What drives the per-sq-ft price of terrace waterproofing, metal roofing, ACP/HPL cladding and exterior paint in India, and the GST, permission and society rules that apply.
A roof or façade quotation in India is usually written as a rate per square foot multiplied by an area, plus a few lump sums. The rate itself depends on the system (for example a polyurethane liquid membrane versus a cement-based coating, or a bare colour-coated sheet versus an insulated sandwich panel), the preparation the surface needs, the height and access, and whether old layers have to be removed first.
This section explains each system in turn and what makes its rate go up or down. It also covers the rules around the work: GST on works contracts and on materials after the rate changes that took effect on 22 September 2025, when you need building permission from the municipal body for an alteration, and what a housing society or RWA can require before you touch a terrace or the outside wall.
Start with the overview of roof and façade costs per sq ft. Every rupee figure on this site is an illustrative example to show how pricing works, not a market rate or a quote from any contractor. Rates vary a lot by city, season, building and material brand, so always compare at least two written quotations.
Costs, Systems and 2026 Rules
How ACP and exterior HPL cladding are priced per sq ft in India, why FR-core panels cost more, how the sub-frame changes the bill, and what fire rules to check.
Costs, Systems and 2026 Rules
When roof repairs, terrace sheds, cladding and façade changes need municipal building permission in India, what bye-laws usually exempt, and how to check.
Costs, Systems and 2026 Rules
How exterior wall painting is priced per sq ft in India, how cement paint, exterior emulsion, elastomeric and texture finishes differ, and what raises the bill.
Costs, Systems and 2026 Rules
How GST applies to roof and façade works contracts and to materials in India after the 22 September 2025 rate changes, with worked examples and invoice checks.
Costs, Systems and 2026 Rules
How colour-coated, Al-Zn coated and insulated sandwich panel roofs are priced per sq ft in India, what thickness and BIS marking mean, and when a new structure is needed.
Costs, Systems and 2026 Rules
How roof waterproofing, roof replacement, ACP/HPL cladding and exterior paint are priced per sq ft in India, what moves the rate, and the rules to check in 2026.
Costs, Systems and 2026 Rules
Who decides and who pays for terrace waterproofing, external painting and façade changes in Indian housing societies and apartment associations, and how to get approval.
Costs, Systems and 2026 Rules
How cementitious, acrylic, PU, bituminous membrane and brickbat coba terrace waterproofing are priced per sq ft in India, and which factors change the rate.
