Sinking Fund and Repair Fund Calculator for Housing Societies

Every building needs big repairs eventually: external painting, waterproofing, plumbing risers, lift replacement, structural repairs. A sinking fund (and, in many societies, a separate repair and maintenance fund) spreads that cost over years so members are not hit with a sudden special levy. The difficult question is how much to collect.

Housing bodies in India are registered under different laws: co-operative housing societies under the state's co-operative societies Act and bye-laws; many RWAs under the Societies Registration Act, 1860 as applied in the state; apartment owners' associations under a state apartment ownership Act; a few as section 8 companies. Periods, quorums and rates differ — the workbook keeps them as settings for that reason.

Method 1: the rule in your bye-laws

Some bye-laws set a minimum contribution as a percentage of construction cost per year. For example, the model bye-laws for co-operative housing societies in Maharashtra refer to a sinking fund of at least 0.25% of construction cost a year and a repair and maintenance fund of 0.75% a year. Other states, and RWAs under other laws, have different rules or none. The calculator uses these figures only as illustrative defaults — replace them with your own bye-law rates, and use the construction cost your bye-laws refer to.

Method 2: plan the works

A rule-based contribution may be too little or too much for your building. The second method lists the major works you expect, with today's estimate and the year each falls due, inflates each estimate to that year, and checks whether the fund will have enough.

1. List the works with your engineer or facility manager: what, when, and an estimate at today's prices (a contractor quote or the engineer's estimate).
2. Set a cost-inflation assumption.
3. Enter today's fund balance and the return you expect on it (for example, fixed-deposit interest after any tax).
4. The projection shows, for 15 years, the opening balance, contributions, return, works paid and closing balance — and flags any year where the fund goes negative.

Testing a contribution

Enter a monthly contribution per flat on the settings sheet to test it; leave it at zero to use the bye-law rule. Adjust until no year shows a shortfall, and look at the margin left after the largest job — lift replacement and structural repairs are often the ones that break the plan.

Governance points

• Keep the fund in a separate bank account or deposits, as resolved by the general body.
• Use it only for the purposes your bye-laws or resolution allow (major repairs, not routine maintenance).
• Record every withdrawal with the resolution that approved it.
• Review the works list and estimates every year or two; costs and the building's condition change.

Tax and GST

Whether contributions to a sinking fund attract GST depends on how your society is set up and the per-member limits — treat them consistently with your maintenance billing and get advice if your monthly contributions are close to the exemption limit. Interest earned on the fund's deposits is generally taxable income of the society subject to available deductions; confirm with your tax adviser.

Present it to members

Members accept a higher contribution more readily when they see the works list, the estimates and the projection. Attach the projection to the AGM notice when you propose a change (see our AGM notice and minutes checklist).

Worked example (illustrative)

A 120-flat society with a construction cost of ₹15 crore, a fund of ₹25 lakh, and three planned works — external painting in 2029 (₹45 lakh today), terrace waterproofing in 2031 (₹20 lakh) and lift replacement in 2036 (₹60 lakh) — runs the projection at 6% cost inflation and 6.5% return. Under a 0.25% rule (₹3.75 lakh a year) the fund turns negative in 2029 and never recovers. Testing ₹1,000 per flat per month (₹14.4 lakh a year) keeps the fund positive in every year — the thinnest points are after the 2029 painting and the 2036 lift replacement, at roughly ₹42–44 lakh. The committee proposes ₹1,000 per flat and a review of the estimates in two years.

Common mistakes

• Treating the bye-law minimum as the right amount.
• Estimates at today's prices for works ten years away.
• Using the fund for routine maintenance.
• Not reviewing the works list as the building ages.