Shoring of common areas in inhabited heritage collective housing in Lima’s Historic Centre: foundations and methodology of preventive intervention

Abstract

Lima’s Historic Centre contains a significant network of inhabited heritage collective housing —buildings declared as monuments or of monumental value— whose residential units are organised around common areas: courtyards, cantilevered galleries, corridors and walkways serving as the only evacuation route in emergencies. These spaces exist within a responsibility gap: neither street nor private dwelling, generating progressive deterioration that transforms them into the structurally most vulnerable point of the ensemble. The traditional adobe and quincha system represents a repository of technological knowledge coherent with Lima’s seismic conditions, whose preservation depends on the state of its common areas.

This article presents the preventive intervention methodology through shoring of common areas, developed by PROLIMA and adapted to inhabited heritage collective housing. Timber shoring is analysed as appropriate technology: technically grounded, low-cost, compatible with traditional construction culture and reversible. The methodology, formalised in Procedure N° M.01.01-P001-2025-MML, reduces collapse risk without displacing residents. Two cases are examined: Jr. Carlos Zavala (Jr. Sandia 229 / Jr. Leticia 501-519), with an exterior cantilevered gallery, and the Antiguo Molino de Santa Clara (Jr. Ancash 980-998 / Jr. Jauja 434-498), with a semicircular interior courtyard.