1. Energy Efficiency Standards
June2012
LK Reynolds
Sustainability Development Executive

2. Government gazette – 9 September 2011
Implementation – 9 November 2011
Applicable to new plans & renovations needing plan approval

4. CONTENT OF THE PRESENTATION
Introduction
NBR-XA
SAN XA
Additional Requirements
SANS 204
Green Buildings
FAQ’s
Conclusion

5. INTRODUCTION Energy efficiency (EE) in buildings is www (win win win)
South Africa’s energy demand – Demand > Supply
Load shedding
Huge price increases
Buildings are the largest end use of energy and account for 40% of end use of energy & 23% GHG.
Most of this consumption is for heating, cooling, ventilation and hot water
South Africa signatory to Kyoto protocol
Generally not designed or constructed to maximize energy efficiency
Feasible saving potentials for EE are very large both in new and existing buildings

6. National Building Regulations
Under previous Standards Act – SABS was mandated to administer National Building Regulations and Building Standards Act.
NRCS Act of 2008 promulgated
National Building Regulations responsibilities transferred to National Regulator for Compulsory Specifications (NRCS)
Both SABS & NRCS report to DTi
Enforcement of NBR is responsibility of Local Government
NRCS also mandated to ensure proper implementation & execution of NBR

7. Aim Of NBR To ensure safe buildings based on
Acceptable building science practice
Good workmanship
Quality materials
Not intended to be handbook on good building practice
Simple & short way to ensure that buildings will be designed & built so that persons may live & work in a healthy, safe environment
Other aspects affecting comfort & convenience are not controlled by NBR

8. National Building Regulations and Building Standards Act, 1977
(Act 103 of 1977)
National Building Regulations
(Functional Regulation)
Agrėment
Deemed-to-Satisfy
SANS 10400
The Application of the National Building Regulation
Rational Design 8

9. Regulatory Framework
National Building Regulations and Building Standards Act, 1977 (Act 103 of 1977).
National building regulations are issued in terms of the above act and is a compilation of various parts (A to X:–
Part A – General Principles and Requirements
Part B – Structural Design :
Part X – Environmental Sustainability
Part XA – Energy Usage in Buildings
SANS is a National Standard:
The Application of the National Building Regulations (also compiled in many parts to correlate to the National Building Regulations)

10. National Building Regulation XA

11. Rationale behind NBR-XA structure
Biggest energy user in residential buildings – Hot water supply.
Look to renewable energy or energy efficient sources
XA2
Biggest energy driver is comfort
Heating, cooling & ventilation
Building envelope & services
XA1

12. Part XA – Energy Usage in New Buildings
XA1 - In order to contribute to the reduction of greenhouse gases, buildings and extensions to buildings in respect of which plans and specifications are to be drawn and submitted in terms of the Act, having A1, A2, A3, A4, C1, C2, E1, E2, E3, E4, F1, F2, F3, G1, H1, H2, H3, H4 and H5 occupancies or building classifications in accordance with Regulation A20, excluding garage and storages areas contained within such occupancies, shall be designed and constructed so that they:
a) are capable of using energy efficiently while fulfilling user needs in relation to vertical transport, if any, thermal comfort, lighting and hot water; or
have a building envelope and services which facilitate the efficient use of energy appropriate to its function and use, internal environment and geographical location.
Equipment and plant required for conducting the business of the occupant shall be excluded from these requirements.
XA2 - At least 50 % by volume of the annual average hot water heating requirement shall be provided by means other than electrical resistance heating including but not limited to solar heating, heat pumps, heat recovery from other systems or processes and renewable combustible fuel.
XA3 - The requirements of sub-regulation XA1 shall be deemed to be satisfied when such building is designed and constructed in accordance with the following requirements:
a) has an orientation of the longest axis, shading, services and building envelope in accordance with SANS XA; or
b) is the subject of a rational design by a competent person, which demonstrates that the energy usage of such building is equivalent to or better than that which would have been achieved by compliance with the requirements of SANS XA; or
c) has a theoretical energy usage performance determined using certified thermal calculation software, less than or equal to that of a reference building in accordance with SANS XA.

13. Occupancies included Class of Occupancy Type of Occupancy A1
Entertainment and public assembly A2
Theatrical and indoor sport A3
Place of instruction A4
Worship C1
Exhibition Hall C2
Museum E1
Place of detention E2
Hospital E3
Other institutional (residential) E4
Medical facilities F1
Large shop F2
Small shop F3
Wholesaler’s store G1
Office H1
Hotel H2
Dormitory H3
Domestic residence H4
Detached dwelling house H5
Hospitality

14. Occupancies excluded A5 - Outdoor Sport
B1,B2,B3 - Commercial Service Building
D1,D2,D3,D4 - Industrial and Plant rooms
J1,J2,J3,J4 - All garages and storage areas are excluded.

15. NBR-XA If mixed occupancy – applies to relevant segment
Where provided, max 50% by volume of hot water can be from a traditional geyser (paraphrase)
Buildings shall be designed and constructed so that they
a) are capable of using energy efficiently while fulfilling user needs in relation to vertical transport, if any, thermal comfort, lighting and hot water; or
b) have a building envelope and services which facilitate the efficient use of energy appropriate to its function and use, internal environment and geographical location.
Equipment and plant required for conducting the business of the occupant is excluded.

16. Hot Water Supply – XA2
Regulation: A minimum volume fraction of 50% of the annual average heating requirement for hot water shall be provided by means other than electric resistance heating or fossil fuels including, but not limited to
Solar heating
Heat pumps
Geothermal heat
Renewable combustible fuel
Heat recovery from alternative systems and processes

17. SANS 10400 XA Geyser systems and Pipe Insulation - requirements
All exposed hot water service pipes shall be clad with insulation with a minimum R-value in accordance with the table below.
Internal diameter of pipe
Minimum R-value
<80mm
1.0
>80mm
1.5
Determined with a hot surface temperature of 60 °C and an ambient temperature of 15 °C.

18. Compliance to NBR-XA – XA3
1 Rational design
This alternative requires input of a professional “competent” person
Thermal performance of building needs to be calculated
Performance should be equal or better than specified in SANS 10400XA
2 “Deemed-to-Satisfy”
Compliance with requirements in SANS XA
3 Comparison with a compliant theoretical (reference) building
Energy usage of building shall be less than or equal to that of a reference building
Reference building should be designed to “Deemed to Satisfy” standards

19. SANS XA

20. Compliance to SANS 10400-XA: Deemed-to -satisfy
Option 1: Compliance to SANS 10400XA
“Recipe” for building elements
Requirements partially aligned with SANS 204
Option 2: Compliance to Tables
Thermal performance of building needs to be calculated
Max Energy Consumption & Max Energy Demand must comply with tables in SANS XA
Thermal performance calculations software accredited by Agrement SA to be used
This alternative requires input of a professional “competent” person
Option 3: Comparison with a compliant theoretical (reference) building
Building design performance – theoretical max energy consumption & demand shall be less than or equal to that of a reference building
Building should be designed to “Deemed to Satisfy” standards

21. SANS 10400 – XA (Option 2) Energy Usage and Building Envelope
Conceptually based on two principles:
Maximum energy demand per unit area(kVA/m2)
Maximum annual energy consumption per unit area (kWh/m2.a)
Dependent on building classification and climatic region

22. SANS 10400 – XA Energy Usage and Building Envelope
Climatic Zones

23. Maximum Energy Demand 1 2 3 4 5 6 7 8
Classification of occupancy of building
Description of building
Maximum energy demanda
VA/m2
Climatic zone A1
Entertainment and public assembly 85 80 90 A2
Theatrical and indoor sport A3
Places of instruction 75 A4
Worship F1
Large shop 95 G1
Offices H1
Hotel
a The maximum demand shall be based on the sum of 12 consecutive monthly maximum demand values per area divided by 12/m2 which refers to the nett floor area.
b The climatic zones are given in annex B.

24. Maximum Annual Consumption1 2 3 4 5 6 7 8
Classification of occupancy of building
Description of building
Maximum energy consumption
kWh/(m2·a)
Climatic zonea A1
Entertainment and public assembly
420
400
440
390 A2
Theatrical and indoor sport A3
Places of instruction A4
Worship
120
115
125
110 F1
Large shop
240
245
260
255 G1
Offices
200
190
210
185 H1
Hotel
650
600
585
620
630
NOTE 1   The annual consumption per square metre shall be based on the sum of the monthly consumption of 12 consecutive months.
NOTE 2   Non-electrical consumption, such as fossil fuels, shall be accounted for on a non-renewable primary energy thermal equivalence basis by converting mega joules to kilowatt hours.
a The climatic zones are given in annex B.

25. Building Envelope – Option 1
≈ 25% Roof
Summer
≈ 15% Air renewal
Principle of insulation
≈ 30%
Walls
Glazing
≈ 10%
Thermal bridges
Winter
Floor
≈ 10%
≈ 10% Ground
Improving the building envelope can reduce energy losses and shrink energy consumption by up to 90% 25

26. Building Code References
Orientation SANS XA
Shading SANS 204
Walls SANS XA
Fenestration SANS XA + SANS 204
Roof Assembly SANS XA
Flooring SANS XA
Services (excluding hot water) SANS 204

27. Energy Usage & Building Envelope (Option 3) - Orientation - Shading
Compact in plan with most glazing on northern side
Living spaces on northern side
Longer axis of dwelling to be east-west
Roof overhang to shield northern windows in midday summer sun
Shading
As per SANS 204
Projection of roof overhang - ratios

28. Total Energy = Energy for cooling + Energy for heating Total min = optimal orientation  28

29. Total Energy = Energy for cooling + Energy for heating Total min = optimal orientation  29

30. Shading  
Requires a permanent feature which extends horizontally on both sides of the glazing for the same projection distance, P (see next slide for figure on shading feature)
or provides the equivalent shading with a reveal or other shading element (see figure on shading projection) or
have an external shading device which is capable of restricting at least 80% of summer solar radiation.
For glazing where G exceeds 0,5 m, the value of P (see figure on shading feature or device) shall be halved.

31. Shading feature or device
Key
P horizontal distance, expressed in metres, from the glass face to the shadow casting edge of any shading projection
H vertical distance from the base of the glazing element to the same shadow casting edge used to measure P
G vertical distance from the head of the glazing element to the shadow casting edge of any shading projection
NOTE: An adjustable shading device that is capable of completely covering the glazing may be considered to achieve a P/H value of 2.

32. Energy Usage and Building Envelope - Floors
If in-slab or in-screed heating slab to be insulated with minimum R-value of 1
To calculate the R value you need to know (R value = )
The Thermal conductivity (K value) of the product - expanded polystyrene: 0.036
The product thickness: 40mm
R value =
= m²K/W - compliant as a solution
Thickness in meters
K value

33. Energy Usage and Building Envelope - Walls
Non-masonry walls shall achieve a minimum R-value of:
R=2.2 for climatic zones 1&6
R=1.9 for climatic zones 2,3,4&5
Masonry walls shall achieve a minimum R-value of 0.35
Double skin masonry with no cavity, plastered internally; and either plastered externally or unplastered face masonry externally
Single leaf masonry with a nominal thickness of at least 140mm plastered internally and rendered externally

34. Traditional Wall vs. the New Systems
Cavity wall, insulation
R = 1.00
Cavity wall, dry lining
R = 1.69
ETICS on steel frame
R = 3.76
Lightweight steel
frame wall
R = 2.50
ETICS on single brick wall; R = 2.21
R-value required for Zone 1 = 2.20
Quoted R-value is subject to thickness of intervention insulation material 34

35. Energy Usage and Building Envelope –SANS 10400 – XA compliance
Fenestration
Buildings with up to 15% fenestration area to nett floor area per storey are deemed to satisfy
Buildings with fenestration area to nett floor area per storey exceeding 15% shall comply with the requirements for fenestration in SANS 204
Air infiltration shall comply with SANS 613

36. Fenestration Tables – SANS 20436

37. Energy Usage and Building Envelope - Roof Assemblies
A roof assembly shall achieve the minimum total R-value specified in the table hereunder for the direction of heat flow. 1 2 3 4 5 6 7
Description
Climatic zones
Minimum required total R-value (m²∙K/W)
3,7
3,2
2,7
3,5
Direction of heat flow Up
Down and up
Down

38. Calculating the R-value of a roof
The following are taken into consideration when determining the R-value of a roof construction. The figures can be obtained from SANS XA.
1- Outdoor Air film (moving air)
7- Direction of
Heat flow
(Affects figures 1,3 & 6)
2- Roofing Material
3-Roof air space (Ventilated/unventilated)
5-RhinoBoard ceiling
6-Indoor air film (still air)

39. Example - heat flow up
For a building in Climatic Zones 1 & 4 to meet SANS 10400XA requirements, the following figures are used and the R-value of insulation is added.
1- Outdoor Air film (moving air) = 0.03
7- Direction of
Heat flow
2- Roofing Material = 0.02
3-Roof air space = 0.18
(unventilated)
135mm Aerolite Insulation = 3.38
5-RhinoBoard ceiling = 0.06
6-Indoor air film (still air) =0.11
Total R-value =3.77 m²K/W

40. Services Lighting and power
Depending upon occupancy and activity, the minimum lighting levels shall be determined in accordance with the requirements of SANS and SANS O.
Designers are encouraged to use daylighting in their designs to reduce the energy used.
The energy demand (power) and energy consumption for the building shall be determined in accordance with the requirements given in SANS 204.

41. Mechanical ventilation and air conditioning
Air conditioning or mechanical ventilation systems (or both) installed in buildings shall comply with the relevant national legislation.
The air conditioning or mechanical ventilation system (or both) shall be designed to best practice.
Designed that in the event of failure of an air conditioning or mechanical ventilation system (or both), an alternative means of natural ventilation shall be provided.
All chilled water, hot water and refrigeration piping, conditioned air duct work and flexible ducting shall be insulated to limit heat gain or loss (or both) to not more than 5% from source to furthest point of delivery on a system.

42. Additional Requirements

43. Additional Requirements for BCO
Competent Person (where necessary) – submit documentation to local authority as per SANS A
On Plans
Where provided – location, type & capacity of water heating installations
Where provided – details of fenestration and insulation

44. SANS 204?

45. Why 2 Energy Efficiency standards?
Does this cause confusion?
Look at International trends….

46. Europe: Energy Efficiency Targets for New Residential buildings - 2020
DK, FR, DE: evolution of building energy consumption
England/Wales: Code of Sustainable homes
Poland: evolution of U values walls 46

47. How has this been achieved?
Building methodologies have changed in last 50 years
Driven mainly by speed and energy constraints
Regulation now driving changes
FACT’s
Fire
Acoustic
Cost Effective
Thermal
Comfort and Energy Efficiency 47

48. SANS 204 Energy Efficiency in Buildings
Far more comprehensive than the building regulations and SANS – XA
Requirements more stringent (except for roof/ceilings)
In the longer terms regulation to be upgraded and trend toward SANS 204
It is a voluntary standard
Basic minimum for green star rating
Both standards reduce the use of energy from electricity, gas, oil, or other fuels used in buildings.
Both standards exclude energy used in the operation of the building

49. Green Buildings

50. Green Buildings Aspirational Buildings Green Star Rating Tools
Office, Retail, Multi-unit residential, Public Buildings
Water & Energy Bench-marking (in progress)
Building Interiors & Socio-Economic (starting soon)
Rating for the building/project
“Design” or “As Built” rating
SANS 204 is conditional requirement
More than just energy efficient buildings
Water, waste, transport, indoor environment etc.

51. FAQ’s

52. FAQ’s Does this apply to affordable/RDP/Government subsidized houses?
Yes – there are no exclusions on residential buildings
Does this prescribe the installation of Solar Water Heaters?
No – if not technically feasible, look to other energy efficient technologies
Not applicable if no hot water supplied

53. FAQ’s ctd. Does this call for double glazing?
No – unless building is extreme in design.
How do I know what the R-value is?
Material Manufacturers must supply tested thermal performance values with thickness of material required.

54. FAQ’s ctd. Are products green rated?
No – projects get the ratings not components of the project
How do I know how “green” products are?
Look at the requirements in the Green Star Rating tools & ask manufacturers to supply you with the test certificate results that demonstrate compliance.

55. Conclusion

56. Opportunities
NBR-XA only applies to new buildings and additions/renovations
Encourage to design to SANS 204
Energy costs escalating annually
Supply of energy is always at risk
Big opportunities in retrofit and re-insulation
Continue to manufacture “standard” thickness’s
Compliant buildings will increase in value
Attraction of Tenants
Tax Incentives