The Complete Guide to House Extensions

Adding an extension onto your house can take a lot more effort than renovating or converting an existing space like a garage, basement, or loft, but it is the most effective way of adding new, liveable square feet to a property.

Here, we’re going to take a look at everything you need to know about building an extension. From the different kinds of extensions to the different steps of the planning and building process. We will even share a few tips on how to clear all the necessary paperwork and ways to end up with an excellent extension without going over your budget.

house extensionsBuilding an extension - Checklist

First, let’s take a look at the steps you have to go through to end with the extension you want. We will take them in order, so you have a frame of reference to see how much is left to be done and ensure you’re not skipping any vital plans.

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· Step One: Planning

· Make sure there are no legal barriers to getting an extension. The work can’t begin before you’ve gotten approval from your local council. This can be the longest part of the process (and one we cover further down in the article) so you need to start this in advance.

· If you have neighbours, consider talking to them about the extension before time. Resolving any issues with them ahead of time could stop them from causing major delays to the project.

· Select a team of builders as well as some house extension plans. Thoroughly consider your wants and needs while studying plans on the market and make sure you understand them before agreeing to them. If any changes have to be made, you have to resubmit the plans for approval.

· Step Two: Contracts

· Read through the contract documents to make sure you understand them fully. If there’s something you don’t understand, having some legal advice before you sign is a wise idea. Legal advisors can also help you identify whether anything essential is missing.

· Get to know the timescale of the project if it’s a fixed-time contract. Knowing when it’s planned to start and finish can help you plan for it, and it’s important to know what your rights are if it goes beyond the agreed-upon period.

· If you are buying your own materials or installations to be fitted as part of the extension, such as electronic appliances, bring it up with the builders ahead of time. You want to make sure they are covered by insurance in the case of theft or damage during construction.

· Step Three: Building

· Keep a simple and organized filing system for tracking all the paperwork that can build up before and during the construction process. You need to keep track of contracts, plans, receipts, and any other records related to the project.

· Keep your own records of progress, including conversations with builders, project leaders, and any surveyors you need. This way, you can better track progress and understand what is done and what still needs to be done.

· If you’re not present on the site during construction or temporarily living away from the home, try to visit the site as frequently as possible. Similarly, make sure you swap contact details with someone in the builder’s office, so you can keep each other abreast of any urgent news or changes to the plan.

· After the construction is finished, take your time thoroughly inspecting the work. Any defects that you spot, no matter how large of small, should be listed and reported to the project leader. Any fixes should be free of charge and the sooner you get them done, the better.

· Enlist a building surveyor if the building team doesn’t provide their own. They can inspect the building and ensure that it meets the minimum standards of building regulations.


House extension ideas

You may already be aware that you’re in dire need of an extension, if you’re running out of space for the family or you simply want a room that you don’t yet have. However, there are different ways of adding extensions to the home, each with the own pros and cons. Here are some ideas to help you decide on the kind of house extension you end up building.

· Single-storey extensions: One of the most popular and least costly kinds of extensions, this involves building a single storey room onto the side or rear of the home. Well liked for opening up the home to the garden and the relative simplicity of the project.

· Double or multi-storey extensions: These projects can be significantly more expensive than a single-storey extension and tend to face more issues when looking for planning approvals. On different floors, you can choose between adding new rooms or simply maximizing the potential space of different rooms. An important part of this kind of extension is ensuring that it meets the characteristics of the existing home, including materials used and room form.

· Building above: If you can get approval, adding a storey can be the single most effective way of giving your home extra space. You can literally double up on the floor space available on a one-storey home will keeping just as much outdoor space. This is an expensive and extensive option but can be a great choice if you don’t have a lot of room to move out onto a smaller residential block.

· Building underneath: This involves excavating the soil and rocks underneath the property to add more space. Even a small project of this type can be extremely expensive, thanks to the logistics, structural changes, and the need of extra features like damp-proofing. However, it can be a way to get around certain building restrictions.

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Choosing the right type of extension requires you to figure out how much you can budget towards the project, as well as the particular circumstances of your property and the kind of space you want to add. Some options may prove to be naturally more appealing because the others aren’t a practical or viable choice.

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Where to start

Essendon-Extension-400x300If you want to get started, then getting the ball rolling immediately is crucial. Building an extension takes time, and the process of getting approval can be particularly lengthy. The first step is setting a budget. Work out how much you can spend in total and update it as you finalise project plans. Ensure your budget has some money left over for unforeseen costs, too.

Figure out what kind of extension you want and understand the practicalities of the situation. For instance, are you likely to get permission for that single-storey, double-storey, or floor addition extension? Furthermore, you need to figure out whether you are likely to need to spend time living or staying away from the home and how that factors into the budget. Considering how much value an extension may add to the home can help you work out whether or not it’s a worthwhile investment, too.

After that, you need to get a plan and choose a builder. You can enlist an architect (or one may be provided by the builders) to design it or buy pre-made plans, ensuring they meet your needs and fit you budget. When choosing a builder, you want to make sure they are experienced, accredited, have a good reputation, and have experience in building extensions in particular.

Budget saving tips

You should have your budget set out well in advance and make sure that you have enough money for the particular kind of extension you want, as well as a little extra funding for unforeseen costs. That said, there is a lot that you can potentially do to save money before and during the construction process, so here are some budget saving tips to make everything much more affordable.

· If your plans allow for it, keep demolition to a minimum. Any demolition, such as knocking down a wall, can require extra expenses like wall propping, replacing old flooring, and reconfiguring existing electricals.

· Address inclusions and variables with your builders so you have a better idea not just of the initial budget, but a good estimate of what the costs can really rise up to be.

Beaconsfield-Malvern-Extension-400x266· Beware of the knock-on effect. Making certain changes, such as the aforementioned example of removing a wall, can result in all the costs mentioned above. Talk to your builder about what work is needed to facilitate any changes you might want to make so you don’t sign yourself up to a plethora or new costs.

· If you’re adding more plumbing, try to make sure that it’s easy to connect to your existing system. Keep your plumbing stacks in line as existing bathrooms are designed to be very close to the existing plumbing.

· Consider the building efficiency. Choices you make in the design phase can make the building process much more efficient and thus less costly. By minimizing the amount of trades necessary for different parts of the project, you can save on the costs of hiring extra subcontractors. For instance, when choosing flooring, you might opt for concrete instead of wood because you have already hired out the concrete truck and don’t need to hire and wait for a carpenter to complete a concrete floor.

· Consider prefabricated structures like timber building frames that can both be cheaper and allow your builders to save on a lot of the work of building a frame from scratch.

· Keep an eye out for any more savings that you or your building team spots. You never want to compromise quality work for cheapness, but there may be little savings to be made here and there.

Red tape

Building an extension can potentially be a legal minefield. There’s a lot of red tape to navigate and, though your builders, surveyors, and legal advisors should be able to help you through them, mistakes are still made. Pleading ignorance if your project is found to have not been entirely legal won’t save you from a fine, so bear in mind the following requirements:

· The development application: The first step in seeing how much red tape you have to deal with. Submitting a development application includes a host of documents that the planner can provide, including floor plans.

· Planning permission: The planner in the local council will let you know whether planning permission is required and may require extra documents. Planning permission can differ from area to area, including local regulations on extension size/height.

· Building permission: Also known as building approval or a construction certificate. This step requires you to create a building application with the building team, including details on what construction methods are to be used, how long any fixed-period projects are, and whether it complies with building codes and plumbing regulations.

· Owner/builder requirements and permits: If you are planning to be the construction project leader of your own extension, then you also need to get a special permit. This often entails taking on a lot more responsibility and completing an owner/builder education course.

· Meeting building regulations: Before, during, and after the construction, you need to ensure the renovation is meeting a series of building regulations, including plumbing regulations, building codes, and termite treatment requirements. Having a building surveyor can help you ensure that everything is above board.

Where you build can dictate a large part of what regulations you need to follow and what permissions you need. You can get many more details by looking at your local council’s website. Check out their planning and building section or visit their offices to be doubly sure of what you need.


Is an extension right for your home?

An extension can quickly add a brand-new room of living space to the home, upsizing your home while also increasing the overall value of the property. If you want to know more about extending your home or you’re interested in starting a project, get in touch with Smith & Sons at 1300 787 577. We are high-quality, local builders with plenty of experience and expertise in extensions and a passion for transforming homes.

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