Choosing designers, engineers and builders

The people you hire decide how good your finished building will be. A careful choice now saves you from poor work, delays and disputes.

By the end, you will understand the main roles on a project. You will also be able to compare quotes and agree clear written terms.

Who does what

Different professionals handle different parts of a project. On a small job, one person may cover several roles.

• An architect or building designer turns your brief into drawings and plans.
• A structural engineer makes sure the building can safely carry its weight and resist forces such as wind.
• A quantity surveyor or cost consultant estimates costs and checks bills.
• A main contractor, or general contractor, runs the building work and manages other workers.
• Subcontractors are specialists hired by the main contractor, such as electricians, plumbers and roofers.
• A project manager plans and supervises the whole project for you.

You do not always need all of them. Ask a designer or engineer which roles your project really needs.

How to find good candidates

Start with people who have done similar work. Ask friends, neighbours and other owners for names. Visit finished projects if you can.

In many places, some trades and professions need a licence or registration. Ask each person what qualifications or registration they hold. Then check with the relevant professional body or government office where you live.

You can also look for designers, engineers and builders on our professionals page.

Get and compare quotes

A quote is a written offer to do a job for a stated price. Ask at least three builders to quote for the same brief and drawings.

Compare quotes line by line, not just the total. Look at what is included and what is left out. A very cheap quote may leave out key items, use poorer materials or lead to extra charges later.

Ask each builder how long the work will take and when they can start. Also ask who will be on site each day.

Ask the right questions

Before you choose, ask every candidate a few simple questions:

• Can I see recent similar work and speak to past clients?
• Do you hold insurance for injuries and damage during the work?
• Who buys the materials, and can I see the prices?
• How do you handle changes and extra costs?
• What guarantee do you give on your work, and for how long?

Clear, confident answers are a good sign. Vague answers or pressure to decide quickly are warning signs.

Agree everything in writing

A written contract protects both you and the builder. It should list the work, the price, the start and finish dates and the payment stages.

It should also explain how changes are agreed and priced. A change agreed during the work is often called a variation. Include how disputes will be handled and what happens if the work is late.

Contract law varies by country. Ask a local lawyer to read any contract before you sign, especially for large projects.

Common mistakes

• Choosing the cheapest quote without checking what it includes. Compare every quote line by line.
• Relying on a spoken agreement. Put the work, price, dates and payment stages in a written contract.
• Not checking past work. Always visit or ask about recent similar projects.

Key points

• Know the main roles so you hire only the professionals your project needs.
• Compare at least three quotes for the same brief, line by line.
• Agree the work, price, timing, payments and changes in a written contract.