1 Concrete5 v5.6 is a legacy system — not just an old version
Concrete5 5.6 and below belong to a completely different generation of the CMS.
When Concrete5 moved to v5.7 (later rebranded as ConcreteCMS), the core was rewritten from scratch:
- New architecture (MVC, Symfony components)
- New file system
- New database structure
- New permission model
- New block & package system
There is no direct or automated upgrade path from 5.6 → latest ConcreteCMS.
This is the single biggest blocker.
Upgrading 5.6 is not an “upgrade” — it’s effectively a rebuild + migration.
2 Themes, blocks, and add-ons from 5.6 are mostly incompatible
Most 5.6 sites rely on:
- Custom themes
- Custom blocks
- Old marketplace add-ons
These were built using:
- Deprecated PHP practices
- Legacy Concrete5 APIs
- Hard-coded helpers and global variables
In modern ConcreteCMS:
- Those APIs no longer exist
- Blocks must be rewritten
- Themes must be rebuilt using modern standards
For many sites, 80–100% of custom code must be rewritten, not “fixed”.
This is where cost and effort increase sharply.
3 Content migration is manual and risky
Concrete5 5.6 content is stored very differently:
- Page types vs page templates
- Attribute handling
- Block storage
- File manager structure
Migration usually involves:
- Exporting content from 5.6
- Mapping page structures manually
- Rebuilding page types
- Re-adding blocks or recreating layouts
- Manually validating thousands of pages (on larger sites)
For content-heavy sites, migration is time-consuming and error-prone.
4 Server & PHP compatibility gap
Concrete5 5.6:
- Requires very old PHP versions
- Often runs on PHP 5.3–5.6
Latest ConcreteCMS:
- Requires modern PHP (7.4–8.x)
- Modern MySQL/MariaDB
- Stronger security defaults
Upgrading often forces:
- Hosting migration
- PHP upgrades
- Database charset changes
- Fixing legacy hosting configurations
Some sites are literally held together by old servers that can’t be touched.
5 Cost vs perceived benefit
For many business owners:
- “The site works”
- “It’s ranking fine”
- “No one touches it daily”
From their point of view:
- Spending money on a rebuild feels unnecessary
- They don’t see the technical risk
- ROI is unclear unless redesign or new features are planned
So the upgrade keeps getting postponed.
Why people still run websites on Concrete5 v5.6
1 “If it ain’t broke, don’t fix it” mentality
Many 5.6 sites:
- Are brochure websites
- Rarely updated
- Still generate leads or traffic
Owners prefer stability over change — even if it’s risky long-term.
2 Fear of breaking SEO or content
Older sites often have:
- Years of SEO authority
- Thousands of indexed URLs
- Custom URL structures
Owners fear:
- Ranking drops
- URL mismatches
- Lost content
- Broken forms
Without an experienced migration strategy, that fear is valid.
3 Lack of experienced Concrete5 migration developers
This is huge.
Most modern developers:
- Never worked with 5.6
- Don’t understand its internals
- Underestimate migration complexity
Result:
- Bad upgrade attempts
- Broken admin areas
- Lost data
- Abandoned projects
So site owners stick with what they know.
4 Security risk is underestimated
Concrete5 5.6:
- No longer receives security patches
- Runs on unsupported PHP
- Has known vulnerabilities
But unless the site is hacked, owners don’t feel urgency.
Security problems are invisible… until they’re not.
The reality (important takeaway)
Upgrading from Concrete5 5.6 → latest ConcreteCMS is:
❌ Not an upgrade
❌ Not automatic
❌ Not cheap
✅ It is a controlled rebuild with content migration
✅ Best done by someone who has worked with both 5.6 and modern ConcreteCMS
When upgrading does make sense
- PHP version must be upgraded
- Hosting provider drops old PHP
- Site needs redesign or new features
- SEO performance is declining
- Security/compliance becomes critical
In those cases, migration becomes unavoidable — and smart.