‘Re-coding’ environmental regulation – a new simplified metric for daylighting verification during the window and indoor space design process

ABSTRACT

The role of regulation in fostering or hindering sustainable development has been largely discussed. Yet, empirical studies on how to act in reviewing and modifying normative structures seem to be lacking within the academic debate. This work presents the experience undertaken by the research center FULL at the Politecnico di Torino (Turin, Italy), in supporting the local Municipality to simplify, disambiguate and redefine the current environment/energy regulation system. The paper particularly focuses on the methodological approach utilized to review rules in relation to daylighting in the local Energy Annex Code. This document contained mandatory and voluntary requirements and includes daylighting among the voluntary ones, through the average Daylight Factor DF_m. It also addressed the window design through the RAI (Ratio Aerial Illuminating, defined as window area to room area ratio). The Municipality reports that building practitioners underuse the daylighting practice based on DF_m, rather relying on RAI, because of its simplicity. Consequently, the Municipality gave mandate to FULL to define a new daylight indicator, to be included among mandatory requirement and meant to be more accurate than RAI but simple enough to promote its application. For this purpose, the ‘RAI-enhanced’ indicator was defined, as a function of: (i) glazing area S_g; (ii) glazing visible transmittance T_v, (iii) floor area S_floor; (iv) obstruction angle α, considering buildings ahead of window, overhangs, and loggias. Based on the results, the paper explains how the daylighting part of the energy regulation system was informed and reviewed in the case of the Municipality of Turin.

KEYWORDS:

• Re-coding
• daylighting regulation
• RAI-enhanced
• daylight common practice
• Energy Annex Code

Acknowledgements

The authors wish to express their most sincere gratitude to the researchers of FULL, particularly to Lucia Baima, Caterina Barioglio, Daniele Campobenedetto, and Giulia Sammartano. The authors are also extremely grateful to Professor Franco Pellerey of Politecnico di Torino, for his valuable support in mathematical modeling.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 The Re-Coding is a project headed by Professors Matteo Robiglio and Francesca Frassoldati. The research is carried out by Lucia Baima, Caterina Barioglio, Daniele Campobenedetto and Marianna Nigra.

2 This data were the output of the analysis and observations undertaken by the Municipality of Turin on the number of project approvals requested in the last years since the implementation of the Energy Code Annex. The data were shared with the center FULL during several meetings, workshops and seminars run from May 2019 to February 2020.