What To Consider Before Building A House Extension2

What To Consider Before Building A House Extension?

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    Extending one's dwelling can be done for various reasons. For instance, as families expand, they will need more room. Perhaps you're thinking about building a nursery or even a playroom for the kids.

    You may utilise an extra room in your house for work, study, or exercise. Whatever the reason, expansions are generally a good move and also can increase a home's resale price if done properly.

    Regardless of your reasons for considering a home addition, you must keep certain factors in mind. Extending a building is a time-consuming and costly endeavour. There are, therefore, factors to think about before jumping headfirst into this undertaking.

    The thought of building an addition to your house may be both thrilling and terrifying; we've each heard horror tales from those who've gone before us. Still, that's not how things have to be.

    You can take charge of the process, guarantee that your extension will enhance your lifestyle for so many years to come, with just a little bit of planning, the correct advice, and some discipline. To get you off to a good start, we've provided a list of 10 questions to ask yourself.

    Is Planning Permission Required?

    If you want to add on to your house, you might need to apply for a building permit first. This won't always be required.

    For instance, a detached single-story home can have an 8-meter extension added to the back without needing any special permits. An addition does not require permission unless it takes up more than half of the garden. In addition to not needing approval from the local planning department, any addition built without it must be constructed with the same materials as that of the original house.

    It's not just about getting the green light from the city; you also have to comply with construction codes. Even if you don't get planning approval, you still need to submit a full set of plans or issue a building notice to ensure compliance with local codes.

    What You Should Know Before Building A House Extension

    What To Consider Before Building A House Extension3

    Who Am I Constructing It For?

    This is a crucial and frequently disregarded query. Far too often, people begin an expansion project without first clearly defining their goals.

    The project's success depends on your careful consideration of its intended audience and goals. For instance, do you have little children who are likely to remain at home for just a long period, or do you have older children who are more likely to leave home soon? Do you wish for them to move out permanently or just visit for a while? If you are nearing retirement and your children have flown the coop, you may be wondering if you really need all that additional room.

    Instead than just being a collection of concepts you've seen before, your design concept should take into account the specifics of your own life. By answering these questions explicitly, you'll be well on your way to crafting a thorough brief that will help you avoid wasting money on unneeded features and amenities.

    Do We Have Enough Room To Grow?

    You'll have to consider your own requirements to provide an appropriate response to this enquiry. The addition of a single bedroom might not have much of an impact on the amount of land you have available for a backyard, but adding a new family room and updating the kitchen could be far more significant extensions.

    Using rope or even other markers, you may begin to visualise the potential amount of space required by outlining the dimensions of the new sections on your property. To determine the appropriate size for each room, consider the current room sizes. Then take a step back and evaluate whether or not the remaining area meets your needs.

    Determine What You Want

    You need to know exactly what you want out of your extension, which may sound like stating the obvious. Adding a room onto the back of the house can increase the property value, but it won't be worth it if the room isn't utilised to its full potential.

    To get started, picture what your house may look like with more room, and then evaluate some options for a back addition. Determine what improvements an addition could make to your home or how it would mesh with the existing layout. It's important to keep in mind that you can change the function of the existing rooms in your home by adding on.

    Request Permission

    Any significant improvements to your property will require approval before you can begin. It's important to have a conversation with your municipal government has soon as possible once you begin planning an addition, as their input could ultimately determine the outcome of your idea. When you have a firm grasp on the permitted parameters, you may move on with confidence.

    Local governments aren't always strict about requiring planning approval, but they do enforce building codes. Instead of being let down when your dream idea turns out to be impossible, it's better to know these things up front.

    Employ An Architect

    The demand for an architect grows in proportion to the size of the project. If you plan to hire an architect, it's in your best interest to give them as detailed an explanation of your extension needs as possible.

    Simply by sharing your plans with an architect, both the concrete features of the addition and the more abstract ones, such as the way you see using the space, can be brought to life.

    It's a good idea to have an architect on hand for the duration of the construction process. They are qualified to communicate with contractors about the technical components of a project and can utilise their knowledge to alert you if construction is veering off track.

    Inform Your Neighbors

    It's certain that any major renovations you make to your home will have an impact on the neighbours, especially your immediate neighbours. Let them know what you have in mind from the get-go so you can gauge their reaction and adjust accordingly.

    If you have a conversation with your neighbours right away, you can prevent any tense situations from arising later. If you and the builders can't agree on how the construction will effect you and each other, you may have disagreements that escalate into disputes or even legal challenges.

    Obtain Several Quotes

    In addition to saving money, there are a number of other benefits to comparing rates. It's a chance to see the builders at work and get a feel for their methodology, so you can determine whether or not they'll be reliable and whether or not they'll utilise high-quality materials in your addition.

    Keep in mind that the construction crew will be living in your house for quite some time, so it's important to get along well with them. Though it's important to shop around, you shouldn't skimp to the point where your builders don't show up on time or don't believe in your vision again for addition.

    Can We Get More Natural Light And Heat?

    When adding on to an older home, one of the most important things to think about is finding ways to let in more natural light and heat, since these aren't usually hallmarks of the original design.

    If you've lived in your house for a while, you'll be familiar with the sun's path through the sky from season and where it enters the house depending on the time of day. If you're planning to build a living room or living area where you spend a significant amount of time, it's important to make sure that it faces north so that you can take advantage of the sun's warmth. Adding windows will let in more natural light, making the space warmer without turning up the thermostat.

    The exposure of the windows to direct summer sunshine, particularly the west-facing afternoon sun, is something to keep in mind if you plan on installing any additional large windows. Having sunshine flood into the room on a cold winter day is a pleasant result, but on a hot summer day, it might make the place unbearable. It is crucial at this point to have a solid grasp on orientation, choose glazing specifications that are well-suited to the environment, and make effective use of shade features. Having a professional architect or construction designer aid you will help you get the best results possible.

    Would We Have To Leave?

    There is no doubt that staying in the house during an addition will save you a significant amount of money, not to mention the hassle of having completely uproot your life & routine. This may not be as simple as it sounds. If the planned addition necessitates extensive remodelling of the existing portion of the house, living there during construction will be difficult. The project might be tiered in this case, allowing you to go from working on one area of the property to another.

    It's important to remember, though, that staging a construction project usually means it will take longer to build and, thus, cost a little more money.

    How Do I Locate A Builder?

    Getting referrals from people you trust is crucial when searching for a contractor. As was previously discussed, it's important to hire a contractor that has expertise working within a price range that's comparable to your own. If you need recommendations for reliable contractors, your construction design or architect should really be able to provide them. Some may even offer to manage the construction contract and serve as your representative on-site.

    In addition to searching online, you can ask for referrals from family, friends, and coworkers to narrow down your search for a reliable construction company. The most cost-effective contractor is usually the one who gets chosen in the end. If you're confident that each of the builders who provided estimates came up with the same number, then this is a satisfactory result.

    How Much Time Will It Take?

    If you were to measure a piece of string, how long would it be? An easy and speedy extension could take as little as four to six weeks. Take the case where you're merely adding a little amount of space beneath an existing roofline; in this case, you probably won't need a complete complement of tradesmen. If you were installing a new kitchen or bathroom, you could expect a similar schedule.

    However, this estimate is likely to be off by three to six months, given most additions feature a moist area. This is assuming, of course, that the extension has a respectable size. Additional time may be needed for major improvements to the actual building in addition to a substantial extension, especially if the latter requires construction on an upper story. Perhaps a time limit of from six to nine months is more reasonable.

    Home Additions

    Home extensions are typically labor-intensive projects that necessitate the assistance of professionals. It is possible to cut costs on an addition by acting as the owner-builder yourself.

    If you find that your family has outgrown your current home, adding on is generally a better option than moving. Expansions typically add more value to a home than they cost to build. But you need to weigh the hazards before making any investment.

    You should know these things before starting to construct an addition.

    Can I Make My Own Extension?

    Home extensions are typically labor-intensive projects that necessitate the assistance of professionals. It is possible to cut costs on an addition by acting as the owner-builder yourself.

    Extension For Owner Builders

    To cut costs, many homeowners who want to add on contemplate taking on the role of "owner-builder." Though it could help you save money, be aware that there are several potential hazards. Owner-builders have some duties that should be understood before going down this road.

    • A state owner-builder permit is required in most cases where remodelling costs more than $1000. Obtaining the licence can necessitate your spending your own money on a training programme.
    • When you're an owner-builder, you're in charge of the entire construction process. You are responsible for fulfilling all legal building obligations, such as obtaining contracts and permits, scheduling building inspections, and so on.
    • Owner builders must provide reports on a regular basis.
    • After finishing the project, you need to get all the appropriate building insurances, such as home warranty insurance.

    Collaboration With Contractors

    Talk to something like a local builder about the price of hiring them to construct an addition for you if you're on the fence about taking on the role of owner-builder. When these factors are considered, it may become clear that hiring a professional to manage your project is the best option.

    It's possible that you may manage the construction of a modest addition on your own, bringing in specialists if required. Professionals like architects and construction workers will be required for a larger project.

    Creating A Building Extension

    What To Consider Before Building A House Extension

    Extending your home, whether you do it yourself or hire professionals, requires a team effort in the form of planning and design. An architect or designer can make suggestions for home additions, but no action will be taken without your approval.

    Carefully plan out every step of the process before moving on. To ensure that your addition design is practical and suits your needs, think about how you spend your time and what you hope to achieve from the project.

    Don't forget to specify your ideal roofing, cladding, and interior finishing touches. These seemingly insignificant aspects will collectively result in a more precise cost estimate than like a per-square-meter estimate would.

    Obtaining Approvals

    A building permit is required for any extension, regardless of size, and in some situations, such as when rehabilitating a historic building, additional permits may be required. Find out what permits you need for your extension by contacting the local council or a reputable contractor to build it.

    It is also considerate to let your neighbours know what you're up to so that you may avoid any potential conflicts.

    Your Project's Financing

    Although adding on to your home is typically less expensive than purchasing a new, larger house, you should still plan carefully to avoid going over budget. In order to account for the possibility of unexpected costs, it is recommended that a 10% cushion be included to the final estimate.

    One of the benefits of constructing an addition instead of purchasing a new home is the ease with which one may acquire home equity financing. However, it's also simple to fall into the trap of taking on more debt than you can afford. The increase in value from your addition won't be felt until you decide to sell your property. Meanwhile, you must keep up with your regular monthly bills.

    When the plan is complete and the funds are in place, production may begin. Adding on to your home is less difficult than you would think if you take the time to carefully plan and budget for it. After it's done, you and your loved ones will take an increased pleasure in being at home.


    Extending a home has several benefits. Growing families need additional space. Building extensions take time and money. Thus, before diving in, there are considerations. Know what you want from a home extension.

    Determine how an addition would improve the layout or fit in. Remember that adding on can modify a room's function. Local governments must approve major house upgrades. When contemplating an extension, talk to them right away. Finding ways to let in more natural light and heat is crucial when expanding onto an older home.

    Staying in the house during an expansion saves money and the inconvenience of moving. If you outgrow your home, adding on is usually preferable than moving. Expansions usually add more value than they cost to develop. Owner-building an expansion saves money. Many homeowners consider "owner-building" to save money.

    Owner-builders have responsibilities. Most remodels above $1000 require a state owner-builder permit. An addition is cheaper than buying a new house, but you should still plan to stay within budget. The final estimate should include a 10% cushion for unanticipated costs. Your family will enjoy being home more after it's done.

    Content Summary

    1. Work, study, or exercise in a spare room.
    2. Considering a house addition? Consider these factors.
    3. Building extensions take time and money.
    4. 10 questions to ask yourself can get you started.
    5. You may require a building permit to expand your home.
    6. To comply with municipal codes, you must submit full plans or a building notice even if you don't gain planning approval.
    7. You must examine the project's audience and aims to succeed.
    8. Your design concept should reflect your life, not just a collection of ideas you've seen.
    9. To answer this question, evaluate your needs.
    10. Adding a bedroom may not affect your backyard space, but adding a family room and renovating the kitchen may.
    11. Outlining the new parts on your land with rope or other markings will help you visualise the area needed.
    12. Consider room sizes to calculate room sizes.
    13. Obviously, you need to determine what you want from your extension.
    14. If the room isn't used, adding a room to the back of the house won't raise its value.
    15. Imagine your house with more space, then consider back addition alternatives.
    16. Assess how an extension would enhance your home's layout.
    17. Additions might modify the use of your home's rooms.
    18. You need permission to make major property renovations.
    19. As soon as you start building an extension, go to your municipal government because their involvement could make or break your idea.
    20. Local governments enforce building codes but not always planning approval.
    21. Project size increases architect demand.
    22. If you're hiring an architect, explain your extension needs in detail.
    23. Share your designs with an architect to bring the addition's tangible characteristics and more abstract ones, like how you'll use the space, to life.
    24. An architect should be present during construction.
    25. Major home renovations will affect neighbours, especially your immediate neighbours.
    26. Talking to your neighbours right away can avert future conflicts.
    27. Remember that the building workers will live in your house for a while, so get along with them.
    28. Shop around, but don't skimp so much that your builders don't show up or don't believe in your addition concept.
    29. Since older homes sometimes lack natural light and heat, adding more to them requires creative ways to bring these in.
    30. If you've lived in your house for a while, you'll know where the sun enters the house at different times of day and season.
    31. Make sure your living room faces north to take benefit of the sun's warmth.
    32. Windows bring in natural light, warming the room without raising the temperature.
    33. Using a skilled architect or construction designer will improve your results.
    34. Staying in the house throughout an addition will save you a lot of money and the aggravation of uprooting your life and routine.
    35. Living in the house during construction will be challenging if the planned expansion requires considerable remodelling.
    36. Staged construction projects take longer and cost more.
    37. Finding a contractor requires trusted referrals.
    38. As mentioned, you should pick a contractor with experience in your pricing range.
    39. Your construction design or architect should propose trusted contractors.
    40. To choose a dependable construction company, you can search online and ask family, friends, and coworkers for suggestions.
    41. The lowest-cost contractor usually wins.
    42. Assuming the extension is large.
    43. Owner-building an expansion saves money.
    44. Many homeowners considering adding on consider becoming "owner-builders" to save money.
    45. Most remodels above $1000 require a state owner-builder permit.
    46. Training for the licence may cost you.
    47. Owner-builders oversee all construction.
    48. Get house warranty insurance and other building insurances after finishing the project.
    49. If you're considering owner-building, ask a local builder how much it would cost to build an extension for you.
    50. These variables may suggest employing a professional project manager.
    51. Planning and designing an extension, whether you do it yourself or employ specialists, takes a team.
    52. Consider how you spend your time and what you want from the project to create a viable expansion.
    53. Include your prefered roofing, cladding, and interior finishes.
    54. These seemingly minor factors will result in a more accurate cost estimate than a per-square-meter estimate.
    55. Contact the local council or a trustworthy contractor to build your expansion to see what permissions you need.
    56. Plan carefully to prevent going over budget while building on to your home, which is usually cheaper than buying a bigger one.
    57. The final estimate should include a 10% cushion for unanticipated costs.
    58. Home equity borrowing is easier for additions than new homes.
    59. Your addition won't enhance value until you sell.
    60. Maintain your monthly bills.

    Frequently Asked Questions About House Extension

    There are always exceptions to the rules; however, in general, the majority of house extension building projects follow a similar process:

    • Site Establishment. 
    • Demolition/Groundworks/Drainage. 
    • Build structure/Roofing/External Finishes. 
    • Internal Renovation and Remodelling. 
    • Services, Internal Fitout and Finishes.

    For rear extensions

    • Single-storey rear extensions can be extended as far as 4m for detached houses and 3m for other houses. This can increase to 8m and 6m, respectively, with prior approval.
    • Double-storey rear extensions can go as far as 3m from the original house as long as it's more than 7m away from the rear wall.

    Detached House Extension Rules 2022

    Under permitted development for a detached house, you can extend up to 4m under permitted development and up to 8m under the larger home extensions scheme / prior approval.

    A Step By Step Guide To Adding An Extension Onto Your Home

    • Step One: Do Your Research. 
    • Step Two: Planning Permission. 
    • Step Three: Building Regulations. 
    • Step Four: Find an Architect. 
    • Step Five: Find a Builder. 
    • Step Six: Move Out.

    Planning permission for extensions

    An addition or extension to your house* is generally considered a permitted development. So, you won't need to go through the additional hassle of getting planning permission as long as: Your extension is no more than half the area of land around the original house (curtilage).

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