The length of time it will take to complete your home extension will depend on a number of factors including the size of the development work, and whether or not you are planning to live in the house when work is carried out.
For a single storey extension, it will normally take around 3 months for the work to be completed.
The first step in the process is for the site to be prepared. It usually takes around 2 weeks to dig out the footings and prepare the foundations, and then a further 2 weeks to install the damp course and any drains that are needed around the extension.
By week 5 of the process, your builders will normally be working on the external walls and putting in place blockwork to provide cavity wall insulation. Ties would be used to integrate the new brickwork into your existing walls.
The next two weeks will usually be devoted to fitting the roof structure and internal walls.
At this point, the structure will need to be made weather proof which is when your Independent Network Installer should be on site fitting your new uPVC windows and doors.
From this point on, electricians or gas fitters will need to be on site to add power to the extension. This fit will be followed by the plastering of internal walls and breaking through into your existing house.
Once the plaster is dry and decorating has been completed - and any units or furniture fitted, your extension will be ready to use.
A two storey extension will normally take a few weeks longer depending on the complexity and size of the project.