High-pile storage requirements could influence any of the following: Types of commodities to be stored may be limited based on fire protection system design and storage height per type of commodity as allowed by fire code. Type of decking on load levels.  Typically requires 50% or greater opening to allow water to pass through. Flue spacing requirements.  Both longitudinal and transverse flue spaces may need to be kept clear, allowing water from fire protection system direct access to stored product.