Model to Improve Classrooms’ Visual Comfort Using Waste-Based Shading and Its Validation in Mediterranean Schools

Abstract

European non-residential buildings constructed before building energy codes consume more energy and resources than new buildings. Existing educational buildings comprise 17% of this outdated stock. These buildings can be retrofitted to create a conducive learning environment that can improve students’ comfort. The refurbishment of facades is a common solution to improve the energy performance of schools when the aim is to improve the daylighting comfort. This study develops a methodology to optimize facade renovation solutions including (1) preparation, (2) simulations of the simplified model using local shading, and (3) modeling a realistic optimized facade design. This study evaluates visual comfort by considering multiple-dimensional metrics such as useful daylight illuminance (UDI), annual sunlight exposure (ASE), illuminance uniformity, and the daylighting factor. The three parameters of the louvres on which this study focuses are the distance from the new facade to the exterior wall, the blade degrees, and slat spacing. The methodology was first applied to improve the facade proposal with reused roof tiles from the project Waste-based Intelligent Solar-control-devices for Envelope Refurbishment (WiSeR). The results illustrate that implementing these solutions efficiently improves the indoor visual comfort in the classroom while avoiding overheating issues. For a constant-gaps surface, a shading distribution with alternated gaps gives better results for the aforementioned light metrics. Specifically, the most suitable values are a 7 cm distance from the new shading system to the existing wall, slat degrees at 0, and louvre spacing at 21 cm.