What are TAKS and KAKS, and how much can you build on a plot?

A land listing says "1,000 m²". Buyers often read that as "I can build 1,000 square metres". But that figure is the size of the plot; how much can be built on it is decided by two other numbers. Both appear on the zoning certificate, and together they define the plot's real capacity.

These two numbers — TAKS and KAKS — decide how much building a plot can carry. Any calculation made without them is an attempt to guess capacity from surface area alone, and that guess is usually wrong by a wide margin.

What is TAKS?

TAKS is the ground coverage ratio. It gives the share of the plot the building may occupy at ground level. With a TAKS of 0.40, the footprint can cover at most forty percent of the plot; the remaining sixty percent stays open as garden, parking and setback.

So TAKS tells you how wide the building may sit. On its own it says nothing about height.

What is KAKS (floor area ratio)?

KAKS — the floor area ratio — is total buildable area divided by plot area. It covers every storey added together. With a KAKS of 2.0, a 1,000 m² plot allows 2,000 m² of construction in total.

This is what you are actually buying: the floor area ratio is the building right the plot grants you. Two plots can be the same size and still grant completely different rights.

A worked example

Take a 1,000 m² plot with TAKS 0.40 and KAKS 2.0. Footprint is 0.40 × 1,000 = 400 m². Total buildable area is 2.0 × 1,000 = 2,000 m². Storey count is roughly total divided by footprint: 2,000 / 400 = 5.

Assuming an average gross unit of 120 m², that comes to 2,000 / 120 ≈ 16 units. This is a preliminary figure: setbacks, level differences, projection rules and parking regulations all pull it down.

Why listing area is not buildable area

Because a listing states the surface area, not the building right. Two neighbouring plots on the same street can carry ratios of 0.5 and 2.0 — a fourfold difference that never appears in the listing text.

• Plot area: the surface area on the title deed. Fixed.
• Footprint: TAKS × plot area. What the building covers at ground level.
• Total buildable area: KAKS × plot area. The right you are actually buying.
• Storey count: total ÷ footprint. A height limit may restrict it further.

Exempt areas and setbacks

Not all of the ratio on paper turns into sellable flats. Regulations exempt certain areas from the count: shared spaces up to a limit, shelters, parking and technical volumes are the main ones. This can push the figure both ways — an exempt area gives you extra built space, while the same regulation imposes mandatory parking.

Setbacks cut the footprint directly. Once front, side and rear distances are subtracted, what remains may be smaller than TAKS allows. On a narrow, deep plot the gap is stark: the certificate may say 0.40 while the geometry forces 0.30.

So the footprint should be computed twice: once from the ratio, once from the plot's actual shape. The smaller figure is the real one.

How a height limit cuts the storey count

The storey count derived from the ratio is a result, not a ceiling. The zoning plan separately sets a maximum height or storey count. If the ratio suggests five storeys but the plan caps it at three, three wins — and you cannot use the full ratio without widening the footprint.

The reverse happens too: with a free height but a low TAKS, the building comes out narrow and tall. The same ratio produces two very different architectural outcomes. Which one suits depends on the plot's position, its neighbours and the view.

How do slope and level affect this?

TAKS and KAKS are flat geometry; they know nothing about the terrain. But on a sloping plot the same ratio costs more to build. Excavation grows, retaining walls enter the picture, and in some cases the level difference earns a basement storey and improves the maths.

That is why the ratio should be read alongside the terrain's elevation model. Two plots may share the same ratio; if one is flat and the other slopes at fifteen percent, their costs will not match.

Comparing two plots by ratio

Say you are looking at two plots. The first is 800 m² with a ratio of 1.5. The second is 1,200 m² with a ratio of 0.8. In the listing the second looks bigger and probably costs more. But look at the building right: 1,200 m² versus 960 m². The smaller plot grants more.

The way to compare properly is to divide the asking price by the building right rather than by the surface area. Not cost per square metre of land, but cost per buildable square metre. Only then do two plots speak in the same unit.

Add slope, setbacks and the height limit to that calculation and the picture sometimes reverses entirely. The plot that looked cheap can turn out expensive because its usable right is low.

Municipal certificate versus preliminary calculation

The only binding document is the official zoning certificate issued by the municipality. TAKS, KAKS, height, setbacks and any special restrictions are written there. A preliminary calculation does not replace it.

A preliminary calculation does something else: it shows the order of magnitude before you commit. Knowing whether a plot grants 2,000 m² or 500 m² tells you whether it is worth visiting at all. The official document comes after that step.

How Parselo runs this calculation

The Urban module takes your TAKS and KAKS values and computes the building envelope from the plot's official boundary: footprint, total buildable area, approximate storey count and number of units. It then layers the terrain's elevation model on top and derives an excavation estimate from slope and level difference.

The output is a preliminary feasibility and the report says so plainly: it does not replace the official zoning certificate, an approved architectural project or a geotechnical survey. What it computes is a square-metre right — not a valuation, and certainly not a price estimate.

If you want to try a plot's building envelope with your own figures, that is exactly what the Urban module is for.