Planning and budgeting are essential steps for anyone looking to build, extend, or adapt their home or business premises.
Planning a house extension is an exciting step for many homeowners, but one of the most important — and often overlooked — aspects of the process is the building contract between the homeowner and the builder.
A clear written contract protects both parties and helps ensure the project runs smoothly from start to finish.
Without a written agreement, misunderstandings can easily arise about costs, responsibilities, changes to the work, and how problems should be resolved.
A written building contract:
Several standard forms of domestic building contract are commonly used in the UK for house extensions and residential alterations. The three most frequently encountered are outlined below.
This is one of the most widely recognised construction contracts in the UK and is often used where architectural drawings and specifications have been prepared for the project.
The contract allows an architect or designer to act as Contract Administrator. In that role they can certify interim payments, instruct variations, assess delays, and confirm practical completion.
It also includes a defects rectification period during which the builder must return to correct any issues that arise after completion.
Because it provides structured procedures for payments, variations, and extensions of time, it is often preferred on projects where a professional consultant is administering the construction phase.
The JCT Home Owner Contract was specifically designed for residential clients and is written in simpler language than many traditional construction contracts.
Two versions exist:
For many domestic extension projects, the HO/B version is perfectly adequate where the homeowner intends to manage the relationship with the builder directly.
This contract is commonly used where the builder is a member of the Federation of Master Builders.
It provides a straightforward written agreement covering:
It is generally used on smaller domestic projects where the builder manages the construction process and the client deals primarily with the builder rather than through a contract administrator.
At Misbourne Design Associates Limited, our primary role is to assist clients with the design, planning, and technical aspects of their extension projects.
We do not automatically administer domestic building contracts unless specifically requested by the client.
Our experience over many years has shown that most homeowners prefer to deal directly with their chosen builder once the design work and approvals are complete.
For that reason, the contract we most commonly recommend for domestic extension projects is the JCT Home Owner Contract HO/B. This allows the homeowner and builder to enter into a clear written agreement while keeping the administration straightforward.
Where a client prefers a more formally managed construction process, a JCT Minor Works contract with a contract administrator can also be considered.
Entering into a written building contract is one of the most important steps when undertaking a house extension.
It protects both the homeowner and the builder and ensures there is a clear understanding of:
Selecting the appropriate contract will depend on the size and complexity of the project and the level of professional involvement the client wishes to have during construction.
Planning and budgeting are essential steps for anyone looking to build, extend, or adapt their home or business premises.
Making the most of your available space is key to creating a home or business premises that is both practical and inviting.
