The Chennai Metropolitan Development Authority permits interconnection between flats in both HRB (High Rise Buildings) and NHRB (Non-High Rise Buildings), provided the approved planning and infrastructure norms are fully maintained.
Interconnection between flats generally involves combining adjacent residential units through:
- Internal staircases
- Connecting doorways
- Duplex-style layouts
- Structural openings between units
These modifications are increasingly common in
- premium residential developments where buyers seek larger living spaces or
- multi-generational housing arrangements.
- Family-owned adjoining flats
- Penthouse combinations
Why Parking Compliance Is Important
When two flats are merged:
- The built-up area effectively becomes a larger dwelling unit
- Parking demand may increase
- Occupancy pattern changes
Hence authorities insist that:
- Approved parking slots cannot be removed
- Driveways cannot be blocked
- Turning radius and circulation space must remain compliant
In many projects, buyers illegally:
- Convert stilt parking into rooms
- Block fire driveways
- Extend private areas into common spaces
These rules aim to prevent that require revised approval if the modifications alter sanctioned planning parameters.
Permitted in HRB & NHRB
NHRB (Non-High Rise Buildings)
Generally buildings below 18.3 m height.
HRB (High Rise Buildings)
Buildings above 18.3 m height requiring:
- Fire NOC
- Enhanced safety norms
- Additional setbacks
- Refuge area compliance
CMDA permits interconnection in both categories, but only when:
- Parking norms remain intact
- Fire escape access is unaffected
- Structural stability is maintained
- Common area encroachment does not occur
Restriction in Affordable Housing Projects
Interconnection between dwelling units is not permitted in affordable housing projects.
This restriction exists because:
- Such projects are approved based on fixed unit configurations
- Infrastructure calculations are linked to approved dwelling sizes
- Unit consolidation may violate affordability objectives and planning incentives
Why These Regulations Matter
These compliance norms help:
- Prevent unauthorized building alterations
- Preserve infrastructure efficiency
- Maintain emergency access and fire safety
- Protect approved parking layouts
- Ensure planned urban density standards
Non-compliance may result in:
- Enforcement notices
- Approval complications
- Occupancy-related issues
- Penalties under planning regulations
Relevant Verified.RealEstate Services
Builders, architects, and property owners can also utilize:
- Architectural Planning & Design Services
- Building Plan Preparation
- CMDA Approval Assistance
- Building Approval Verification
- Planning Compliance Review
- Property Legal Due Diligence
- Approved Plan Verification
Verified.RealEstate offers these services to assist builders to ensure flat interconnections comply with approved development and safety norms. and verify whether apartment modifications comply with approved development norms.