With new-pool orders at a near standstill, the renovation bandwagon is becoming crowded.

But don’t jump on too fast. Any renovation project means dealing with a product that was originally built by someone else, and the pool is only as good as their workmanship. In addition, the passage of time can cause a multitude of other, unrelated issues.

“You definitely have to be more on your toes with renovation, because you can potentially have more problems,” says Jeff Kearns, president of Wildwood Aquatech Pools in Fresno, Calif. “I’ve noticed very good pool builders getting into renovations, and they can get in trouble, at least for the first few.”

There are a number of key areas that must be carefully checked before bidding on any renovation job. Be sure to examine the pool’s structural condition, plumbing, electrical system and interior finish. Here, renovation experts discuss exactly where to look to help anticipate potential pitfalls.


The underlying structure of a pool functions like a skeleton, and if the bones are too weak, the vessel and surrounding deck may not be viable. Be sure to spend the necessary time carefully checking for structural problems. Here is where attention should be focused.

  • Soil conditions

The hazard: Without proper support from the earth, a pool can shift and crack. This is particularly important if you’re going to add a spa or waterfeature.

How to find out: Unfortunately, there’s no completely reliable way to confirm soil conditions without digging. That said, obtain as much information as possible from the customer, including a copy of surveys. If you’re doing demolition work on the structure, visually check to see if you detect two distinct types of soil, such as in a cut-fill transition. 

Needed repair: You may need extra support on the pool, deck or added features.

If the surveys indicate the site is on problematic soil, or your own sleuthing suggests differential or expansive soils, consider consulting a geotechnical engineer. When embarking on major structural work on a hillside, do the same.

  •  Structural strength

The hazard:  Adding spas, waterfalls or other features to a structure that isn’t strong enough to support them will result in eventual cracking or other failures.

How to find out: Consult an engineer.

Needed repair: If the existing structure can’t support the additions, the engineer will explain how to provide needed support. Specifications may require a footing or suggest a way to beef up the current structure.

  • A pool’s levelness

The hazard: The pool may have settled or lifted, a likely problem if it was left empty for long. If so, your work won’t be level, and the waterline will appear slanted across the tile.

How to find out: Examine how the waterline sits on the tile. If it looks higher in one area, then that part of the pool is lower, and has settled. If the pool has been emptied, check with a laser or transit level.

Needed repair: If there is no cracking, and the pool was built several years ago, the structure likely will be fine. On pools newer than 5 years, observe over time to see if cracking occurs. If the timeline will allow, monitor the shell through a complete wet/dry cycle.

More often, this problem is simply cosmetic and can be fixed by building the low spots up with mortar. You can do this easily if the pool’s off by an inch or less. More than that, however, and adjustments may throw the coping out of alignment with the deck. In that case, you’ll need to redo the deck to the right elevation, or let it be.

“Then the homeowner has to decide if they want to level that pool,” says Ron Robertson, president of Robertson Pools Inc., a Pool & Spas News Top Builder in Coppell, Texas. “That could be another $2,000 to $4,000 or more.”

  • Perimeter expansion joints

The hazard: Decades ago, it was common practice to pour the deck right up to the pool structure (or over it, in the case of cantilever decking) without a separation. This is a fundamental construction flaw that can prematurely age a bond beam.

“The deck is expanding horizontally into this vertical wall of the pool, and the pool loses every time,” says Steve Toth, owner of Acclaim Pools in The Woodlands, Texas.

With no expansion joint in place, the coping may have dislodged or the bond beam broken. This is caused by the pressure of the deck expanding and contracting, and degradation from water entering cracks.

How to find out: Visually check for the expansion joint where the deck meets the coping. If you see tiles popping off, the joint’s likely missing or inadequate. Also, look for horizontal cracks in the tile line, as that could indicate that the bond beam is breaking in that direction. Larger, 6-by-6-inch tiles make these cracks easier to see. Smaller tiles can flex with the bond beam and need to be inspected more closely. Randomly tap tiles around the pool with a small hammer to see if any feel loose.

Needed repair: It depends on the severity of the problem. It may be necessary to jackhammer out the damaged area and redo it. Simply replacing the tile is not adequate, as it will start dropping off or cracking soon.

  • Vertical cracks

The hazard: Cracks that run down the wall could indicate structural problems, especially if they are wider at the top and thinner on the bottom.

How to find out: It can be difficult to see pool cracks through the water, but take a look anyway during the initial consultation. Also check the coping, since cracks starting there sometimes continue down the wall. Investigate further after the pool is emptied, but before it is stripped. Cracks are harder to detect once the interior finish has been chipped out.

Needed repair: This typically indicates differential settlement, often from soil issues, says structural engineer Ron Lacher, president of Pool Engineering in Anaheim, Calif. Hire a geotechnical or structural engineer to determine the underlying problem and solution.

Some homeowners don’t want to pay for this and prefer that the cracks just be repaired. But these solutions are temporary. “Often when you do crack repair and weld the cracks together, you make it really strong there,” Kearns says. “But in a year or two, it might crack next to what you mended. So you have to be sure you’re addressing the problem first.”

If the homeowners aren’t willing to pay for an engineer, have them sign a waiver, or consider walking away from the job. If soils issues continue to hurt the pool, you may be held responsible as the last contractor on the site.

  • Rebound

The hazard: If the original builder hid rebound in the shell, it has probably deteriorated over time and/or delaminated from the rest of the concrete or interior surface.

How to find out: Check areas that are popular for hiding rebound — skimmers, benches, steps, coves and dam walls. If the pool is empty during your first consultation, tap around with a small hammer and listen for a hollow sound. If not, then perform this check after draining.

Needed repair: Rebound means that the area should be re-shot. “If it’s just made out of rebound, I know that it’s going to be deteriorated pretty badly,” Toth says. If this isn’t fixed, your handiwork will be hurt by the long-term damage.

  • Fiberglass coatings

The hazard: Fiberglass coatings may hide a serious problem lurking underneath.

“You could almost bet that the pool was [coated with fiberglass] because it had some structural damage,” Robertson says.

How to find out: This probably can’t be addressed until after the bid is approved, since it requires stripping the coating away. But before the customers sign, warn them that these finishes are generally used to repair cracks and other problems.

Needed repair: It depends on the severity of the problem. Repairs can range from epoxy doweling or stapling cracks to demolishing and reshooting part of the pool.


If the structure of a pool is its skeleton, then the plumbing serves as the veins and arteries that keep water flowing properly. Leaking, damaged or unsafe plumbing can cause a multitude of problems down the road.

  • Leaks

The hazard:  Leaky pools waste water and can have structural problems.

How to find out: Perform a pressure test to indicate underground leaking. To check spa jets, Toth drains the vessel to below the seats and lets the interior finish dry for about 45 minutes. He then looks around the outlets to see if the finish is wet there. “If so, it’s probably because they snugged up the flex pipe too close to the steel,” he says.

Needed repair: In the case of the spa returns, this could indicate long-term damage to the structure. “It’s been blowing chlorinated water into the gunite and just eroding away,” Toth says. The pressure test will warn you of some plumbing leaks. Robertson’s company offers to perform this service for an added cost, and leaves it up to the customer to decide.

  • Damaged or non-PVC plumbing

The hazard: Anything other than PVC pipe likely indicates a very old pool, or a poorly built new one. Metal plumbing or black poly pipe don’t hold up as well against chemically treated water.

How to find out: Check around the equipment. However, exposed PVC plumbing in the pad could have been added when equipment was replaced and doesn’t always translate to the whole system.

Needed repair: Offer to install PVC for the long-term durability of the pool. If the customer balks, explain that the wrong plumbing could cause leaking, and even settling or cracking over time, as water seeps into the shell and surrounding soil. Be insistent if you find flex pipe, Toth says, because it doesn’t hold up as well as rigid. If you find non-PVC pipe, realize that you have an old pool on your hands and proceed accordingly.

  • Skimmers

The hazard: While it’s becoming standard practice to put two or more skimmers in the pool, past methods often only called for one. This limits the in-pool water circulation, hampering the effectiveness of heating and chemicals. In addition, some pools have old copper skimmers that should be replaced with the more chemically resistant PVC. If you notice rebound around the skimmers, you also have a potential problem.

How to find out: Count the skimmers and lift the lids to make sure everything is made of PVC. Sometimes older, metal skimmers are concealed with a newer lid.

Necessary repair: Adding a second and even third skimmer might be necessary, depending on the size of the pool. Metal skimmers should be replaced. And if you find rebound at the skimmers, they should be reshot.

When repairing or replacing skimmers, it isn’t enough to cut out the beam and put a new one in, Toth says. Be sure to dig out the gunite or shotcrete around the skimmer, cut the rebar that you need and lap new rebar. You must lap it by 30 times the diameter of the bars. For instance, if dealing with No. 4 steel, overlap the old and new by 15 inches — 30 times 1/2 inch.

  • Check drains

The hazard: Drain safety has been a predominant topic of discussion since the Virginia Graeme Baker Pool and Spa Safety Act was passed in 2007. Without a properly installed drain system, users could run the risk of entrapment – especially in shallow water.

How to find out: Look for dual drains. If the pool has them, make sure the drains are connected. This can be done by forcing compressed air through the skimmer to see if it bubbles out both drains, or sending the air into one drain to see if it comes out the other. If the pool is empty, use water instead of air. Look at the drain covers to make sure they’re not flat or loose.

Necessary repair: If the pool has a single main drain system, check state and local codes. You’ll need to determine, first, whether they apply to renovations and, second, whether they call for dual drains, a safety-vacuum-release-type system or both.


An unsafe or out-of-date electrical system can result in injury or even death. Carefully check a few key areas to make sure everything is in order.

  • GFCI’s, grounding and bonding

The hazard: Pools built before the 1960’s won’t have electrical safety measures in place, since the National Electrical Code didn’t begin requiring them until 1962.

“Old electrical can be very dangerous, so it’s often one of the first things that you’re bringing up to code,” Kearns says.

How to find out: If you’re dealing with an older pool, make sure a qualified electrician sees it.

Needed repair: If any of these safeties are missing or non-functional, they should be fixed. This can get costly, particularly if you hadn’t planned to tear up the deck. It’s important to note that electrical systems must be updated in some areas for a permit to be issued. Even if the repair is not required by law, it should be highly recommended for safety reasons. If the customer refuses, it’s a good idea to have them sign a waiver.

  • General condition of the electrical system

The hazard: Damaged wires, boxes and conduits could fail in the near future. They could simply be tangled or messy, causing a potential tripping or snagging hazard.

How to find out: Look at the wires and boxes to make sure everything is in good shape and properly connected. If digging up the deck, check all conduits for corrosion.

Needed repair: Replace items that are damaged. Clean up items that are in the way.