South African homeowners looking to expand their living space are facing significant costs, with prices for extensions ranging from R80,000 for small glass structures to over R1.2 million for large brick builds.
House extension costs in 2025 vary widely, with current prices averaging between R7,000 and R15,000 per square metre. High-end or complex projects with premium finishes can reach up to R20,000 per square metre.
According to Lew Geffen Sotheby’s International Realty, extensions remain one of the most in-demand property upgrades, driven by families needing more space and the continued trend of remote work.
A modern sunroom or conservatory is the most affordable option, starting at around R80,000 for a small aluminium and glass build.
Mid-range systems typically cost between R150,000 and R350,000, while larger or premium options featuring laminated glass, automated louvres or tiled roofing can reach R800,000.
Sunrooms can usually be installed within three to eight weeks once municipal approval is obtained, as most are prefabricated and assembled on-site.
A brick-and-mortar extension is considerably more expensive and time-consuming. A modest 4m x 4m single-storey build starts at roughly R250,000, with standard extensions generally costing between R400,000 and R800,000.
Larger or high-end projects, particularly those with complex structural work or luxury finishes, can exceed R1.2 million.
Unlike prefabricated sunrooms, brick builds typically require at least three months to complete, depending on local authority approvals, labour availability and site conditions. Homeowners should also expect greater disruption during construction.
Property analysts note that conservatories and sunrooms, while relatively uncommon in South Africa, are becoming increasingly popular among buyers for their cost efficiency and fast turnaround times. Brick extensions, however, remain the preferred choice for fully integrated spaces such as additional bedrooms, kitchens or home offices.
Building industry experts caution that final costs can vary significantly based on materials, glazing quality, labour rates and current construction demand.
According to the 2024 Turner & Townsend survey, average construction costs in Johannesburg now sit at R17,791/m², while Cape Town leads with R19,589/m².
| Extension Type | Price Range (per m²) |
|---|---|
| Standard | R7,000 – R10,000 |
| Mid-range | R10,000 – R15,000 |
| Luxury | R15,000 – R20,000 |
The cost breakdown also goes beyond bricks and mortar. High-end kitchens can cost over R150,000, bathroom installations may reach R25,000, and professional fees—from architects to engineers—can account for 10–15% of the total build cost. Budgeting for the unexpected is essential.
Ooba noted that professionals who will need to be involved in the construction of the home include the quantity surveyor, architect, various engineers (an engineer must always be on-site during the construction) and geologists.
Here are estimated fees you should set aside for the various professionals involved in construction:
Architect: up to 8% of the construction cost.
Land surveyor: up to 5% of the construction cost.
Structural engineer: 2% of the construction cost.
Quantity surveyor: up to 4% of the construction cost.
Extending a home remains a major financial investment, but with South Africans spending more time at home, demand for additional space is expected to remain strong through 2025.












