglass Pool

Source: https://www.creativepoolsokc.com/faq

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