Garage Water Heater: Drain Pan Needed?

Water heaters are essential in every home, but they can cause serious damage if they fail. Water heaters are often installed in garages, and it is important to know whether a drain pan is necessary in this location. Drain pans are designed to protect homes from water damage due to leaks, and plumbing codes have changed over the years to reflect this. While the requirement for a drain pan depends on the location of the water heater, it is generally recommended to install one to prevent potential damage.

Water heater location

Water heaters are typically located in the home's garage, basement, or attic. They can also be placed inside the house, in a laundry room or utility closet, or even in the attic.

The location of your water heater is important as it can affect its efficiency, performance, and potential to cause water damage in the event of a leak.

If your water heater is in a garage, basement, or attic, it is usually placed on the floor or a platform. In these locations, a drain pan is generally not required unless the water heater is on a platform where leakage will cause damage.

When water heaters are installed inside the house, they are often required to have an emergency drain pan underneath. This is because a leaking water heater inside the house can cause significant damage to flooring, drywall, and personal belongings.

Additionally, local building codes and regulations may dictate specific requirements for water heater placement, such as the minimum distance from the floor and proximity to an external wall.

To minimise potential water damage, it is recommended to install a drain pan under your water heater, especially if it is located above ground level or in an interior living space.

Water damage prevention

Water heaters support a lot of water, and if they fail, they can cause serious damage to your home. Water damage prevention is therefore an important consideration when installing a water heater.

One way to prevent water damage is to install a drain pan under your water heater. Drain pans are designed to protect homes from potential water damage due to leaks. They are particularly important if your water heater is located in an attic or interior living space, as a leak could cause water damage to the ceilings and walls, promoting mould growth and structural issues.

The Residential Edition of the Florida Building Code (FBC-P2801.6) states that:

> Where a storage tank-type water heater or a hot water storage tank is installed in a location where water leakage from the tank will cause damage, the tank shall be installed in a pan.

The International Residential Code (IRC) has a similar requirement.

The plumbing codes have changed over the years, and one of these changes has made a drain pan a requirement in certain circumstances. The International Plumbing Code (IPC) specifies the requirements for constructing and installing these pans, including materials, size, and the necessity of an indirect waste pipe for drainage. Drain pans are made from durable materials such as galvanized steel, aluminum, or plastic, and must meet specific thickness requirements. They should be wider than the water heater and include a drain fitting to facilitate the safe discharge of water.

If you are installing a water heater in your garage, it is worth checking the building code in your area to see if a drain pan is required. In most states, drain pans are not required for water heaters inside garages. However, if your water heater is mounted on a wood-framed and drywall-sided platform, a pan and drain are necessary, as leakage will cause damage. Even if not required, a pan and drain are a good idea in a garage if there is a possibility that leakage could damage stored items.

Another way to prevent water damage is to install an automatic water shut-off valve, which will detect the presence of water beneath the water heater and turn off the water supply before extensive damage occurs.

Building and plumbing codes

The Residential Edition of the Florida Building Code (FBC-P2801.6) states that:

> Where a storage tank-type water heater or a hot water storage tank is installed in a location where water leakage from the tank will cause damage, the tank shall be installed in a pan.

The International Residential Code (IRC) has a similar provision.

The International Plumbing Code (IPC) specifies the requirements for constructing and installing these pans, including materials, size, and the necessity of an indirect waste pipe for drainage.

According to the National Fuel Gas Code, gas water heaters in residential garages should be installed so that all burners and burner ignition devices are located no less than 18 inches above the floor unless they are listed as flammable vapor ignition resistant. This is to prevent the ignition of any combustible fuels in the garage.

The South Holland Residential Code also states that water heaters with an ignition source should be elevated so that the source of ignition is no less than 18 inches above the garage floor.

However, drain pans are not required for water heaters inside garages in most states. The decision of whether or not to install a drain pan can depend on the location of the water heater and local building codes.

Installation locations

Water heaters can be installed in various parts of a home, including attics, basements, or even within living areas. The location can significantly impact the potential damage a leak could cause and, in turn, the necessity of a drain pan.

If your water heater is installed in an attic or interior living space, a drain pan is required under your water heater. Drain pans are not required for water heaters inside garages in most states. This is because the concrete floor of a garage is required to be sloped towards the garage door, so any leakage will drain out under it and not cause any damage. However, if the water heater is mounted on a wood-framed and drywall-sided platform, a pan and drain are necessary.

In addition, if your water heater is located above the ground floor of your home, a drain pan is important to prevent leaks from causing costly structural damage. Leaking water in a multi-level home will drip through walls and ceilings, causing water damage and potentially compromising the structural integrity of your house.

Therefore, it is recommended that you install your water heater as low in your home as possible, such as in the basement, to minimise the risk of water damage.

Material and installation specifications

Drain pans are made from durable materials such as galvanized steel, aluminium, or plastic. They must meet specific thickness requirements to ensure they can effectively contain leaks. Steel is the most durable option, but it is also the most expensive. Aluminium is a popular choice as it is almost as durable as steel but more affordable. Plastic pans are cheaper but less durable and prone to cracking.

Drain pans must be wider than the water heater and include a drain fitting to facilitate the safe discharge of water. The pan must also be deep enough to handle the water volume in case of a leak. The International Plumbing Code (IPC) specifies that the pan should be no thicker than 0.0236 of an inch (approximately 0.6010 mm). The pan should be at least 1.5 inches (38 mm) deep and should be large enough to catch any drips or condensation from the tank or water heater. The drain pipe should have a minimum diameter of 0.75 inches (19 mm).

The drain pan needs a drain pipe that leads to the outside of the building or a nearby floor drain. The drain pipe should extend to a minimum of 6 inches and a maximum of 24 inches above the ground surface.

To install a drain pan, follow these steps:

• Shut off the water lines leading to and from the water heater.
• Disconnect the service lines attached to the heater.
• Turn off the main power supply if you have an electric water heater.
• Drain the tank of water by opening the T&P valve.
• Lift the heater and place the drain pan under it, ensuring the discharge hole is pointing towards the drainage pipes.
• Place the heater inside the drain pan and reattach the water lines.
• Close the T&P valve and the drain valve.
• Place paper towels over the connections to check for leaks.
• Reconnect the supply lines. For a gas heater, relight the burner. For an electric heater, turn the main power back on.
• Attach the drainage pipe to the drain pan discharge hole.

Frequently asked questions