Plot guide: cadastral reference, setbacks, coverage, floor-area ratio and sun

The concepts you need to know what you can build on a plot in Spain, and how to see them in Mi Parcelita.

The cadastral reference (referencia catastral)

It is the official identifier of every property in the Spanish Cadastre. A plot's reference has 14 characters (for example 3294035QA5239S); a property within it has 20: the plot's 14, 4 numbering the property and 2 check characters.

You'll find it on the IBI property-tax bill, the deeds or a land-registry extract, and on the Catastro's website (sedecatastro.gob.es) by address or on the map. With it, Mi Parcelita downloads the plot's official outline, area and address and, if you want, its buildings.

Setback (retranqueo)

The minimum distance buildings must keep from the plot boundaries: the street, the neighbours or both. Each municipality sets it in its planning rules, and it may differ per boundary, for pools or for outbuildings.

In Mi Parcelita you enter the setback in metres and it is drawn inside the plot. Houses, garages and other roofed buildings must stay within it; pools only if you switch that on. Anything that breaks it turns red.

Coverage (ocupación)

The share of the plot covered by buildings in plan: the built footprint divided by the plot area. 30% coverage on a 600 m² plot allows a 180 m² footprint.

Mi Parcelita counts the footprint of the roofed buildings you place and of the existing buildings recorded by the Catastro.

Floor-area ratio (edificabilidad)

The total floor area allowed, adding up every storey, usually given as a ratio of m² of floor per m² of land. At 0.4 m²/m² on a 600 m² plot you can build 240 m², for example 120 m² on each of two floors.

Mi Parcelita multiplies each building's footprint by its floors (carports and pergolas at 50%), adds the official floor area of what already exists and compares the total with the maximum you enter. You can also set maximum coverage, height and floors.

Sun: facing the house and placing the pool

In Spain a south-facing façade gets sun all year, and in winter, with the sun low, it reaches deep into the rooms; east and west façades get the low morning and evening sun. What really decides it, though, is shade: from your own house, trees, neighbours and mountains.

Mi Parcelita computes the sun's position for your plot on any date and time and draws the shadows in 3D. The sun-hours map shows how many hours of direct sun every part of the plot gets in a day: look at a summer day for the pool and a winter day for the garden or the main façade.

Slope

With the IGN's MDT05 terrain model, Mi Parcelita shows the plot's elevation and average slope, slope bands and contour lines, and sets each building on the ground with a plinth on the downhill side.

This guide is for information only. The rules that apply to your plot are those of your municipality's current planning: check them with the town hall or a professional.