Do you know whether your building has a wet or dry sprinkler system—and why?
For Edmonton building owners and property managers, understanding the difference is especially important. Your sprinkler system type affects where the system can be used, how it needs to be protected from freezing, and what your fire protection company needs to inspect and maintain. Keep reading to learn more about these two types of fire suppression systems, the differences, and how Karlen-Kada can help install, inspect, and repair fire protection equipment in Edmonton.
Wet Pipe vs. Dry Pipe Sprinklers at a Glance
Both wet and dry sprinkler systems are water-based fire protection systems, but they operate differently.
| Factor | Wet-Pipe System | Dry-Pipe System |
| What is normally inside the piping? | Water | Pressurized air or nitrogen |
| What happens when a sprinkler is triggered? | Water discharges from the opened sprinkler | Air pressure drops, the dry valve opens and water enters the piping |
| Where is it typically used? | Areas where piping can be protected from freezing (interior locations with consistent heating) | Areas where water-filled piping may be exposed to freezing (outdoor areas or mechanical rooms) |
| System complexity | Generally simpler | More components and operating considerations |
| Water delivery | Water is already in the piping | Water must first enter the protected piping |
| Maintenance considerations | Overall system condition and freeze protection where required | Air pressure, dry valve operation, drainage, moisture and overall system condition |
Both wet and dry sprinklers have their own unique considerations. Let’s discuss these systems in more detail.
How Does a Wet-Pipe Sprinkler System Work?
A wet-pipe sprinkler system keeps water inside the sprinkler pipes at all times.
When enough heat reaches a sprinkler head, that sprinkler opens and releases water. The sprinklers do not all go off just because the fire alarm sounds.
Because the water is already in the pipes, wet-pipe systems are fairly simple. They are usually used in areas where the pipes can be kept warm enough to prevent freezing.
Advantages of Wet-Pipe Sprinklers
Some of the main benefits of a wet-pipe sprinkler system include:
- A simple system design.
- Water is already in the pipes when a sprinkler opens.
- Fewer dry-system parts to inspect and maintain.
- A good fit for heated areas where freezing is not a concern.
Wet-pipe systems still need regular inspection, testing and maintenance. They should not be treated as maintenance-free.
What Are the Downsides of a Wet Sprinkler System?
The biggest concern in Edmonton is freezing.
Water-filled sprinkler pipes must be protected from cold temperatures. Current fire protection guidance lists 4°C or 40°Fas the minimum temperature for areas with water-filled sprinkler piping.
This does not mean wet-pipe systems are a poor choice for all Edmonton buildings. Instead, consider this: Can all of the water-filled sprinkler pipes in this part of the building be protected from freezing?
Even a heated commercial building can have colder areas, such as service spaces or sections near the outside of the building. These areas may need extra attention when it comes to sprinkler freeze protection.
How Does a Dry-Pipe Sprinkler System Work?
A dry-pipe sprinkler system works differently from a wet-pipe system.
Instead of keeping water in the sprinkler pipes, a dry system normally holds pressurized air or nitrogen. The water stays behind a dry-pipe valve.
When a sprinkler opens:
- Air escapes from the open sprinkler.
- The pressure inside the pipes drops.
- The dry-pipe valve opens.
- Water enters the sprinkler pipes.
- The water travels to the open sprinkler and is released.
This extra step is one of the main differences between wet and dry sprinkler systems.
It is also important to remember that dry pipe does not mean dry chemical. A dry-pipe sprinkler system still uses water to control or suppress a fire.
Advantages of Dry-Pipe Sprinklers
Dry-pipe systems are mainly used in areas where water-filled pipes could freeze.
Depending on the building, this may include:
- Unheated or partly heated spaces.
- Loading or service areas.
- Parking areas.
- Exterior or semi-exterior spaces.
- Other areas that may be exposed to freezing temperatures.
The right system depends on the conditions in the building and how the fire protection system was designed.
What Are the Downsides of a Dry Sprinkler System?
Dry-pipe systems help protect sprinkler piping from freezing, but they are more complex than wet-pipe systems.
They have extra parts and conditions that need to be checked and maintained. These may include:
- The dry-pipe valve.
- Air or nitrogen pressure.
- Drainage points in the piping.
- Moisture that collects inside the system.
- Dry-system testing and operation.
There is also an extra step before water reaches the open sprinkler. The water must first enter the dry piping after the system operates.
Why Edmonton’s Climate Matters
As we’ve mentioned, Edmonton’s cold winters make freeze protection an important part of sprinkler system maintenance.
For wet-pipe systems, water stays in the pipes at all times. That means the piping must be kept warm enough to prevent freezing. But this does not mean every Edmonton building needs a dry-pipe system.
Instead, what matters is the temperature around the sprinkler piping. A heated commercial building may still have colder areas, such as loading spaces, parking areas or sections close to the exterior.
Ask yourself this: Can the sprinkler piping in this area of the building be protected from freezing?
If the answer is yes, a wet-pipe system may be suitable. If the area is exposed to freezing temperatures, a different approach may be needed.
Additionally, it is important to remember that building conditions can also change over time. Renovations, changes to heating or changes in how a space is used can affect the temperature around sprinkler piping.
If you are unsure whether part of your system is properly protected from freezing, have it assessed by a qualified fire protection professional.
Do Both Wet and Dry Sprinkler Systems Need Maintenance?
Yes. Both wet- and dry-pipe sprinkler systems need regular inspection, testing and maintenance.
Wet-pipe systems are generally simpler, but they still need to be checked for problems that could affect how the system works. In Edmonton, this also means making sure water-filled piping is properly protected from freezing.
Dry-pipe systems have some added maintenance needs because they use pressurized air or nitrogen and include extra components. These systems may require attention to:
- System air or nitrogen pressure.
- Dry-pipe valve condition.
- Drainage and low points in the piping.
- Moisture that has collected inside the system.
- Areas or components where water is still present.
The name “dry” can be misleading. Moisture can still collect inside dry sprinkler piping through condensation, testing or previous system operation. If that water settles in low points, it can become a problem during freezing weather.
The key takeaway is that neither system is maintenance-free. Wet and dry systems simply have different parts and conditions that need to be checked to make sure they continue to work as intended.
For more information, read our Expert Guide to Sprinkler System Inspections in Alberta.
When Should You Have Your Sprinkler System Assessed?
Your sprinkler system was designed around specific building conditions. If those conditions change, it may be time to have the system reassessed.
Contact a fire protection professional if:
- You are unsure whether water-filled piping is properly protected against freezing.
- The building’s heating conditions have changed.
- You have renovated, expanded or changed the use of a protected area.
- An inspection has identified sprinkler deficiencies.
- You notice signs of leaking or possible freeze-related damage.
- A dry system is experiencing pressure or operating issues.
- Required sprinkler inspection or testing is coming due.
Building systems do not operate in isolation. Changes to heating, building layout or space use can affect conditions around the fire sprinkler system as well.
Regular inspection and maintenance can help you identify those issues before they become larger problems.
Choose Karlen-Kada for Sprinkler Inspection, Maintenance and Repairs
Whether your Edmonton building uses wet-pipe sprinklers, dry-pipe sprinklers or a combination of systems, understanding what you have is only part of the job.
You also need to make sure the system continues to suit the conditions in your building and receives the inspection and maintenance it requires.
At Karlen-Kada, our fire suppression services include:
- Fire sprinkler inspections.
- Ongoing maintenance.
- Sprinkler deficiency repairs and replacements.
- System assessment and troubleshooting.
- Additional commercial fire suppression services.
Our team can help you understand your existing sprinkler system, identify deficiencies and determine what requires attention.
Learn more about our fire suppression services or contact Karlen-Kada to schedule sprinkler inspection, maintenance or repair in Edmonton.