What drives the cost of building a house in Cape Town

“What does it cost per square metre?” is usually the first question we are asked. It is a fair question, but the honest answer is that it depends, and the range is wide. Two 300 m² houses on the same street can differ in cost by a factor of two. Here is what makes the difference.

The site

Slope. A flat plot is the cheapest to build on. Cape Town has a lot of steep sites, especially on the slopes of the mountain and along the Atlantic seaboard. Steep sites need retaining walls, more excavation, deeper foundations and often more structural engineering.
Ground conditions. Rock has to be broken out. Soft sand or clay may need special foundations. A geotechnical investigation is a small cost that avoids big surprises.
Access. If a truck cannot get onto the site, everything is carried by hand or craned in. Narrow streets, steep driveways and parking restrictions all add time.
Location. Sites close to the sea need materials that survive salt air, which costs more (see building near the sea).

The design

Shape. A simple rectangle with a simple roof is the cheapest form to build. Every corner, step and change in roof level adds labour and materials.
Structure. Large open spans, cantilevers, suspended slabs and big glazed openings need steel and concrete. They make beautiful houses, but they cost more.
Number of storeys. Going up saves land but adds a staircase, a slab and more scaffolding.
Wet areas. Bathrooms and kitchens are the most expensive rooms per square metre. A house with five bathrooms costs a lot more than one with three, even if the floor area is the same.

The finishes

Finishes are where budgets are made or broken. The structure of a house might be similar from one project to the next, but the difference between standard and high-end finishes can be bigger than the cost of the shell. The main items are:

Windows and doors (steel and thermally broken aluminium cost much more than standard aluminium)
Kitchen and joinery
Flooring and tiling
Sanitaryware and taps
Lighting, automation and electrical points
External works: paving, pools, walls and landscaping

Many cost surprises come from “provisional sums” in a quote: allowances for items that have not been chosen yet. If your tiling allowance is low and you pick a tile that costs three times as much, the price goes up. Choosing finishes early is the best way to get an accurate price.

Professional and statutory costs

On top of the building cost, budget for the architect, engineer, quantity surveyor if you appoint one, plan submission fees, NHBRC enrolment for a new home, and connection fees for services. These can add a meaningful percentage to the total.

Where you can save

Keep the form simple and spend on the things you touch and see every day.
Make decisions early. Changes after work has started are the most expensive kind.
Avoid over-specifying hidden items, but never cut corners on waterproofing, structure or drainage.
Phase the work. Landscaping, a pool or an outbuilding can sometimes wait a year.

Getting a realistic number

The most reliable way to know what your house will cost is to have a properly priced bill of quantities or a detailed quote based on drawings and a specification. A figure per square metre is useful for a first conversation, but no more than that. If you have plans, even early ones, send them to us and we will give you an honest idea of the cost.