Dry Pipe and Antifreeze Sprinkler Systems

Dry Pipe Systems

In dry pipe systems, the pipe network is held under air or nitrogen pressure; only once a sprinkler head opens does a dry pipe alarm valve release the flow of water. This design inherently delays the start of water discharge compared with a wet pipe system, which must be accounted for in pipe network length and detection logic.

Antifreeze Solutions

In wet pipe systems of limited extent, an approved glycol-based or other antifreeze solution can be added to the water to protect smaller freeze-exposed sections without a separate dry pipe system. Non-approved or incorrectly dosed additives change the extinguishing performance and flammability of the solution and represent a frequently underestimated risk.

Insurance Relevance

Freeze damage to sprinkler systems is a recurring cause of loss during cold periods. Correctly designed and regularly tested dry pipe or antifreeze systems prevent both a failure of the extinguishing system and water damage from burst pipework.