What Is The Most Expensive Part Of An Extension?

With property prices still at a premium and the cost of moving by no means small change, more of us choose to add a room rather than sell and move. If you are still undecided, you may want to weigh up the pros and cons of staying put and renovating or selling up. 

The big advantage of renovating and adding a home extension is that you get to stay in an area you have grown to love. Practical aspects such as keeping the kids in the same school and having access to local amenities you are familiar with also count for a lot.

You also get to design the extension to suit your lifestyle and needs and add specific features or fittings you really want.

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:

  • If you like the area you’re living in, you don’t have to move
  • Make the changes you want to make, don’t settle for something that’s just ‘okay
  • A home extension may be more affordable than moving to a larger home
  • 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 A House Extension Cost?

According to assessment experts and design architects Archicentre Australia, an extension to an existing building could cost from $1,900 to $3,600 per square metre. 

This ballpark figure assumes ‘good access to your site and no major structural upgrades’, and the wide range can partly be explained by the scale of your project, the materials you choose and the individual builder you hire. 

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In terms of materials, it is important to know that a timber frame extension is cheaper than a brick veneer extension, while double brick is the most expensive option. Check out our range of dual occupancy builder for your dream house.

If you are adding a wet area as part of your extension then you need to add the following to the above building costs:

  • Bathroom/en-suite: $12,000 – $28,000
  • Kitchen: $15,000 – $40,000
  • Laundry: $6,000 – $15,000

If you are adding a second-floor extension to your home – which includes stairs, any structural work to the existing structure and roof – then you need to budget for a lot more, as much as double the quoted costs above. 

However, some also point out that ‘larger works can achieve a more economical price per square metre’, which sounds counterintuitive but is often the case. 

You may also need to budget for a land surveyor, a soil report, and a structural engineer in terms of specific fees for professionals. And in case anything unforeseen happens – like discovering asbestos in your ceiling, it is wise to add a 10 – 20 per cent buffer to your budget.

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 council 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:

  • $2,500 to $15,000 for a budget bathroom
  • $15,000 to $25,000 for an average sized bathroom with mid-range fittings
  • $25,000+ 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. Planning for a new look for your house? Look no further!  Home Builders  is here to help in your dual occupancy builder Melbourne.

A typical kitchen renovation costs:

  • $10,000 to $22,000 for a budget renovation
  • $22,000 to $35,000 for a mid-range kitchen
  • $35,000+ 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.

What Can I Build for my Budget?

If you’re looking for a larger home, it could be more cost-effective for you to add space to an existing property rather than move house or even self build. Before we investigate some recent projects, how much they cost and what they involved, here are some key ways to get the most out of your home improvement venture:

Identify your needs:

Think carefully about your reasons for extending – are you looking to add more general living space, or do you want a room with a specific purpose, such as an extra bedroom? Thoroughly considering what you want from the finished addition will help form the foundations for coming up with a suitable brief and design.

Set a brief:

Once you’ve determined your motivations and how you intend to use the new space, consider how your property will best respond to the addition. Key areas to focus on are establishing the potential ways that you could maximise space and natural light.

Work with skilled designers:

While you may choose to come up with plans yourself and work with a structural engineer and a good builder to fine-tune the details, an architect or experienced designer’s flair will help you get the most out of your home improvement project.

Assess the opportunities:

When you talk it through with your designer, you’ll probably have a vision for how you think your home can be tailored. Keep an open mind and be flexible – it may even work in your favour.

Consider the rest of the house:

A home extension project will add valuable new living space, but the results can be maximised if you go back to basics and consider how you want to live in your home. The most successful schemes tend to include layout changes and renovation work elsewhere in the house, too.

Cost versus value:

It can be easy to get carried away with all the exciting extension possibilities, but take a moment to step back and have a look at how much value it will add to your house. You might have different priorities if this is your forever home, but as a rule, try not to spend more on a property update than its finished value.

Melbourne House Renovation

Investigate local house prices to get an idea of what uplift you can expect, and check out the Office for National Statistics’ handy extension value calculator to get a quick idea of the potential increase in value.

Understand the planning rules:

You may not need to submit a formal planning application thanks to permitted development (PD) rights. But if your house is in a designated zone (such as a conservation area or an area of outstanding natural beauty) or if the property you’re proposing to extend is listed, your PD rights are restricted.

Create a project schedule:

 While it’s inevitable for there to be a few bumps in the road, by and large, a well-organised scheme should come together smoothly, with minimal changes needed as you go along.

Protect your project:

Ensuring you have the right insurance in place for your extension scheme will protect the new works and the original building from anything that could go wrong during the build.

Engage skilled builders:

When you put the scheme out to tender, be sure to provide enough detail to compare quotes like-for-like. Given a basic outline, one contractor may over-specify to cover all margins, while another might quote cheaply, knowing they’ll charge extras – so provide a clear and comprehensive brief. Busy builders may quote higher, but remember they’re busy for a reason.

Efficient management:

Whether doing it yourself or bringing in a professional, it’s important for the project manager to keep a tight rein. It’s their job to make sure things are done to a high standard at the pace you need.

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 $20,000 and $75,000, 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 $7,500 to $20,000, you’ll save money compared to the usual home extension costs.

If you have a smaller property, a garage conversion 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.

Managing or Reducing Your Project Costs

It pays to get professional advice from a good architect.

They can help you realise the main ambitions for your extension whilst helping control your costs. They will work with you to make sure you get the most out of your budget to recommend where your budget is best spent and where costs would be unnecessary or could be minimised.

Make sure you get 3-5 quotes from recommended builders (your architect can help compile a tender list for you) to get a firm idea of the costs before starting work.

Your architect can also help you with your building contract to prevent any nasty surprises down the line. They can also inspect the builder’s work to ensure it’s being carried out in accordance with the agreed design and specifications.

Shop around.

Designers and contractors are often able to access trade discounts. Alternatively, if you are planning on undertaking some of the work yourselves, Building Supplies Online is a really good website offering trade prices to consumers. Definitely worth checking out for things like tiling, floor finishes, bathroom and kitchen fittings.

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. Home Builders has the best range of dual occupancy builder services to help you create your dream house.

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 later, though, so make sure you know what’s included from the start.

What Permissions And Approvals Will You Need For A Home Extension?

If you are undertaking any structural renovations, such as building a home extension, you will need permissions and approvals from your local council before your project can go ahead.

The cost of these varies, depending on the local council, so be sure to research this beforehand and include it in your budget. Permissions, approvals and permits for your home extension may include:

  • Demolition permit
  • Development application (DA)
  • Building permit 
  • Town planning approval

In most cases, your architect and/or builder will take care of this, but you still need to know what is required and what these could cost. With regard to permissions, councils are particularly concerned with projects that:

  • Significantly alter the appearance of a property
  • Impose on the privacy of neighbours
  • Alter a heritage-listed building

Some building works can be undertaken through a simpler approval process called a complying development, which can be issued within 10 days and help speed up the process.

If your project only involves internal works, you are unlikely to require planning approval, but be sure to check this with your local council when you are in the research phase. 

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 home while the building is going on and 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.

Never embark on a building extension project unless you are fully aware of the cost and job involved. Start by setting a budget and getting quotations from different contractors.  

Allow yourself a contingency. This will ensure you cover any unforeseen expenses due to issues or delays with materials.  

You can save money when building an expansion. For example, you can decide to do some of the jobs such as interior decoration and painting. Doing as much as you can on your own is the best way to reduce the price of building an extension.

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