Fire Safety at Masterplan Stage: Access, Water and Separation

At masterplan stage the roads, the plots and the infrastructure networks are drawn before any building is designed. At that same moment, safety decisions get locked in that are hard to undo: the width of the road a fire appliance will use, the capacity of the water network, the distance between buildings, and where hazardous uses sit. Fixing these after the masterplan is approved means compensating inside each building separately, at a much higher cost.

This article walks through what to check at site level before the plan is fixed, and what belongs in the plot conditions before land is handed to developers.

1. Fire apparatus access

Access is not simply "a road near the building". It is a set of linked requirements:

• Road width: international appendices use a common minimum of about 6 m, rising to about 8 m where fire hydrants sit on the road or where aerial apparatus access is required.
• Dead ends: dead-end roads longer than roughly 46 m need an approved turnaround — a cul-de-sac, a hammerhead or a Y.
• Loads and turning radii: pavements, bridges and podium slabs have to carry a loaded appliance, and turning radii have to suit it.
• Approach distance: where the road sits relative to the facade decides whether an aerial appliance can be used, and trees, power lines, canopies and fencing all affect it.
• Gates and barriers: gated communities need an agreed arrangement for opening gates in an emergency, not an operational decision left to a guard.

2. Firefighting water

A network sized for domestic demand alone is not enough for firefighting. What has to be settled at site level:

• The required flow for each area, which depends on the expected building areas, the construction type and whether buildings are sprinklered. Published values in the international references range from a few hundred to several thousand gallons per minute.
• The duration and the source: site tanks and pump stations, not the municipal network alone.
• Hydrant distribution: the reference tables tie the number of hydrants, their average spacing and the maximum distance from a building to the required flow; the higher the flow, the tighter the spacing. Spacing is usually relaxed where buildings are sprinklered, and tightened on dead-end streets.
• Pressure and looping: a looped network with isolation valves keeps service during faults and maintenance, which a branched network cannot do.

These values come from the international appendices the Saudi code builds on. What governs your project is the current edition of the code and the Civil Defense requirements, fixed in the design basis before any calculation.

3. Separation distances and hazardous uses

• Separation between buildings limits fire spread by radiation, and drives facade opening ratios and fire resistance requirements.
• Hazardous uses — warehouses, fuel stations, gas tanks, power plants and data centres — are placed early, away from residential clusters and the main escape routes.
• Places of assembly and emergency assembly points are set at site level, not building by building in isolation.

4. Response coverage across the site

On large sites the question becomes: how long does the fire service take to reach the furthest point? The answer depends on the number of entrances, whether an alternative route exists when one is closed, road gradients, and the distance from the nearest fire station. The result may require extra protection inside buildings, or a fire station within the site on the largest developments.

5. Plot conditions and construction phasing

On multi-developer projects the most valuable output is what gets written into the plot conditions before handover:

• The access available to each plot: the width of the adjoining road, whether aerial access is possible, and the approach points.
• The water capacity and connection points allocated to the plot, and who pays to reinforce the network if a building exceeds the assumptions.
• The height and area limits the safety assumptions were based on, and what triggers a new study.
• Responsibilities during the transition: temporary roads during construction, the temporary water source, and securing open sites.

Common mistakes

• Sizing the water network for domestic demand, then discovering the shortfall at the first large building.
• Long dead-end roads with no turnaround, which appear once the plots are subdivided.
• Hydrants that end up inside private plots or behind walls.
• Gates, speed humps and barriers that a loaded appliance cannot pass.
• Deferring the sprinkler decision, although it directly affects water demand and spacing.
• Leaving the operation and maintenance of shared firefighting tanks and pump stations unassigned.

How Three Edges can help

We provide fire safety review at masterplan level, including:

• Checking access, water, separation and response coverage across the whole site.
• Drafting the safety requirements that go into the plot conditions and the phasing.
• Tying those to the fire and life safety strategy of each building and to code compliance.
• Coordinating with the authorities to agree the principles before the plan is fixed.

Frequently asked questions

Are the access and water appendices mandatory?

Appendices in the international references become mandatory when the adopting authority adopts them. For projects in the Kingdom what governs is the current edition of the Saudi code and the Civil Defense requirements, fixed in the design basis before any calculation.

Who is responsible for firefighting water on large masterplans?

Usually the infrastructure developer, but in practice responsibility is shared with the plot developers. It is better written into the plot conditions than negotiated later.

Do sprinklers reduce the external water requirement?

Often yes: the references allow some requirements to be relaxed in fully sprinklered buildings. The amount is set by the adopted reference, and should not be assumed in advance.

When should the masterplan review start?

Before the road network and the plot subdivision are fixed. After that, the remaining options are the expensive ones: reinforcing networks, adding protection inside buildings, or changing uses.

Do you have a masterplan in preparation, or plots about to be handed to developers? Request a masterplan review before the roads and networks are fixed.

References

• Saudi Fire Code SBC 801 — Saudi Building Code portal
• International Fire Code — appendices on fire flow, hydrant distribution and fire apparatus access roads
• NFPA 1: Fire Code — access and water supply requirements
• Performance-based design for cases where the requirements cannot be applied literally