1. What we have learned about NZEB in 2017
(With thanks to our students)

2. 1 CPC & EPC will both need to be below 0.2 for NZEB

3. 2 Projected PE factors are needed to safeguard investment

4. 3 Default Y-factors are potential signals of incompetence

5. 4 Upskilling in NZEB will require new delivery methods

6. What is NZEB?

7. NZEB Definition
Definition of NZEB for new build residential adopted by DIT:
30kWh/m2a (maximum) measured in DEAP
Including up to 35kWh/m2a on-site renewables
Almost an A1 BER

8. NZEB Definition

9. NZEB Definition

10. NZEB Definition

11. NZEB Definition
Typical BER A3
Typical BER ≈ A1

12. 1 CPC & EPC will both need to be below 0.2 for NZEB

13. Scope of the study 13 Unique New Dwellings studied:
Detached single storey
Detached two storey
Semi-detached two storey
Terraced two storey
Top floor Apartment
Approx. 70% “live” projects
Rural and urban sites

14. EPC target values for NZEB
Average Energy Performance Coefficient (EPC)
Part L = 0.350
NZEB = 0.164
NZEB Range:
0.128 – 0.185
MPEPC

15. CPC target values for NZEB
Average Carbon Performance Coefficient (CPC)
Part L = 0.315
NZEB = 0.157
NZEB Range:
0.134 – 0.189
MPCPC

16. Renewables contribution
Average Onsite Generated Renewables (kWh/m2a)
Part L = 18 kWh/m2a
NZEB = 25 kWh/m2a
(Limit: 35 kWh/m2a)
NZEB Range:
18 – 29 kWh/m2a

17. 2 Projected PE factors are needed to safeguard investment

18. Primary Energy Factor
Primary Energy factor of mains electricity in Ireland 2000 to : : 1.5? 2030: 1.1?

19. Primary Energy Factor

20. Primary Energy Factor
Direct electrical space heating Instant electrical water heating PV renewables Gas boiler
Part L
NZEB
2.19

21. Primary Energy Factor
Part L
NZEB
2.19
1.80

22. Primary Energy Factor
Part L
NZEB
2.19
1.80
1.40

23. Primary Energy Factor
Part L
NZEB
2.19
1.80
1.40
1.00

24. Primary Energy Factor
Part L
NZEB
2.19
1.80
1.40
1.00

25. Primary Energy Factor
Primary Energy Factors will fluctuate wildly as the grid decarbonises Buildings which complied when designed may not comply on completion as a result We need a building lifetime average PE factor to design to Is it unreasonable to suggest it be set at 1.1 for buildings due for demolition after 2075?

26. 3 Default Y-factors are potential signals of incompetence

27. Y-Factor Calculated to default spread 0.01 to 0.15 50% of heat losses

28. Y-Factor
Detail selection Psi-value spread to 0.181

29. 4 Upskilling in NZEB will require new delivery methods

30. 5 Upskilling in NZEB will require new delivery methods

31. A word of advice to suppliers …

32. Glazing Type
Part L 25% triple glazed
NZEB 89% triple glazed

33. Main Fuel Type
Part L 9% electrical
NZEB 75% electrical

34. And now its over to our upskilled graduates …