The cost of house extensions in

As a general rule, an 80 square metre ground floor house extension costs R1,600,000 – R3,200,000, or approximately R20000/m2 to R40000/m2. The difference is in the type of construction and the quality of the inclusions. A second storey home extension costs about 50 percent more than a ground floor extension.

When you buy a home, you may not take a growing family into consideration. One day, you might face a dilemma – should we move to a larger home or add on house extensions?

Moving can be expensive and time-consuming, while adding house extensions can add value to your home and allow you to stay in your current location. But how much does an extension cost? Read this page to find out:

  • Why consider house extensions?
  • How much does an extension cost?
  • Other house extension costs to consider
  • How to save on home extension costs
  • Getting quotes for home extensions
  • Are house extensions worth it?

Why consider house extensions?

Why consider a house extension when you could sell your house and move to a larger home? Here are four good reasons to consider adding house extensions:

1. If you like the area you’re living in, you don’t have to move

2. Make the changes you want to make, don’t settle for something that’s just ‘okay’

3. A home extension may be more affordable than moving to a larger home

4. You may be attached to your current home and not want to leave

Remember that moving involves expenses and a great deal of effort. First, you have to put your home on the market and look for a suitable new home. If your house is smaller than you would like, a larger home is going to cost more. Think about moving costs, bank charges and other costs, and the cost of extending a house may be less expensive than moving.

How much does an extension cost?

You won’t know the exact cost of extending a house until you’ve made plans and know how large the extension is going to be and what will be included. As a general rule, an 80 square metre ground floor extension costs between R1,660,000 and R3,220,000, which works out to approximately R20000/m2 to R40000/m2. The difference is in the type of construction and the quality of the inclusions.

If you’re adding a second storey, house extension costs will be about 50 percent more than a ground floor extension. The reason for this is because a second storey doesn’t require foundation work and other major expenses. If you want to add a second storey, the average square metre cost is between R30000 and R35000. This will be cheaper than making a larger ground floor extension and less land will be needed for the extension.

These are the basic home extension costs, but depending on what needs to be done, it could be more expensive. For example, you may need to have excavation work done. That will add to the cost. Since home extensions involve knocking out a wall, that may be an extra expense and the home may also need some minor renovations.

Options such as prefabricated home extensions are cheaper, but you’ll be limited in your choice of designs and materials, so might not get to realise your personal home extension ideas.

Other house extension costs to consider

Basic home extension costs normally account for roofing, cladding, interior cladding, insulation, windows and doors, but there can be other expenses to consider, such as:

  • Heating and air conditioning
  • A bathroom or kitchen will involve extra costs
  • Quality materials and fittings will cost more
  • The cost of having plans drawn up and municipality fees
  • Furnishing the extension when complete

Home extensions are essentially waterproof shells. They won’t be ready to move in when finished, as they won’t include furnishings, blinds or curtains, lighting fixtures or other items. If a bathroom or kitchen is needed, the cost of plumbing and bathroom or kitchen fit outs has to be factored into the cost. How much will a bathroom or kitchen cost?

A typical bathroom renovation costs:

  • R25,500 to R150,000 for a budget bathroom
  • R150,000 to R250,000 for an average sized bathroom with mid-range fittings
  • R250,000+ for a high-end bathroom

Bathroom renovations include ripping out the old bathroom. If you’re adding a home extension, bathroom builders won’t have to tear out old fittings, but you will face other expenses. For example, the plumber will have to install pipes and sewerage. An electrician will have to install new wiring, lighting and outlets. Because of these expenses, a new bathroom may cost closer to the higher end of the scale.

A typical kitchen renovation costs:

  • R100,000 to R220,000 for a budget renovation
  • R220,000 to R350,000 for a mid-range kitchen
  • R350,000+ for a high-end kitchen

Like the bathroom, the cost won’t include tearing out an old kitchen, but will include new plumbing and electricity. You won’t know how much a new kitchen will cost until you get quotes from kitchen installers, plumbers and electricians, but the cost will probably be higher than a kitchen renovation.

A bathroom or kitchen tends to involve greater expense than most other home extensions. If you feel your current kitchen is too small, what else would you use the space for? Think about ways to make it feel more spacious. Add larger windows or, if you don’t have an open plan kitchen, you could knock out a wall to make the kitchen feel larger.

You may need a bathroom in a house extension, but how large does it need to be? If you already have a larger bathroom, an ensuite bathroom may be all you need. It will cost less than a large bathroom and may be perfect for the extension.

How to save on home extension costs

Keep in mind that a house extension costs more than just the cost of building. If you want to avoid going over-budget, you need to consider all the costs before you commit to an extension. Do all your costings first and don’t leave anything out, remembering to account for:

  • Furnishings
  • Lighting
  • Curtains or blinds
  • Heating and air conditioning
  • Flooring
  • Painting
  • Exterior painting if needed
  • Excavation work

The size of home extensions is one of the biggest factors affecting cost. Consider whether you really need 80m2 or if a smaller extension could be more within your budget. A 60m2 extension can save between R200,000 and R750,000, depending on the quality of inclusions, and that amount of money can pay for most if not all of the furnishings, curtains and other inclusions.

A cost-effective alternative to building home extensions is to convert a garage into a room. Bringing a garage up to the standard required for living space isn’t cheap, but with overall costs averaging R75,500 to R200,000, you’ll save money compared to the usual home extension costs.

If you have a smaller property, a garage conversion also means you won’t have to lose any outdoor space. However, you may not be able to convert a garage unless you also have a second garage or carport, depending on the rules where you live.

Getting quotes for home extensions

When you apply for quotes from local builders, check the quotes you receive carefully. Do they include knocking out walls or excavation work? If not, those will be additional expenses. Some home extension builders will include everything in their quotes. If a quote is higher than another, it may include these extra costs.

If in doubt, ask builders what’s included in their quotes and what’s left out. A quote should list everything. If it doesn’t, a builder may be trying to get your business by undercutting other builders. They will add these other costs on later though, so make sure you know what’s included from the start.

Are house extensions worth it?

A house extension isn’t cheap, but moving to a larger house can be even more expensive. The house will cost more and you will have other expenses to think about. These will likely include:

  • Real estate agent’s commission
  • Marketing the home
  • Conveyancing
  • Cleaning and/or styling your home
  • Possible repairs or renovations
  • Moving costs

Add up all the costs and a house extension is usually less expensive than moving. It can also be easier, since you don’t have to leave the home while building is going on and you can go about your daily business. As a bonus, if you decide to sell, the house extension can add its value or more to the cost of the home. Home extensions make good sense, both economically and for your peace of mind.

To see more ‘price of’ guides visit the ‘Cost of homes services‘ page to see a full list.


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