Post-Insulating External Walls: Inside Or Outside?

Abstract

A project is described in which the Danish Building Research Institute studied the performance of additional insulation applied to the external solid brick walls of old blocks of flats. In one old block the insulation was placed on the interior of walls: in two other blocks different forms of exterior insulation were tested. Both approaches halved the measured energy consumptions but the exterior insulation was found to be technically better, though consequential architectural treatment was entailed and the pay-back time was longer. In all cases, however, more development is thought to be needed in order to improve the economics.