Cost Guide · 4 min read · 1 October 2026

12 Hidden Costs in House Construction Nobody Tells You About (Bangalore)

By Darshan H, Matrix Realty

Most budget overruns don’t come from the construction rate — they come from items that were never in it. Here are the twelve costs to put in your budget from day one, so the final number doesn’t surprise you.

The twelve costs

1. Soil test and survey — small but essential. See soil test.
2. Architect and structural design fees — if not part of your builder’s package.
3. Plan approval fees — calculated by the authority. See plan approval.
4. Khata work — e-Khata corrections or B-to-A conversion (5% of guidance value).
5. Temporary power and water during construction.
6. Compound wall and gate — see compound wall cost.
7. Sump and overhead tank — sized for your family and tenants.
8. Borewell — depth and yield vary a lot across Bangalore.
9. Rainwater harvesting — required for new buildings in Bengaluru above specified site sizes.
10. BESCOM and BWSSB connections — permanent power, water and sewer connection charges.
11. Interiors — wardrobes, modular kitchen, false ceiling, lights and fans.
12. GST and contingency — keep 5–10% for price changes and small upgrades.

How to budget

A simple rule: construction cost + 10–15% covers most of items 1–10 on a typical 30x40 G+1 home; interiors are separate and depend entirely on your choices.

How to avoid surprises

• Ask every builder for a written list of exclusions.
• Get allowances in ₹ per sq ft or per piece for tiles and fittings.
• Price and sign every change before it is done.