Risk Engineering

Outdoor Storage

Expert-reviewed Updated: 2026-09-01 Expert-reviewed: 2026-09-04 (Guido Hesse, Hesse Group Holding AG) Version 0.1.0

Outdoor storage refers to storing goods, raw materials or empty containers outside enclosed buildings, where the absence of sprinkler protection must be offset by generous separation distances, vegetation control and access security.

Hazard picture

Goods stored outdoors without automatic suppression rely on adequate separation from buildings and from other storage piles to prevent fire spread through radiant heat; at the same time, the lack of weather protection exposes certain materials to yellowing, icing or moisture ingress. Outdoor storage areas are also more accessible than indoor storage, increasing the risk of arson and theft, particularly outside operating hours.

Protection measures

Key measures are minimum separation distances between individual storage piles and to buildings, determined by stack height, combustibility of the goods and the wall construction of the adjacent building; vegetation-free security strips also prevent dry vegetation from acting as an ignition bridge. Good lighting, fencing and, where appropriate, video surveillance reduce the risk of unauthorised access, while clear operational rules prevent outdoor areas from becoming an uncontrolled overflow store for goods they were never designed to hold.

Insurance relevance

Because outdoor storage areas are rarely central to the original fire protection design and tend to expand over time, uncontrolled growth of outdoor storage is among the most frequent deviations identified during risk surveys. Insurers therefore assess documented separation and access control concepts for outdoor areas as a distinct component of risk quality, independent of the protection level of the buildings themselves.

Standards and codes

  • NFPA 1 – Fire Code