NZEB reconsidered

: optimality step-changes understood through an urban loose-fit development, within a temperate oceanic climate, as though ‘carbon matters’

Abstract

Energy efficiency legislative in Ireland, mandates that all new buildings, and substantive retrofits, comply with the nearly Zero Energy Building (nZEB) standard, as set out within Part L of the Irish building regulations. The metrics of the nZEB standard have been developed under EU cost optimality guidelines, and are calibrated through two predictive software programmes, DEAP for domestic constructions, and NEAP for non-domestic constructions. They represent the only direct methodologies by which regulatory compliance in Ireland can be achieved, despite there being many other proprietary software programmes available for such use. The premise of DEAP and NEAP being the only deemed-to-satisfy regulatory compliance software packages within Ireland for nZEB buildings is neither justifiable nor beneficial. They fail to structure an adequate performance standard necessary to meet our international carbon emission reduction targets and lack the ambition of ‘stretch’ metrics necessary to promote better construction practices and optimise the embodied carbon used.

The literature review indicates that by improving fabric performance specification to a PH standard we create an opportunity for reduced performance gaps, improved IAQ, and a flexibility of loose-fit across a long-term perspective. The research data indicates that an improved fabric performance also allows for a significant surplus of onsite renewable energy which creates a Zero Emission building standard across its operational year, something that an nZEB building cannot achieve other than through a fully decarbonised power grid. The research data also indicates how reducing the embodied carbon of thefabric allows for a significantly beneficial renewable energy strategy for the buildings.

The design intent originality of the case study research is timely as the EU Parliament has ratified a proposed EPBD (2023), focused on mandating a new standard for all new buildings constructed beyond 2030, equivalent to a Zero-Emission Building. Identifying the step-change pathway necessary within the nZEB standard to create an improved operational profile equivalent to a Zero-emission building is therefore important if we are to achieve our 2030 and 2050 mandated targets. All research has an underlying philosophical outlook. The foundational intent of this research is to communicate by ‘force of example’, the optimality step changes necessary to structure a conceptual shift in nZEB performance, as though ‘carbon arithmetic matters'.

Date of Award	Jun 2023
Original language	English
Supervisor	Shane Colclough (Supervisor) & Philip Griffiths (Supervisor)