Fencalc XA2021
SANS 10400-XA:2021 ENERGY EFFICIENCY COMPLIANCE REPORT
Submission to Local Municipality
1. PROJECT INFORMATION
- Project Description: Proposed New Single-Storey Dwelling
- Occupancy Classification: H4 (Dwelling house)
- Building Dimensions: 10m x 15m
- Nett Floor Area: 150 m²
- Location / City: Johannesburg
- Energy Zone: Zone 1 (Medium heating and medium cooling energy)
- Compliance Path Selected: Deemed-to-Satisfy (SANS 10400-XA Section 4.4)
2. GENERAL BUILDING ENVELOPE (Deemed-to-Satisfy)
2.1 Floors (SANS 10400-XA Clause 5.4)
- Construction: Concrete Floor Slab on ground.
- Underfloor Heating: None installed.
- Insulation Required: No edge insulation required (as per Zone 1 without underfloor heating).
2.2 External Walls (SANS 10400-XA Clause 5.5 / Table 2)
- Construction density: >270 kg/m² (Masonry)
- Wall Type: 270mm Masonry cavity wall, plastered internally (2x 110mm brick with 50mm cavity filled with EPS).
Wall R-Value Calculation Table:
| Component | Thickness (mm) | Thermal Conductivity, k (W/m.K) | R-Value (m².K/W) |
|---|---|---|---|
| Outside Air Film | - | - | 0.040 |
| External Plaster | 15 | 0.800 | 0.019 |
| Outer Masonry Leaf | 110 | 0.770 | 0.143 |
| Cavity Insulation (EPS) | 50 | 0.035 | 1.429 |
| Inner Masonry Leaf | 110 | 0.770 | 0.143 |
| Internal Plaster | 15 | 0.800 | 0.019 |
| Inside Air Film | - | - | 0.130 |
| Total Wall R-Value | 300 | 1.923 |
- Required R-value: 0.60 m².K/W (Zone 1)
- Achieved Total R-value: 1.92 m².K/W
- Compliance: PASS.
Typical Masonry Cavity Wall Section Detail:
2.3 Roof Assembly (SANS 10400-XA Clause 5.6)
- Roof Type: Tiled roof on conventional timber trusses, plasterboard ceiling.
- Required R-value: 3.7 m².K/W (Zone 1)
- Insulation proposed: 135mm Glass wool blanket / bulk insulation (R-Value: 3.37) + reflective foil + specified air gap.
- Compliance: Pass (Total assembly R-value ≥ 3.7).
3. FENESTRATION CALCULATION (SANS 10400-XA Clause 5.3)
- Fenestration Definition: Windows and glazed doors forming part of the building envelope.
3.1 Window Area Schedule & Sector Calculation
Schedule of Fenestration Elements:
| Window Mark | Width (m) | Height (m) | Area (m²) | Orientation / Sector | Shading Factor |
|---|---|---|---|---|---|
| W1 (Living) | 2.50 | 2.10 | 5.25 | North | Unshaded |
| W2 (Living) | 2.50 | 2.10 | 5.25 | North | Unshaded |
| W3 (Bed 1) | 2.00 | 1.50 | 3.00 | North | Unshaded |
| W4 (Bed 2) | 1.80 | 1.50 | 2.70 | East | Unshaded |
| W5 (Bed 3) | 1.80 | 1.50 | 2.70 | East | Unshaded |
| W6 (Lounge) | 3.00 | 2.10 | 6.30 | West | Unshaded |
| W7 (Kitchen) | 1.80 | 1.20 | 2.16 | South | Unshaded |
| W8 (Bath 1) | 0.90 | 0.90 | 0.81 | South | Unshaded |
| W9 (Bath 2) | 0.90 | 0.90 | 0.81 | South | Unshaded |
| D1 (Front Door) | 1.80 | 2.10 | 3.78 | North | Unshaded |
| D2 (Back Door) | 0.90 | 2.10 | 1.89 | South | Unshaded |
| Total | 34.65 |
- Nett Floor Area: 150 m²
- Total Fenestration Area: 34.65 m²
- Fenestration Percentage: 23.1% (34.65 / 150 * 100)
Note: Since total fenestration exceeds 20%, compliance must be demonstrated using SANS 10400-XA Table 4 ("Area weighted average maximum whole fenestration element performance values").
3.2 Performance Requirements (As per Table 4 for ≤ 25% Fenestration)
Based on the Deemed-to-Satisfy tables for a fenestration area up to 25%, the following maximums apply:
| Parameter | Sector | Required Maximum | Proposed Material Specification | Achieved Specs | Compliance |
|---|---|---|---|---|---|
| Total Whole Window U-Value | All | 5.20 W/m²K | Low-E Single Glazed in Aluminum Frame | 4.80 W/m²K | PASS |
| SHGC (Without Shading) | North, East, West | 0.49 | Clear Low-E Solar Control Glass in Aluminum Frame | 0.45 | PASS |
| SHGC | South | Any solution | Standard Clear Glass in Aluminum Frame | 0.81 | PASS |
Note: Specific manufacturer (ANSI/NFRC compliant) certificates for the chosen glazing and frame combinations must be provided by the glazier prior to installation.
4. SERVICES & ENERGY REQUIREMENTS (SANS 10400-XA Clause 6)
4.1 Water Heating (Clause 6.1)
- Occupancy Profile & Demand Calculation:
- Occupancy Class: H4 (Dwelling House - Category 1)
- Average Daily Usage: 64 Litres per person per day (at 60°C).
- Assumed Occupancy: 4 Persons.
- Total Daily Demand: 256 Litres/day.
- Requirement: At least 50% (volume fraction) of the average annual hot water heating requirement shall be provided by means other than electrical resistance heating.
- Storage Requirement:
- Standard Minimum Storage (H4 Class): 45 Litres/person = 180 Litres total.
- Using Solar Water Heaters: Storage must be 50% larger = 270 Litres minimum.
- Proposed System: 1 x 300L High-Pressure Solar Water Heater (SANS 1307 compliant) with electrical backup.
- Pipe Insulation (Clause 6.1.6 & Table 11):
- Pipes ≤ 80mm diameter: Insulated with an R-value ≥ 1.00 m².K/W.
- Compliance: Pass.
4.2 Lighting (Clause 6.2)
- Requirement (Table 12): The maximum allowable lighting power density for H4 (Dwelling house) occupancies is 4 W/m².
- Calculation:
- Nett Floor Area: 150 m²
- Maximum Allowance: 150 m² × 4 W/m² = 600 Watts.
- Proposed System: The entire dwelling will be fitted with Energy Efficient LEDs (as stipulated in Clause 6.2.2) to ensure the total connected load remains below 600 Watts.
- Compliance: Pass.
4.3 Air Conditioning / Space Heating (Clause 6.3)
- Requirement: Any installed unitary and packaged air-conditioning equipment must meet the Minimum Coefficient of Performance (COP) as per Table 13.
- Proposed System: Should the owner install unitary split units (e.g., <7 kW capacity), they must have:
- Minimum Cooling COP (COPC) = 3.0
- Minimum Heating COP (COPH) = 3.2
- Compliance: Pass (To be certified by HVAC installer upon fitment).
5. DECLARATION BY COMPETENT PERSON
I, ________________________ (Name), being a Competent Person as defined in the National Building Regulations, hereby confirm that the energy efficiency design for the above-mentioned property has been done in accordance with the Deemed-to-Satisfy requirements of SANS 10400-XA:2021 Edition 2.
Registration Number (e.g., SACAP/ECSA): ________________________
Signature: ________________________ Date: ________________________
Disclaimer: This is a sample reference document generated based on the SANS 10400-XA:2021 Guidelines and Standards. Ensure all exact figures align with your specific architectural drawings and final material selections prior to municipal submission.