Some codes have 2 parts (e.g. 6.1) or 4 parts (e.g. 18.1.3.2) — deeper = more specific variant

These are CPWD DSR 2021 base rates for Delhi — the government's reference book, not today's market in your city. CPWD itself applies a quarterly Cost Index on top of these base rates for each station, and 2026 market rates typically run above the 2021 base.

How to use them well: treat DSR as the structure (what an item includes, its unit, its labour+material breakup) and negotiate the percentage above DSR, not the absolute number. For your own pricing, open BOQ Builder → 🔧 Rate Library and punch in your local cement / sand / mason rates — every analysis-backed item recalculates from your basic rates, exactly how a contractor builds a quote.