Type "house renovation cost" and within seconds you'll find a free tool that hands you an amount. It's fast, it's no-strings, and honestly it's useful at the very start of a project. But the moment it comes to financing those works, presenting the figure to a bank, or setting a budget you're staking your savings on, that number quickly shows its limits. The real question isn't "free or paid", it's: what kind of figure do you need?
What a free calculator does very well
Let's be fair: a free online calculator has real value. By filling in three or four fields — floor area, property type, scope of works — you instantly get a ballpark. That's enough to know whether a project runs into tens of thousands of euros or hundreds, to choose between two scenarios, or to decide whether the idea is worth taking further. As a first compass, it's exactly what you need.
But that strength is also its limit. A free tool almost always rests on national averages: a generic, undated price per square metre, identical for a 1930s Brussels apartment and a recent build on the outskirts. It knows nothing about your property, and doesn't claim to. The figure is indicative — and it will stay that way.
The four things €29 adds
When the project gets serious, four elements tip a figure from indicative estimate to a document that holds up. None of them is within reach of a purely automatic, free tool.
1. Calibration on the ABEX index
Rather than a fixed price per square metre, each item is keyed to the current ABEX index, the official Belgian construction-cost index, revised twice a year. The figure therefore reflects the real cost of the building at the moment you ask for it, not an average from two years ago. That's the difference between a dated estimate and a price with no age.
2. An expert review
A qualified human reviews every report before it reaches you. They catch what a machine lets through: a forgotten item, an unrealistic scope of works, a regional quirk. That step turns a calculation into an estimate that someone puts their responsibility behind. We go into this work in why we keep an expert in the loop on every report.
3. Matched regional grants
The gross figure doesn't tell you what you'll actually pay. A serious report matches the regional grants your works qualify for — Renolution in Brussels, Mijn VerbouwPremie in Flanders, Primes Habitation in Wallonia — and deducts them to surface the amount left to finance. A free calculator stops at the gross cost; it leaves you alone with the question of grants.
4. A bank-ready PDF
This is probably the most concrete difference. The report is a dated document, itemised line by line, stating a company number and signed — exactly what a bank looks for in a renovation file. A screenshot of a free calculator doesn't make it across a credit officer's desk. A Qote PDF does.
When each has its place
There's no wrong option, only the right tool at the right moment. Use a free calculator to explore, rough things out, compare ideas while nothing is committed. Move to a Qote report the moment you need to set a firm budget, apply for a loan, sell or buy on the basis of a works cost, or simply stop navigating by guesswork. For €29, you replace a ballpark with a reliable online renovation estimate — calibrated, reviewed, grants deducted, and recognised by the people who matter.
Frequently asked questions
Is a free renovation calculator reliable?
It gives a useful ballpark for a first idea, but it stays indicative. It relies on undated national averages, takes no account of the specifics of your property, and produces no document you can defend before a bank, notary or insurer.
What does a reliable estimate add over a free one?
It calibrates each item on the current ABEX index, is reviewed by an expert, matches regional grants to compute the amount left to finance, and comes as a dated, itemised PDF that states a company number. That's the difference between an indicative figure and a document that holds up.
Why pay €29 if a free tool already gives a figure?
Because the two serve different purposes. The free one answers "roughly how much?". The €29 answers "how much exactly, and with a document my bank accepts?". The moment you need to finance or defend the works, a ballpark is no longer enough.
From ballpark to document
Answer a few questions, the engine calibrates 1,240 line items on the current ABEX index, an expert reviews and grants are deducted. Twenty minutes, no site visit, from €29.