Broadly speaking, there are two types of building firms that are likely to want to take on a private building project. The first and most popular is a small firm of registered builders. Such firms exist all over the country and form the mainstay of the private building industry. Labour is usually organised by the owner of the firm, most appropriately referred to as a contractor. The contractor looks after the business side of the firm, provides quotes, agrees contracts, manages the work, holds the National House Building Council (NHBC) registration if they have any, and so on.
Contractors tend to have relatively few overheads. They usually hire in plant and machinery as they are required for each job and rarely have many full-time employees, preferring instead to subcontract the work to individual tradespeople, employed on a freelance basis. With so few overheads, contractors are often able to offer the most competitive quote, although quotes can vary dramatically from one contractor to another.
Although only likely to be interested in larger projects such as the construction of a new home, you can choose to employ a larger registered building company. Such an organisation might have a regional or even a national chain of offices. They will probably have some full time employees, at least at management and administrative levels, and are likely to own all necessary plant and equipment. Consequently, the larger firm will tend to charge more than the smaller one in order to cover their additional overheads. For the additional cost though, clients have the comfort of dealing with what should be a highly professional, efficient and reliable organisation that will ensure a very high build quality, at the cost that was quoted.
There are various ways to utilise the services of a builder on a private building project. A builder can be used in conjunction with an architect, surveyor or other project manager who will administer the building contract and inspect the work as it develops. Ideally, this should be the professional who designed the project as they will be familiar with the specification. Alternatively, the individual self-builder can choose to manage the contract themselves, only engaging an architect or surveyor to certify the work as it is completed. The full service from an architect, to include design and contract administration, will usually be charged on a percentage basis, starting at around 7%. Using an architect or surveyor only for inspections will cost considerably less.
For those building their own home, a builder can be used to provide all the labour, materials and equipment required to complete the project, all under a single contract. Alternatively, a builder can be used in conjunction with a package supplier, for instance with a timber frame company or traditional package supplier who may provide some or even all of the materials required to complete the project. Another option is to use a builder to construct the shell of the house only, leaving the remainder of the project - usually the internal trades - to be completed by individual tradesmen or DIY labour.
Before finalising your choice of builder, obtain quotes from at least three firms in order to be able to make a comparison. When asking for quotes, be sure to specify exactly the same terms to each firm by attaching the plans for your project and the specification. It is not easy for builders to be accurate about the cost of everything, but ask them all to make the same standard assumptions. For example, on a new house, no-one accurately knows the cost of the foundations until work starts, so ask them to assume that a normal concrete strip foundation will be required, this way, when comparing the different quotes, you will at least be comparing like with like.
Also when there are details in the design that have not yet been decided - for instance the type of kitchen/bathroom/heating system/decorative finishes etc - make sure that each builder is being asked to allow the same provisional sum for these costs. These are often referred to as prime cost or PC sums in a quote. As a final check, insist on seeing one of the builder's previous works of the same scale. Ask for references - no reputable firm should have any problem asking previous clients to provide a reference if they are happy with the service they have received.