Home Maintenance Budget Calculator
Compare the percentage-of-value and cost-per-area methods for budgeting home maintenance, adjusted for the age of the building.
💼 Are you a real estate agent or broker? Send this calculator to your buyers on your own branded listing page — every enquiry comes straight to your WhatsApp. Create free agent page →Maintenance is the cost owners consistently under-budget, because it arrives in irregular lumps rather than monthly bills. Nothing happens for three years and then the roof, the boiler and the windows all need attention in the same eighteen months.
Two rules of thumb are common — a percentage of value, and an amount per unit of floor area — and they frequently disagree. Taking the higher of the two and adjusting for the building's age is a more defensible budget than either alone.
The two methods
The percentage method takes a share of the property value, which scales with the market. The area method takes an amount per unit of floor area, which scales with the physical building. Take the higher, then add an uplift for each decade of age beyond twenty years, because older buildings need more work.
Worked example
A 400,000 property of 1,800 square feet: 1% of value is 4,000 and 1.50 per square foot is 2,700, so the base is 4,000. At 60 years old there are four decades beyond twenty, and at a 10% uplift per decade the budget becomes 5,600 a year, or about 467 a month.
Set it aside rather than budgeting it
The point of the figure is a separate account that accumulates. Maintenance arrives in lumps of several thousand, so a budget that exists only on paper is not a budget — it is a plan to borrow when the roof fails.
Turn a calculation into an enquiry
Buyers who run these numbers are ready to talk. Give every listing its own page with your photo, phone and WhatsApp on it — leads land straight on your phone.
Create your free property pageFrequently asked questions
Is one percent of value the right rule?
It is a starting point that works reasonably in mid-priced markets. Where property values are very high relative to construction costs it substantially overstates the need, and where values are low it understates it — which is why the area method is worth checking against.
Does a new build need less?
In the first years yes, and warranties often cover structural defects. Set aside anyway, because the reserve you build in the quiet decade is what pays for the expensive one, and nothing stays new.
What counts as maintenance rather than improvement?
Keeping the building in its current condition — repairs, servicing, replacing worn components. Adding something new or upgrading beyond the original standard is improvement, and it belongs in a separate budget with its own return calculation.