When Should You Use Flat Site Architecture?

Designing a scalable and future-ready intranet is a common challenge in SharePoint Online. One architectural approach that Microsoft strongly promotes today is flat site architecture.

Instead of building deep hierarchies with multiple sub-sites, flat architecture focuses on simplicity, flexibility, and long-term maintainability. But when does this approach actually make sense? Let’s break it down.

🏗️ What Is Flat Site Architecture?

Flat site architecture avoids nesting sites inside one another. Instead, it promotes creating independent site collections, each with its own purpose, permissions, and lifecycle.

These sites are then connected using Hub Sites, which provide:

Shared navigation
Common branding
Unified search experience

This model aligns perfectly with how Microsoft 365 is designed—modular, scalable, and cloud-first.

🚀 Key Benefits of Flat Site Architecture

Flat architecture isn’t just a design preference; it solves many real-world problems.

Simplified governance
Each site has its own permissions, retention, and ownership, making administration cleaner.
Better scalability
You can add new sites anytime without restructuring an existing hierarchy.
Improved navigation
Hub sites deliver a consistent user experience across related sites.
Enhanced security
Permissions are easier to manage at the site level rather than breaking inheritance.
Future-ready design
Fully aligned with Microsoft’s modern SharePoint roadmap.

📌 When Should You Use Flat Architecture?

Flat site architecture is especially useful in the following scenarios:

Large organizations
Departments need autonomy while still being connected.
Project-based work
Each project can have its own site without impacting others.
Enterprise intranets and digital workplaces
Consistent navigation and search across business units is critical.
Strict compliance and governance requirements
Different teams may need different retention or security policies.
Frequent organizational changes
Flat architecture adapts easily without breaking sub-site structures.

💡 Real-World Example

Imagine a global enterprise with departments like HR, Finance, IT, and Marketing.

Instead of creating all of them as sub-sites under one root site:

Each department gets its own site collection
All department sites are connected to a central hub site
Navigation, branding, and search are shared across the organization

This approach keeps each department independent while still feeling like part of a single intranet.

🔐 Best Practices for Flat Architecture

To get the most out of flat site architecture:

Use Hub Sites to logically group related sites
Define a clear navigation strategy early
Establish strong governance policies for site creation and ownership
Rely on metadata and Microsoft Search instead of folder-like sub-sites
Regularly review usage and archive inactive sites

Planning upfront prevents sprawl while maintaining flexibility.

🧠 Final Thoughts

Flat site architecture is no longer just a recommendation—it’s the modern standard for SharePoint Online.

By keeping sites independent yet connected through hubs and navigation, organizations gain:

Better scalability
Stronger governance
Improved user experience

If your organization values flexibility, performance, and long-term sustainability, flat site architecture is the right choice.

When should you use flat site architecture?