Home extensions: a resilient market in a struggling construction sector

The study conducted by MSI Reports, an independent French firm specializing in market research and sector analysis, highlights a resilient market, supported by strong structural trends: land pressure, changing lifestyles and the desire of households to optimize their existing housing.

A market that is holding up better than the new

The study highlights a contained decline in the lateral extension market of -3,9% in volume, with 19.308 projects completed, in a context marked by shrinking purchasing power and increasingly difficult access to mortgage loans. In comparison, the new single-family home construction market experienced a much sharper drop, reaching -26% between 2022 and 2023.

This resilience of the lateral extension market can be explained by a maintenance-renovation dynamic that is more resilient than new construction, the scarcity of land and the rise in real estate prices, which encourage expansion rather than relocation, and a growing attachment of the French to their homes and their quality of life.

Structural engines that remain powerful

The study highlights fundamental factors, independent of short-term construction cycles, that sustainably support the home extension market. The structural rise in property prices makes moving increasingly expensive, while land scarcity, exacerbated by the zero net land take (ZAN) objective, favors densification of existing housing rather than new construction.

Changes in lifestyles are also a major driver. The development of teleworking, the adaptation of housing to the needs of families, and the aging population are increasing the demand for additional, accessible, and functional spaces, particularly for aging in place.

Finally, in many situations, the extension also represents a lever for increasing property value, when the cost of the project remains lower than the value created on the real estate market.

A demanding market, requiring expertise and comprehensive support

The study also highlights the significant obstacles that structure the sector:

• The average cost of an extension is €60.000 to €80.000 for 20 to 30 m².
• administrative complexity (local urban plan, building permits, ABF [Architects of French Buildings])
• technical constraints related to intervention on existing structures
• stricter regulatory requirements with RE2020

In this context, the success of a project increasingly depends on comprehensive and secure project management, from design to completion.

Home extension: A new approach to adapting housing

For Cybel Extension, this study confirms a profound evolution in the housing market: the French tend to favour the optimization of their existing housing.

According to Vincent Noël, Managing Director of Cybel Extension: “The market fundamentals remain solid. Between land pressure, changing lifestyles, and an aging population, home extensions will become a major response to housing needs. Projects are more carefully considered, more demanding, and require comprehensive support. This is precisely the role of a general contractor specializing in extensions.”

Key figures from the study

• More than 21.800 lateral extension operations are planned for 2030 (compared to approximately 19.300 completed in 2025)
• Nearly 30 m²: average surface area of ​​a side extension
• Approximately €2.500/m²: average observed cost
• Over €60.000: average budget for an extension project

Illustrative image of the article via Depositphotos.com.