Planning an extension is no less challenging than building a house from the ground up; and if you’re not a professional project manager or builder, it can be a daunting task with so many moving parts. There’s a lot to consider and plan, but after a decade in the building business, I still believe the most important aspect to any successful project is knowing what you want and keeping that in mind throughout the entire project.
To start with, it’s important to consider what you want from your extension and what its ultimate purpose will be. Before you speak to a builder or even a project manager or surveyor, decide exactly what construction work you require. If you have a clear idea of what you’re looking for and what you want as your end result, you can provide an extremely clear brief for them, and they’ll then be able to give you a more accurate estimate of timescales and costs.
There’s also no point considering any building work until you know your home is structurally stable and safe. Simple things, like having bowed floorboards looked at, gaping cracks addressed, damp-proofing done – they’re all necessary and help to make sure your renovation goes more smoothly later down the line. Consider hiring a structural engineer to produce a building report which will give you a solid base to start from.
These planning steps means your builders will be more likely to produce work you’re happy with and ultimately keep the project on time and on budget. Planning really is key for any project, so make sure you do your research and plan ahead. If you know your builders will need access, make sure they have it; if you think you’ll need to move out of the home whilst the construction takes place, make sure you have somewhere to go etc. All small things like this should be considered at the beginning to make the process as easy as possible.
Finally in the planning stage, have in mind a rough idea of what your top budget is before you begin speaking to any project developers, builders or contractors. And don’t just consider the work itself – additional costs, such as professional fees and any new decorations you’ll want to finish the space – they all need to be factored in at the beginning to ensure the entire project is achievable. It’s always worth having a small buffer too, in case any unexpected costs are incurred during the build.
Once you have confirmed your house is structurally sound and you’ve done your research, you should look to book an appointment with a surveyor, who will visit your property and assess what’s needed. An experienced surveyor will take the appropriate measurements and sketches of your space, whether that is a loft, kitchen or basement space. The initial survey can take at least an hour, so leave yourself with a block of time to sit down with your surveyor and go over all the finer details.
Your surveyors should then provide you with a detailed overview of how your project will look and function, and any necessary steps you need to take to get to that completed state. This will provide the basis for the project, and though prices could potentially fluctuate slightly, this should give a good indication as to the final amount of work.
The next step is for your surveyor to pass their detailed quote and floorplan sketches to your architectural team, who will start to create the architectural plans needed for your project – if you do not already have architectural plans in place.
Your architect will then be in touch with you about the specific elements of your project, and they will advise you on whether your project needs planning permission from your local council. If your project requires planning permission, you will also all need to submit your detailed plans to obtain this, or if your project falls under permitted development, you will need confirmation of this from your local planning authority with a certificate of lawful development.
Before construction can begin, you will also need to obtain any relevant party wall agreements. Once you have obtained your party wall agreements and received approval from your local council (if needed), you will then need to assign your building team.
To ensure your builder is fit for your job, ask what similar projects they’ve carried out previously. And be sure to ask for testimonials from previous customers. Be cautious if they can’t provide you with customer testimonials, as most reputable builders will have these in spades. Additionally, you want to ensure you choose a builder who’s had a high percentage of their work pass Building Regulations.
At this point, you should also speak to your builder about realistic timeframes and any other ongoing commitments. If your builder is working on several projects at once, it means they’re not giving your job their full attention – and this can seriously delay your work being completed and then have a negative impact on other contracted tradespeople, such as plumbers, carpenters, or plasterers.
This is now the stage when your project will begin to be constructed by your assigned building team, with payments needing to be made at various milestones. Realistically, it’s several weeks for a small one-storey extension or a loft conversion, to six months for a double-storey extension, comprising several rooms. It’s important that you keep this in mind as the build progresses, because, at this stage, you don’t want anything holding up your project. It’s likely your building team will start with your outer structure, then your internals and finally your roof to seal the project.
Once the bulk of your project is completed, you will be asked to complete a snagging list, which will be a list of checks you want your building team to go through before they sign off on your project. Once happy with your finished project, your project will be signed off by building control, and you will be issued with a completion certificate and, depending on your builders, warranty or guarantee paperwork for your new space.