Vernacular architecture embodies a lasting connection between communities, climates, and topographic landscapes, providing basic shelter needs for centuries. Adopting Montesinho Natural Park as a case study, this paper explores the essence of vernacular architecture, highlighting its adaptation and dynamic relationships with local climates, geographical features, and scarce resources. This paper firstly provides a quantitative characterisation of residential vernacular building typologies in several villages of the park based on field-collected data, using photography and videography for data reliability. The building typologies were then categorised according to their prominent architectural features, prioritising the access to the upper floor and door’s relative location and their integration within the landscape’s topography. The collected data were analysed by averaging each typology percentage across the villages and calculating dependency probabilities between each typology and the villages, aiming to identify the most frequent typologies and their dependency relationships with villages. This paper’s outcome entails the Protruding Staircase typology as the most common typology in the selected villages. Despite modern interventions, traditional features endure, emphasising practicality and resource efficiency. Among them, several bioclimatic strategies were identified and analysed qualitatively based on their potential contribution to energy efficiency and savings, highlighting their relationships with the local context and the typologies presented. The findings are important in supporting decision-making related to vernacular heritage in Northeastern Portugal. The bioclimatic construction strategies identified may be used as preliminary references to incorporate into rehabilitation projects and sustainable architecture practices, enhancing inhabitants’ thermal comfort and living conditions.

As global climate volatility intensifies, the built environment requires passive capacity to decouple habitability from external extremes. While vernacular architecture is a cited bioclimatic model, research often lacks long-term quantitative validation. This study addresses this gap through a multiscale framework applied to Montesinho Natural Park, Portugal. Integrating a typological survey with a one-year in situ monitoring campaign (2024–2025), the study utilises Python-based data processing to calculate statistical cross-correlations and benchmarks thermal resilience against the Portuguese Adaptive Comfort Model. Results substantiate a “Hierarchy of Filtration”: (1) Geological Scale: Location correlates statistically with lithological availability; (2) Settlement Scale: Topographical shielding suppresses the Diurnal Temperature Range (DTR) by 20.5%; (3) Envelope Scale: Traditional Stone-on-Earth assemblies exhibit a 16.5 h thermal lag, while vertical functional stratification dampens 47% of external annual temperature extremes. The study concludes that retrofitting must shift to “Balancing Inertia and Connectivity”. This approach mitigates the ‘maladaptation’ risks observed in modern lightweight interventions, providing an empirical template for passive thermal resilience applicable to resilient urban design in a warming climate.

This study evaluates the winter thermal performance of a traditional granite masonry dwelling in Pinheiro Novo village, located within Portugal’s Montesinho Natural Park (MNP). The research addresses critical gaps in understanding vernacular building performance under extreme cold conditions, where passive strategies often fall short of modern comfort expectations. Through a year-long environmental monitoring campaign, indoor and outdoor temperatures were recorded at 30-minute intervals across key functional spaces, including the kitchen, bedroom, and guestroom. Results reveal that the 80 cm granite walls provide moderate thermal stability, with the bedroom averaging 11.6°C (range: 7.7–19.8°C) in winter and 3.7°C warmer than unheated zone guestroom but still significantly below adaptive comfort thresholds. The wood-burning stove generated localised warmth (peaking at 23.1°C in the kitchen), but heat distribution was ineffective, with adjacent spaces remaining cold due to poor thermal transfer and envelope losses. The study highlights the limitations of traditional passive strategies in maintaining winter comfort, particularly in unheated rooms like the guestroom (7.9°C average). While bioclimatic features such as thermal mass and compact layouts offer some benefits, they are insufficient against prolonged cold. Future research should validate these interventions through monitored case studies and integrate empirical data with indigenous knowledge for culturally sensitive solutions. This work contributes to sustainable heritage preservation by advocating for a balanced approach that respects vernacular wisdom while addressing contemporary needs. It underscores the importance of interdisciplinary collaboration in developing retrofit strategies that are both energy efficient and culturally appropriate, ensuring the resilience of traditional architecture in a changing climate.

This study highlights thermal underperformance in key spaces of a vernacular granite masonry building in Portugal, where winter monitoring revealed critically low air temperatures (9.5 °C in the bedroom at 06h30), failing adaptive comfort standards despite passive strategies like thick walls and wood stoves. A localised analysis of external walls and slate roofs evaluates agglomerated cork insulation (5 cm & 10 cm) through simplified thermal calculations. Results show 10 cm cork reduces wall U-values by 82 % (0.387 W/m²·K) and roof U-values by 93 % (0.439 W/m²·K), while 5 cm balances insulation (0.658 W/m²·K) with retained thermal mass. Long-term data correlates inherent passive designs, namely thermal mass from granite walls and shared party walls, with limited buffering capacity during extreme cold, necessitating targeted retrofitting. Despite moderate solar gains and stove heating, the building’s thermal inertia proves insufficient without intervention. The findings reveal context-sensitive retrofitting: thicker cork for stable climates, moderate layers for regions requiring thermal mass. By aligning cork insulation with traditional strategies, this approach enhances energy efficiency without compromising heritage integrity, supporting SDG 11. Future work should integrate dynamic simulations to optimise solutions for vernacular architecture.

The retrofit of vernacular building stock is essential for sustainability, yet standardised solutions often fail to address the typological diversity of mountain regions. Rather than proposing novel designs, this research provides an empirical evaluation of two prevalent, real-world intervention archetypes compared to a baseline scenario corresponding to a building with its original solutions in the Montesinho Natural Park: a non-retrofitted vernacular dwelling (Pathway A), a modern reconstruction using industrial materials (Pathway B), and a sensitive thermal adaptation (Pathway C). Thermal comfort was assessed using the Portuguese adaptive model, contextualised by long-term hygrothermal monitoring and occupancy profiles. Results reveal a critical divergence: the non-retrofitted baseline confirms severe winter discomfort; however, improving this comfort is vital to prevent building abandonment and ensure long-term maintenance. The modern reconstruction (Pathway B)—utilising an internal XPS and plasterboard lining—achieves a rapid thermal response suitable for intermittent use, but represents a “linear substitution”. By discarding the original structural solutions, it fails to extend their lifespan and instead generates construction and demolition waste. Conversely, the sensitive rehabilitation (Pathway C) preserves the granite shell (structural circularity), successfully extending the amortisation of the building’s existing embodied impacts. However, it risks summer overheating as the non-reversible internal insulation thermally decouples the envelope from the dwelling volume. The findings highlight that sustainable interventions must balance occupant comfort with respect for heritage, prioritising the maintenance of differentiating characteristics and the reversibility of construction works over standardised replacements