• Reduce emissions by 27% (non-domestic on average)
• CO2 target (TER) plus new primary energy target (TPER)
• Notional building U values tightened
• New emission factors including for electricity monthly values
• New emission factors for heat networks
• New Part O (overheating) for residential elements
• Solar gain checks for non-residential spaces
• 1000m2 non-residential buildings need to produce a TM54 energy forecast
• CIBSE 2016 TRY weather files are to be used in place of 2006

• Weather files upgraded to DSY1 for Part O overheating simulation

• Side & top-lit space types now affect notional fabric
• High & low hot water demand classification added
• Notional building heating fuel as actual
• Notional building U values tightened
• Notional non-repeating thermal bridging allowance is 10% (actual is 25%)
• Notional building now includes PVs (unless heat pump)
• Revised approach for determining the illuminance level for a zone in the Notional building
• Revised approach for accounting for primary energy due to electricity generated on-site by renewables
• Updated options for HVAC systems (added added ‘VRF’ and ‘Chilled ceilings or passive chilled beams and mixing ventilation’ )
• Calculation of the corresponding fan energy
• Revised approach for calculating the fan energy associated with demand control of ventilation
• Emission factors for electricity values are now monthly
• New grid displaced PV energy source added
• New district heating values (still as single input value for CO2 Factor & Primary Energy factor)
• In the AB you specify new/existing  district heating this influences NB factors directly

• Size, shape, zoning, topographical shading & weather is the same as the actual building as 2013
• Local shades are ignored
• Openings  are generated with the same dimensions as 2013
• Non-repeating thermal bridging allowance is 10% (actual is 25%)
• Air permeability tightened to 3 & 5 m3/h.m2 at 50Pa (side/unlit & top-lit)
• Aux energy: pump power density is the same as 2013
• Aux energy: fan pump power density is the same as 2013 except for HEPA filters (Hosp_OpTheatre)
• Aux energy: local mechanical exhaust is the same as 2013
• Power factor is the same as 2013
• PVs included based on equation 9 but reduced if heating demand is met with a heat pump (100% demand met means no PV in NB)
• Lighting design illuminance: set as the Actual building but clamped to the maximum or minimum illuminance as per activity (template)
• The general lighting  is based on lighting with efficacy of 95 luminaire lumens per circuit-watt; so a notable tightening over 2013 value of 60
• Display lighting LPD:  luminous efficacy of 95 light source lumens per circuit-watt so the display lighting power density in the Notional zone will be from the NCM Activity Database multiplied by 0.158 (2013 was 0.682)
• Parasitic power density to 0.1 W/m2 for photoelectric or occupancy dimming control (2013 was 0.3)
• U values overall tighter for side & unlit activities; windows at 1.4, although top-lit roof-lights are more generous at 2.1
• Thermal capacity is light / very lightweight
• Construction details (app A): layers have been updated
• Heating fuel & efficiency set by the actual building
• High & low hot water demand classification &  actual fuel sets notional seasonal efficiency, fuel & if-storage for notional building DHW
• Cooling SSEER is revised and heat recovery efficiency is revised

• Non repeating thermal bridging allowance + 25% (notional & reference 10%)
• Pump power densities the same as 2013 but new entries for VRF / chilled ceilings
• Fan power density equation 15 has changed (now x 0.85)
• Lighting design illuminance must be pro rated to NCM minm. in activity database when less than the NCM minm.
• Lighting inference:  luminaire luminous efficacy value of 95 (2013 uses 60)
• Demand control ventilation aux energy adjustment has been revised
• Modular & potable buildings TER & TPER factors revised
• Criterion 3 limiting solar gains: benchmark glazing g-values and for type 3 area have been reduced (type 1&2 where 0.68 in 2013)

• Definition is the same as 2013
• Construction U values & thermal mass are the same as 2013
• Non-repeating thermal bridges allowance 10% same as 2013
• HVAC now defines all spaces as naturally ventilated with the same 27degC cooling setpoint as 2013
• The HWS seasonal efficiency is the same as 2013
• Lighting illuminance level is defined similar to that for the notional building; the W/m2. 100 lux values are the same as 2013
• Manual switching is defined the same as 2013