Swimming Pool Blog
by Rob Cox, August 18, 2010
How to replace an above ground pool liner
Sooner or Later, your above ground pool vinyl liner will need to be replaced. Generally, above ground liners last 10 years or so, depending on the quality of the pool liner and the care given to the water chemistry. Over time, harsh water conditions can deplete the plasticizers within vinyl and cause your vinyl liner to become brittle and stiff. Eventually, all liners will fail, some gradually, some tragically and all at once.
Your pool liner also may become a victim to animal damage, ice damage, or a team of soccer players who forgot to remove their cleats before swimming. More likely, it will develop pinholes in areas of chemical degradation, or when becoming stiff and "crispy" after years of low pH or high chlorine levels, it may suddenly "snap" one day, creating a long horizontal tear along the wall which cannot be patched.
Or perhaps you are one of those above ground pool owners I have seen on America's Funniest Videos, driving your ATV / Tractor / Lawnmower into the side of the pool, flooding the backyard. In any case, all liners fail, so this blog post is for those DIY-ers who wish to save big bucks by changing their own above ground pool liners. You can do it !
1. Assemble your Supplies: Order your new vinyl pool liner. Measure carefully before ordering. Measure from wall to wall, at both the top of the pool, and at the base of the pool wall to be sure that the walls are not bowed in or out. Never assume that you know the size of your pool, to avoid costly delays. Measure the wall height, at several areas around the pool. Liners are available standard in sizes of 48", 52" and some 54" wall height. Make sure to order the correct pool liner size and depth!
Overlap liners are a fairly easy selection, however overlap pools can also use what's called a J-Hook, Uni-Bead or a Hung liner, which hangs on the pool wall, eliminating the need for coping strips. Beaded liners are available with more pattern options and a printed tile-like border. Overlap liner pools can be also be converted to use a beaded liner, with the use of a bead receiver, which are hung on the wall, creating a track to receive a beaded style liner.
Other items possibly needed include pool floor padding, which can smooth out uneven floors, and prevent small rocks and roots from damaging your new pool liner. Not very thick, only 1/8", but very effective if you discover that the sand beneath your liner is rocky, rough or stained with algae. In lieu of floor pad, you may consider having a yard of graded sand (not masonry sand) delivered.
Wall Foam is a good idea for pools with galvanized walls that may have developed rust over time. Pool Wall Foam will protect your new liner from rough and rusty wall surfaces, and also provides some added protection against punctures in your new vinyl liner. Wall Foam also just feels nice to the touch.
Pool Cove are triangular pieces of foam, 4 feet long, that are placed at the base of the pool wall. This provides protection from rough and rusty bottom rails and the base of the wall which can develop rust faster than areas of the wall which are higher up. Pool Cove also gives a nice transition from floor to wall, and again a nice feel. Many installers build up a cove of sand during installation, again as a way to form a barrier between a rusty wall base and your liner, and to provide a slighly shallower depth for younger and shorter swimmers. Sand however, can change shape over time and become uneven, whereas foam pool cove will retain it's shape and form for much longer.
Other supplies that may be needed include new faceplates and gaskets for the skimmer and return lines. If these plastic / rubber items have become brittle or cracked, it is advised to replace them during a new liner installation. New coping strips for overlap vinyl liners should also be inspected for integrity. If you are in need of structural components of the pool, such as new top rails, seat clamps, uprights or bottom rails, these can be hard to come by. Screws and Clips may be obtained at a local hardware or home store, but the previously mentioned items are not standard, and vary by pool manufacturer. If these are necessary, try to contact the original manufacturer of your pool to inquire about replacement structural pool components.
2. De-construction: Drain the pool using a submersible pump. You will need to remove all of the water before you are able to remove the liner. To get out the last bit of water, a large sponge and a bucket or a shop vac can be useful. After the water is removed, use a razor knife to cut the liner at the base of the wall. Using a properly sized (large) screwdriver, remove faceplates from the skimmer and return fittings. Remove the wall portion of the pool liner first, keeping the floor section in the pool until you are ready to do the floor prep.
For an overlap liner, remove the top rails and seat clamps to gain access to the coping clips. Be cautious not to lose any screws, and keep different screws and clips separated to avoid confusion. If the liner can be removed without removing the top rails, this is highly preferable. For beaded or J-Hook liners, pull the bead up and out of the track, no need to remove the top rails.
Avoid heavy walking or jumping in and out of the pool, which will cause divots and create more floor prep work for you. Some areas of the country have the ability to recycle vinyl, check with your local landfill.
2. Wall and Floor Preparation: Inspect the wall for corrosion or mineral deposits. Scrape smooth with a putty knife or drywall knife. Rusted areas should be covered with wall foam, or at least spray painted with a rust converting type of paint. Duct tape should be placed over wall joints to hide their appearance if wall foam is not being used. If wall foam is used, a spray adhesive is applied to hold the wall foam. Usually 2-3 cans is sufficient - the entire wall does not need to be sprayed with adhesive to hold the foam.
When ready to prep the floor, remove the remaining floor portion of the liner. Your pool floor may be sand, or it may be vermiculite, which has a concrete appearance.
If your floor is sand, inspect the sand for roots, rocks and deep green algae, spending time going over it slowly, picking out debris and even small pebbles. Adding sand is not always necessary, but you may need to replace some. Use caution not to add too much sand to the pool floor which will raise the height of the floor. An overlap liner can be adjusted, but a beaded liner will form wrinkles if the floor is raised too much. If adding sand, you should measure from the floor to the track, or top of the wall to make sure the liner won't be longer than the available depth.
Smooth out the sand, using large plaster trowels or a 4' piece of 2x4 wood before spreading out the floor padding. Place a stake in the center of the pool, and run the other end to a stake that you place at the wall. Adjust the stakes so the string is level (use a level) and 1" above your sand level. Work your way across the pool, keeping the floor level as you go Another method to check level is to place the level on a 2"x4"x8' piece of wood, and move this with you as you trowl around the pool. I find the string method easier and if you want to be really accurate and level - use both methods, moving the string and the 2x4 around the pool with you as you trowel the floor smooth.
If you are using a vinyl liner floor pad, it's a good idea to spread out the floor pad several hours before installation, stretching it tight to remove the packing wrinkles. Remove all rocks and roots, which can damage your new pool liner. Make sure that the depth of the sand is even all the way across, and that the base of the wall is covered equally all the way around the pool's edge. Then carefully spread out the floor pad, using some wide heavy weight on the sides so you can pull it tightly.
If your pool floor is vermiculite, you will now appreciate the extra money spent during the original installation. Sweep clean with a broom, and patch any cracks with a lightweight cement, (or vermiculite) or at least fill with sand and trowel smooth. Floor padding can also be used on a vermiculite bottom, for a softer feel, and to cover up any imperfections.
3. New Pool Liner Installation: Read the label on your liner box, make sure the size is the same as you ordered. Open the box and lay the liner out in the sun, or in cold climates, keep the liner indoors, warm until ready to install. Unroll the liner to the full length or width of the pool, allowing packing wrinkles to relax. When ready to "drop the liner" have several persons on hand to assist, Lay the liner across the pool, and carefully stretch it out across the pool, being careful not to drag across your nicely troweled sand. If using floor padding, be similarly cautious to avoid bunching up the floor padding.
Several sets of hands at this point are very useful to get the liner stretched around the pool, while keeping it off the floor as much as possible. If an overlap liner, use binder clips or clothes pins to hold the liner in place temporarily until the entire liner is over the wall. If a beaded liner, use pennies or popsicle sticks to shim the liner into the track temporarily.
After the liner is in the track or attached to the wall, adjust the liner so there are no wrinkles. Using a pool brush on a pole, tap the liner around the edge to pull out floor wrinkles. For overlap liners, pull the liner over the wall just far enough so that the liner is barely off the floor, or resting gently on the floor, without wrinkles. You may need to spend considerable time adjusting the liner to avoid wrinkles, which will give you problems in keeping the floor clean, and create areas more prone to damage later on.
Oval pools will have a definate point at which the radius begins, and you will need to adjust the liner to match the start and end of the radius. Expandable liners, used on some doughboy pools, allow for a deep end on an oval pool or a deeper center on round pools. These liners require special treatment to stretch into place properly without placing undue stress on the walls or the liner itself.
When you are satisfied with the placement of the liner, and you have all the wrinkles worked out, so to speak, attach any coping strips and reassemble top rails and seat clamps between the rails. If a beaded liner is being used, the liner should hang from the track snugly. If loose, use liner lock as a shim to take up any slack and prevent the liner from popping out of the track, now or later.
If you find that you have wrinkles or excess liner on the walls, you usually just need to twist the liner away from the slant ( / ) of the wrinkles. If you have many wrinkles on the floor that you can't work out (and it can take some time, be patient) - you may have raised the level of the floor too much. Major bummer, remove the liner, and remove some of the sand. Overlap liners can just be pulled over the wall more - problem solved. But beaded or j-jook liners don't have this flexibility. Another option to remove small wrinkles before filling the pool is to use a vacuum / blower like the Mighty vac to set your pool liner. This powerful vacuum hose is put behind the liner, and duct taped tightly. This sucks all the air out between the liner and the floor/walls, and gives a nice fit. Used always on in ground vinyl liner installations, it can be used also on above ground liner installation - but usually is not necessary.
4. Final Steps: Turn on the water! If the water volume is especially heavy, wrap a sock around the end of the hose to diffuse the water, and prevent erosion or divots beneath the liner from the force of the water. As it fills, check for wrinkle formation, and with your pool brush, try to bang out any wrinkles toward the pool edge. If this doesn't work, lean over the edge, grab a handful of liner on the low wall, and yank it towards the wall. Floor wrinkles need to be pulled out before getting too much water in the pool, when they become impossible to work out. Keep an eye on it during filling, checking every few hours if possible.
When the pool is nearly full, replace the skimmer faceplates and return fittings. Doing this earlier can create problems as the liner will continue to stretch as the pool fills. Use a properly sized screwdriver to install the faceplates and tighten them very tightly, until you hear the plastic begin to creak, but before it cracks. Once the faceplates are installed, use a razor knife to cut out the vinyl inside of the faceplate. You can save these for use later on as a patch if needed.
Now you are ready to start the filter, balance the water and enjoy your refurbished pool! You can do it!