Extending Your Home in the South West

Extensions are a popular means of improving a home by adding additional space for a larger family or improving facilities such as the kitchen or living space. With the variety of properties found in the South West, from cottages and farmhouses to terraced townhouses and modern houses, a range of planning considerations from design to construction need to be taken into account. With a good clear sequence of steps, many of the unforeseen challenges can be overcome.

Understanding Your Needs

Start with a brief. What is the living situation of the household, what is not working and what will you need in the future? Think about how the new space will connect to and relate to the existing space, how will daylight move through the space and relate to the garden and outdoor space? Leave the end design open to options.

Understanding The Property

Each plot has its own set of constraints. There is a wide range of variability in the soil conditions of the South West from clay and shale to sandy soil and granite. Topography and slope impact the use of a site and limit what can be built. Existing trees and drainage further restrict options. Surveying the existing property and surrounding site and doing an early investigation of site conditions can give the design team options and allow the team to address potential issues in the design.

Site conditions must also be considered. The South West of England can have strong winds and driving rain. Elements of the design that consider the building’s resistance to the surrounding climate need to be incorporated at the beginning of the process. This can include roof overhangs and the use of durable materials and detailed joints.

Planning Permission and Other Approvals

Before beginning building works, you will need to have permission from the local planning authority, unless the works can be performed under permitted development rights. These rights do not apply to all areas, for example, a protected or conservation area, or the build is within a national park. There are also limitations to permitted development rights which you should check before designing your extension.

Separate to these planning regulations are the building regulations, which set standards for building works including the structure, fire and other safety measures and the facilities provided. The Act also grants protection to neighbouring properties, and thus, you may need to notify your neighbours of your building works and send them a Party Wall Notice.

Choosing the Design Team

Most homeowners engage an architect, architectural technologist, or design-and-build company for the extension works. Your designers should be able to show you case studies, and explain how they will undertake the various approvals. Responsibilities of the various parties should be clarified. A structural engineer will be needed for the design of beams and foundations, and other specialist consultants may be needed such as an ecologist to check the site for protected species.

Design Development

During design development sketches are refined and executed to scale. This is when the position of windows and the type of materials used are decided. The location of heating and ventilation is determined, and the exterior appearance of the extension from the street is designed.

The extension will be built to passive house principles, and during design development the placement of insulation, glazing and ventilation will be designed in order to create a comfortable and usable space throughout the year. Overheating and summer comfort will also be designed into the extension.

Selecting a Builder

Drawings are given to the builders, outlining the work to be done. The builders provide a fixed price for the work. The builder must have previously done similar work, and have references and completed projects. The contractor is responsible for arranging the necessary insurance for the work.

Preparing for the Build

Access to the site must be arranged, and the owner must decide where building materials will be stored, as well as where skips will be located. The owner must decide which rooms will not be accessible, and how building materials will be moved through the site to the working area. In narrow, congested streets of the area, a strategy to time deliveries may need to be created.

The Construction Process

Different components of the construction process may occur in a different order at different stages. The general sequence is site setup, demolition (if any), excavation, foundations, walling, weathertight structure (roof and openings), first fix (services and waste routes), insulation and plaster, second fix (doors and skirtings), decorations, floorings, etc.

Completion and Handover

The final work is inspected for small defects. These include a stuck or binding door, caulk or touch-up paint on a wall, etc. Gather warranties, building completion certificates, gas and electric certificates, building operations manual and other documents. It is vital to have these documents when selling the house.

An extension, if designed and planned well, rewards one's patience with the process. Good planning, communication and site information facilitates design approvals early, contributing to a successful outcome.