What you should know when renovating

Renovating your home is exciting but can cause a considerable amount of inconvenience, mess and stress. Whether you’re renovating to add comfort, or to sell, a Master Builder will help you through every step of the process.  

In a renovation or alteration, your existing building's construction may not be understood until part way through the building process. So, you may need to make compromises to work with what already exists.

Unlike a new build, when you renovate or extend a building you may have to compromise your design to work around what already exists.

In a renovation or alteration, you are working with an existing building. You should factor in that you might:

  • not have the original plans
  • not have plans that reflect what was built, or any other renovations
  • not be able to understand parts of the existing structure until your build starts (for example, inside walls)
  • want or need to keep existing features
  • need to retrofit items (for example, insulation or windows)
  • need to meet additional requirements for the whole building, even if you are only altering part of a building (for example, smoke alarms)
  • need to meet additional requirements if you are changing the use of the building, such as, means of escape from fire, access and facilities.
Matching existing materials, finishes and tolerances (how much the work varies from stated measurement) may be difficult or even impossible in renovations or extensions.

It is important to be conscious of common issues that can arise when matching old and new materials. For example, older existing building materials will likely be machined or manufactured in imperial sizing where new materials often have a smaller finished size as they are manufactured to metric dimensions. This is typically an issue with materials such as weatherboards, skirting and scotia.

Because of the complexities of renovating, the project may take longer and may cost more than building new.


With a few exceptions, major work is going to need building consent. The building consent application will require plans and specifications to be attached. Your Master Builder can prepare these for you.


Do you need to hire a designer?

Whether you need a designer to design and draw up plans depends on the extent of work being done. 

If you are having a bathroom or kitchen renovated, you can use the specialist services of kitchen and bathroom designers. Some offer a design service only, but others can offer a service which includes all or some of the following:

  • A consultation at your home
  • Bathroom/kitchen design service
  • Strip out of existing fittings
  • Installation of new fittings
  • Plumbing work
  • Electrical work
  • Paint and paper finishing
  • Complete tile services
  • Payment and finance options


Do you need to hire an engineer?

With some renovations and major alterations, you will need the services of a chartered professional engineer.

Engineers are necessary when you are extending up or out, or when you are removing structural elements. They can also provide specialised advice on other parts of the project.

Your builder or architect should let you know if an engineer is required and what the extra costs will be. Or you can contract one directly by looking online or getting referrals from other people.

Our Master Builders will help you through these steps. Find a Registered Master Builder.


Plan renovation projects carefully

The first steps in planning a renovation is to collect ideas and information from books, websites, social media, magazines and brochures. A great place to start is the House of the Year website where you will see the best new homes and renovations across all budgets and categories. 
Work out a budget and decide what is achievable and what is not. It is also a good idea to plan the project room by room. You will also want to consider the future and how your needs may change over time.


Planning for a specific project

Consider whether you can realistically live in the house while the work is being done. If you are planning major work, such as adding another story, it might be sensible to move out while work is underway. 

Seek legal advice  

We strongly recommend all homeowners get independent legal advice when entering into a building project, including a renovation. Your lawyer should review your building contract and your guarantee.  They should take you through both your contract and the guarantee to ensure you know your rights and obligations, as well as those of your Builder or Master Builder. Ideally find a lawyer who has some experience with construction projects, as they will be best placed to explain the contracts to you and identify the key risks that you face.    

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