Pool liners only last for so long. Then, it needs replacing. If you’re a pool owner, you probably spend most of your time balancing the chemicals and cleaning debris from the water. But little by little, the pool liner develops tiny tears and stains.
Those little tears and stains begin to wear away at the integrity of your pool liner. Patches can only help for a short time; eventually, you will need a new pool liner. Here is everything you need to know about when and how to replace the liner on your vinyl liner swimming pool. I go over my exact process for both inground and above ground pools. Let’s get started.
- Your liner may need replacing due to damage from UV rays, nails and claws, expansions and contractions from temperature changes, yard shrapnel, and even chemical damage.
- Liners can last up to 20 years but generally need replacing after 10 years.
- When picking a replacement liner, make sure you get virgin vinyl with strong mil.
- When in doubt, hire a professional to replace your liner.
Signs That You Need to Replace Your Pool Liner
Pool liners last a long time – some last up to 20 years, but most need replacing after ten years. When you need a new one, you will know. There are several signs that you need to replace your liner. Pool liners become brittle, tear away from coping strips, and develop stains and leaks.
Damage from Ultraviolet Rays
We often place pools in the sunniest spots of yards, which means they get a lot of ultraviolet rays. The sun can damage the pool liner above the waterline and bleach it below the waterline.
Nails and Claws
Fingernails, toenails, and pet claws can create little tears in the liner. Those minor tears add up over time, which prompts the need for a new liner. Dogs and their nails are regular culprits for jagged tears in pool liners, especially when they try to get out of the pool.
Hot and Cold
If you live in a part of the world with four distinct seasons, your pool liner will expand and contract as the temperature cools down and heats up. The expansions and contractions can begin to pull the liner out of the coping strips, causing a lot of wrinkles. If your pool liner starts to sag and bubble, it might need to be replaced. Read my guide on how to remove wrinkles from your pool liner first, though – there are some things you can do to potentially save it for a while longer.
If you have trees in your yard or you use a lawnmower, there is a good chance that sharp objects could end up in your pool and tear your liner. During storms, tree branches, yard furniture, and other items we keep outside can land in the pool. Lawnmowers can also send objects flying into the pool.
The chemicals we put into our pools keep the water safe and clean, but those same chemicals wreak havoc on the liners. Chlorine does the most damage. Consider what chlorine does to clothing, and know it does the same to vinyl pool liners.
How to Choose a Replacement Pool Liner
There aren’t many options for above ground and inground pool liner replacements, but you should still have some information before you invest.
After all, the cost of replacing your pool liner can be significant. Consider the weather, warranty, and type of pool you have before you make your final choice. For more, you can read our complete guide on how to choose a pool liner. If you have an above ground pool, the manufacturer should stock a replacement liner.
Only Use Virgin Vinyl
Pool liners are made of vinyl. You want one made of virgin vinyl without any used, composite, or mixed products. Virgin vinyl is strong and will expand and contract for a longer time before weakening, especially when compared to other types of recycled or mixed vinyl. New vinyl will stand up to the chemicals and the UV rays that bombard it each day.
Choose Your Mil or Gauge
The thickness of your vinyl liner is measured in mil. A mil is 1/1000 of an inch, and a dime is 49 mil, which is 49/1000 of an inch. Most pool liners are 20 to 35 mil. While we might think a thick mil is better than a thin one, the quality of vinyl makes a difference. So, be sure you have virgin vinyl with a strong mil. Some manufacturers use the term gauge and mil interchangeably.
Many pool liners have different mil measurements for the walls and the floor. The walls get more UV exposure, so the mil should be thicker. If your pool mil measurements are 35/30, this means the wall has a 35 mil, and the floor is 30 mil. There will be a seam where the walls and floor meet when the mil measurements are different.
Read the Warranty
Your new pool liner will come with a warranty. Read the details, so you know what is covered. Some might have 20 years of coverage, but not for anything useful. The cost of the warranty should be justifiable based on the value it offers.
A new pool liner may be costly, especially for an inground pool, but it’s true that the better the materials, the higher the cost. Weigh your options carefully and know what to expect on pool liner pricing.
How to Measure for the Liner
Choosing your liner and your warranty is the easy part. The challenging part involves measuring the liner, especially if you have an inground pool that is not a rectangle or square. If you have a kidney-shaped pool or an unusual shape like a Grecian pool or L-shape, you might want the company replacing the liner to measure your pool. Draining your pool is helpful.
Unfortunately, there aren’t any standard pool shapes. The length and width might be somewhat standard, but the depth changes probably aren’t. And after inground pools are installed, they settle and change slightly. If your liner manufacturer has a template or measurement tips, follow them carefully because the measurements you send are what they will cut.
Keep in mind that if you are getting a replacement liner for an above ground pool kit, you likely won’t have to do this step because the manufacturer will stock a liner specified for your pool. However, if your above ground pool is custom-built and you do not already know the liner measurements, you will have to measure the liner.
As you measure the parts of your pool, record them on a drawing that represents your pool. The drawing does not have to be to scale.
If you do measure your liner yourself, you will need a few supplies:
- The manufacturer’s liner template or paper
- Pen or pencil
- Two 100-foot tape measures
- Two long roles of string
- Some helpers
- Utility knife
- Telescoping pole
Measure the Length and Width in Two Spots
The process begins with measuring the length and width of the pool in at least two places. When you measure, pick two parallel locations on the short and long sides, so you have accuracy. Do this for rectangular, square, and oval-shaped pools. If you have an odd shape, these steps do not apply.
When you measure the pool length and width, get in the pool and measure from liner to liner. Do not measure from the concrete or the coping outside the pool. The ends of the tape measure should touch the walls of the pool.
Some people find measuring easier with string. You can get these measurements with a string that you cut to size, then measure with tape afterward.
Measure Depths at Several Spots (Inground Pools Only)
This is where measuring can become complicated. Inground pools typically have varying depths and angles that are easier to measure when the pool is drained. Above ground pools are almost always level, so there is no need to measure the varying depths.
If your old pool liner has pulled away from the permanent floor of your pool, you may need to cut into it to get an accurate measurement from top to bottom. Only cut it if you are confident you are replacing it.
You should get at least three depth measurements. Get one in the deep end, one in the shallow, and one in the middle. Measure from the liner track in the coping to the floor of the shallow end. Do the same with the hopper. Also, measure a mid-point on the slope. Using string here is also helpful.
Measure the Length of the Floor
The liner company will need to know the length of the pool floor. From the inside of the pool walls, measure the shallow end from where the shallow end begins to where the liner attaches to the wall. You might want to enlist a friend to help with the next measurements.
Once you’ve finished measuring the shallow, move to the slope. Measure the slope from top to bottom. Then, measure the deep end where it is flat (the hopper). Finally, measure the deep end slope to the point where the liner attaches to the wall. You can use a length of string or a tape measure for these measurements.
Again, most standard above ground pools do not have a slopped floor, so your floor size should be the same as the length and width of the pool.
Measure the Hopper Width and Slope (Inground Pools Only)
Pools have various slopes that make the floor of the pool challenging to measure. At this stage, you will want two poles that you can measure. First, vertically drop one pole to the point where the side slope meets the hopper. Then, from the side of the pool, extend a horizontal pole to meet the vertical pole.
Where the poles meet is the slope measurement. You will get a measurement on the vertical pole and the horizontal pole. You will need both to get the slope measurement. Then, subtract the sidewall slopes from the entire pool width to get the width of the hopper.
Hire a Professional If In Doubt
If you cannot get accurate measurements, ask the liner company to do the measuring and pool liner installation. This way, if there is a problem, the fault is on the company and not you. They will replace the liner if they make a measuring error. If you make an error while trying your DIY solution, you pay replacement costs.
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How to Replace An Inground Swimming Pool Liner
The liner you purchase will come with installation instructions. Different types of pools have various necessities. For example, some pool liners need adhesives to hold them in place, while others are “floating” and use the weight of the water to keep the liner in place. If you are worried about proper installation, you can hire professionals to do the job.
You will need to drain your pool before you begin installing a new liner. Since pools have tens of thousands of gallons of water, you should check with your municipality, so you dispose of the pool water the proper way.
As your pool drains, you should gather the necessary tools, including:
- Push broom
- Utility knife
- Garden hose
- Special items like wall foam and adhesives if recommended by the liner manufacturer
Below are the general steps for replacing an inground pool liner. I also included a video from Inyo Pools that explains the process well.
Step One: Remove the Liner
Remove all of the faceplates and gaskets. Then, begin removing the liner from the coping tracks. You might need to cut the liner as you remove it because it is so bulky. Take all of the items out of the pool.
Step Two: Fix the Foundation and Walls
This could become a lengthy procedure if your pool has cracks or damage that needs repairing. Inspect the walls and foundation before you cover it.
Step Three: Prepare the Walls and Foundation
Manufacturers will have different steps here. Some might require you to install foam strips to stick to the walls and foundation. Follow the instructions here to prepare to accept the liner.
Step Four: Center and Attach the Liner
You will want to do this with bare feet to protect the liner. Center it on the foundation, then spread it up and into the coping tracks. Tuck it into place.
Step Five: Smooth the Liner
Using a shop-vac, suck the air out from under the liner. Remove a small section of the liner from the coping to insert the shop-vac hose. After you’ve removed the air, push the air out of the foundation with a push broom.
Step Six: Attach the Fixtures and Fill It
Once the liner is smooth and centered, you can reattach the facings, gaskets, and the main drain cover. Then, you can fill the pool. After you have a foot or so of water, check the liner and the fixtures to be sure everything is staying in place.
How To Replace An Above Ground Swimming Pool Liner
Replacing an above ground pool liner is a similar process to replacing an inground liner, with a few key differences.
Step One: Drain the Pool
Just as with an inground pool, your first step is to drain the pool. Depending on how big your above ground pool is, it can take several hours to drain. Make sure to check with your municipality and dispose of the water responsibly. You’ll also want to detach the return lines from the pool.
While the pool is draining, grab and prepare the following tools:
- Utility knife
Step Two: Remove the Return Jet from The Pool Wall
Unscrew the return jet until it comes out of the pool wall; you may need to use pliers to loosen the jet.
Step Three: Remove the Skimmer and Accessories
If your above ground pool has a skimmer assembly, remove it using a screwdriver or power drill. Make sure to keep all the parts and screws organized for when you reassemble. At this point, you should also remove the pool ladder, steps, and any other accessories.
Step Four: Unscrew and Remove the Rails
Remove all of the rails and top caps around the perimeter of the above ground pool using a drill or screwdriver.
Step Five: Remove the Liner
You might want to cut the liner into pieces using a utility knife to make taking it out of the pool easier. Cut it into several pieces and roll the liner up, exposing the bare ground underneath.
Step Six: Repair the Walls of the Pool (If Necessary) and Sweep the Floor
Make any necessary repairs to the structure of your above ground pool. Fix any holes or cracks in the walls, and fix any broken pieces. Check the manufacturer’s instructions, but some might recommend using wall foam to protect the liner. Use a rake or outdoor broom to sweep the dirt or sand on the floor of the pool, smoothing everything out and getting the floor as flat as possible. You can also install a floor guard for your above ground pool to protect the liner at this point.
Step Seven: Install the New Liner
Place the liner in the center of your above ground pool and begin unfolding it. Once unfolded, stretch the liner out to each edge of the pool. Start securing the liner into the top of your pool using a J-hook, or whatever other securing method your model has. Move around the perimeter of the above ground pool, attaching the liner to the pool structure as you go.
Step Eight: Begin Filling the Pool With Water
Start filling the pool with water and smoothing out the wrinkles on the floor with your feet as it fills with water.
Step Nine: Reinstall the Rails, Skimmer, And Return Jet
Reinstall the coping and rails of the above ground pool. And once the pool is about three-quarters of the way full, you can reinstall the skimmer assembly. Screw in the skimmer to the screw holes and cut away the liner that covers the skimmer opening. Install the return jet fitting into the return jet hole of the pool as well.
Step Ten: Smooth Everything Out and Enjoy!
Finally, finish smoothening out the liner on the walls of the above ground pool, let the water completely fill the pool, and enjoy your new liner!
How Much Does It Cost to Replace a Pool Liner?
The vinyl liner replacement cost will vary depending on your swimming pool size and the type and brand of liner you purchase. Above ground pool liners cost between $200-$1,100 on average. And inground pool replacement liners cost around $2,000 to $2,500 on average. If you hire a pool professional to install it for you, that could increase the price above $4,000 once you factor in labor and materials.
How to Make Your Pool Liner Last Longer
No pool liner lasts forever, but there are steps you can take to preserve it. For example:
- Balance the pool chemicals properly (and often)
- Don’t use abrasive cleaning materials or products
- Keep your pet out of the pool, or at least offer an easy way for them to get out
- Install a cover to protect the pool when it’s not in use
- Tend to small punctures as soon as possible
For more on this topic, read my article answering the question: how long does an above ground pool last?
Inground swimming pools require significant maintenance. Fortunately, big projects like replacing the liner only need to be done once every 10 to 20 years. Take your time to measure and install the liner properly, so the replacement lasts as long as possible. And make sure to protect your liner from tears too! If you think you have a leak, read my guides on inground pool leak detection and how to find an above ground pool leak for tips on locating and fixing it.
Questions? Let me know; I’d be happy to help.