Building on Sloping Sites in Mallorca
How Topography, Reference Ground Level, (Terreno de Referencia) and Access Conditions Shape the Planning
Sloping plots in Mallorca often offer the most spectacular sites: unobstructed sea views, impressive panoramas of the mountains, or idyllic valley landscapes.
However, they also present particular challenges for planning and licensing. It is crucial to understand the topography correctly, establish the terreno de referencia (reference ground level) appropriately, prepare an accurate 3D terrain model, design optimal access routes, and above all evaluate the advantages and disadvantages of this type of site.
- Understanding the Topography – The Basis of Any Project on a Sloping Plot
The topography of the site determines how the building is integrated into the terrain, how it is accessed, and how it connects to outdoor spaces.
The first step in sound planning is a detailed analysis of contour lines, sightlines, solar orientation, natural conditions, and the surrounding built environment. This avoids overlooking valuable potential and ensures a design that fits the site.
- What Is the Terreno de Referencia?
The terreno de referencia is the official ground level recognised by the town hall, from which all project levels and heights are defined.
Its determination may vary depending on the municipality, the applicable planning instrument, and any previous licences:
- In Palma, for example, the original natural ground level may be taken as the reference.
- In Calvià, a topographic survey from the time of the partial plan’s approval may be used, if the plot was undeveloped at that time.
In all cases, these data must always be cross-checked with an up-to-date survey. Discrepancies are common and must be identified and coordinated with the municipality before beginning the planning process.
The result is an official – often somewhat artificial – ground profile known as the terreno de referencia.
- Different Rules Depending on the Municipality
Based on the terreno de referencia, each municipality applies specific rules concerning height and construction, such as:
- How far the ground floor may rise above the terrain.
- How swimming pools, terraces and access ramps must be integrated into the topography.
- The depth and extent of underground spaces (garages, parking, basements).
- How gardens must be landscaped or terraced.
A detailed planning approach can make the decisive difference compared to a superficial one, particularly in high-value locations.
- Essential: A Precise 3D Terrain Model
To plan correctly on a sloping site, a precise 3D terrain model is indispensable, including both the immediate and wider surroundings.
Only with a realistic simulation of the overall situation is it possible to optimise building heights, views, solar exposure, access ramps, and landscape integration.
This model also serves as a basis for building permit applications and coordination with the authorities.
- Advantages and Disadvantages of Sloping Plots
Advantages:
- Spectacular views (of the sea, mountains, harbours, or cities).
- Greater privacy thanks to level differences.
- Attractive architectural opportunities with terraces, pools, and terraced landscaping.
Disadvantages:
- Higher construction costs due to earthworks, retaining walls, or additional safety measures.
- More complex planning processes.
- Permits dependent on official – often artificial – ground profiles.
- Access and construction logistics are more difficult, with higher demands for ramps and service roads.
- Planning Access and Entrance Areas
The way a sloping site is accessed has a decisive influence on both the project and its future usability:
- Access from below usually occupies the front part of the site and reduces usable garden or terrace space.
- Access from above is generally located at the back of the house and offers less space.
- Vehicle manoeuvrability must be ensured at the end of the ramp, in the garage or at the entrance.
- Ramps must be comfortable and safe, with adequate visibility and turning radii, including for service or maintenance vehicles.
- Design must allow ramps suitable even for low-clearance sports cars.
- Universal accessibility is essential for everyday use (shopping, household transport, mobility needs).
The arrangement of ramps, garages, parking areas, and entrances has a direct impact on the overall project concept.
- The Optimal Concept – Bringing All Factors Together
An experienced architect will integrate the real topography, the terreno de referencia, municipal regulations, access logistics, and the client’s requirements.
Only this combination achieves a balanced result between permitted building volume, comfort of use, and administrative feasibility, maximising the potential of the site.
Conclusion
When building on a sloping site, all relevant factors must be addressed from the outset and the project should be developed with the support of an architect who has local experience. This approach makes it possible to deliver projects that combine privileged views, comfort of use, and secure licensing procedures
