When a building's domestic hot water storage tanks start showing their age, most boards hear the same advice. Replace them. Sometimes that's the right call. But for most large tanks, it's the expensive answer to a problem relining solves for a fraction of the cost.
Here are the questions boards and property managers ask us most, with straight answers.
Why are large tanks worth keeping?
Large domestic hot water tanks are usually set in place before the walls go up, and the building is often built around them. That makes them an asset of the building, not a consumable. Keeping the tanks you already have in good shape is almost always the cheapest long-term option.
Will a relined tank last as long as a new one?
For a large tank with a manway, yes. These tanks were designed with manways, replaceable anodes and gaskets, and a cement lining so they could be maintained instead of thrown out. A tank we look after from new never needs to be replaced. We service it regularly, reline it every 10 to 15 years and repair any weld or fitting issues as they come up.
Older tanks are a different conversation. If a tank has gone decades without service, nobody can promise what condition the steel is in until someone looks inside. But relining combined with weld repairs can save nearly any tank, as long as the steel is in decent condition overall. An internal inspection tells you which situation you're in.
What about smaller tanks?
Everything above applies to large tanks with a manway. Smaller glass-lined tanks don't have a manway and can't be relined. They're built to be replaced. In our experience they last up to about 10 years when they're not maintained and closer to 20 when they are. Regular anode replacement, sediment cleaning and fitting checks make that difference, and help you plan replacement on your schedule instead of in an emergency.
Do tank manufacturers allow field relining?
Yes. Field relining is approved by tank manufacturers. Hydrastone manufactures Alkrete, the cement lining Canadian tank manufacturers apply in their factories. When we reline a tank on site, we're restoring the same lining system the tank was built with, not substituting a coating it was never designed for.
Can a cement lining handle hot water temperatures?
Yes. Domestic hot water tanks are meant to run at 140°F (60°C) and above, and Alkrete is formulated specifically for hot water tanks. It's used in tanks operating well above 140°F.
Is the work warrantied?
Yes. Every Hydrastone reline comes with a written warranty. Ask us about the terms when we quote your building.
How much does relining cost compared to replacement?
Large tanks are very hard to get in and out of a building. Removing one can mean cutting it apart, and the new tank has to be rigged into a mechanical room that was built around the old one. That's why replacing a large tank is often a six-figure bill. Relining is typically less than 10% of that, and even with a weld repair it's still a fraction of the cost. Over the life of the building, maintaining the tanks you have is the cheapest option.
What about replacing it with smaller tanks?
A large tank can be replaced with a bank of smaller tanks, but that usually costs more over time. Smaller tanks are often disposable, lasting as little as 10 years when they aren't well maintained.
A bank of smaller tanks also needs more piping, more valves, more fittings and more insulation, and every one of those is something that can go wrong. When any of it isn't perfectly maintained, the system loses heat. A plumber removes insulation to make a repair and it never goes back on, or a small leak never gets fixed. That heat loss shows up as a higher utility bill, and the insulation itself is expensive to replace.
Stainless steel tanks are another option, but they're much more expensive.
When is replacement actually the right call?
When the steel itself has failed. That means corrosion that has spread through the tank body, widespread deep pitting, or a shell that has leaked through in several places. A lining can't restore steel that's gone. The only way to know is to look inside the tank.
What should the board do next?
Get an internal inspection before approving a replacement. Hydrastone offers a free tank assessment with a written recommendation covering maintenance, repair, relining or replacement planning. Call 416-902-8265 in Toronto, 778-996-8265 in Vancouver or 403-466-8645 in Calgary, or email info@hydrastone.com.
