From concept to completion

We always aim to be open and honest with our clients and involve them in the process, ensuring they have a good understanding of the work they’ve commissioned.

Initial meeting & Project Brief

A meeting with a design consultant is arranged. The feasibility of a project is tested against the likely building cost, the structural requirements and regulatory limitations. By the end of the meeting it is usually clear what direction the project will take.

Preliminary Measure & Design

The design consultant returns to refine the ideas previously considered, and to measure and photograph the house. This information is used to create a 3D computer model. The designer sets about resolving the best possible balance of aesthetics, efficiency, and detailing.

Presentation & Agreement

The design consultant returns with floor plans, a perspective rendering, a set of specifications and the project cost. The client can now see exactly how the extension would look and how well it meets the project brief. The client now agrees to sign up to an agreement authorising Duncan Thompson Extensions to prepare working drawings and a building contract.

Site Visit & Working Drawings

The new clients now meet the managing director, the estimator, the geo technician and the structural engineer. Draftsmen re-measure the house to confirm the accuracy. We are then able to develop working drawings from the approved extension design. Some minor amendments are usually made on the client’s request and included in the final documentation after their approval.

Contract Signed

A final set of drawings, specifications and the contract are delivered to the client for approval. With the design, specifications and price already confirmed, there are no surprises and we are usually able to proceed to the contract stage with confidence.

Home Extension Building Permit Issued

We now obtain Home Owner’s Warranty insurance and the building surveyor issues the building permit. The project manager meets with the client to discuss details such as access to the site and the schedule of works. Building materials are ordered and tradesmen assigned to the project.

Work On-Site Commences

Projects involve the use of many trades such as scaffolding, concreting, carpentry, bricklaying, plumbing, electrical, plastering, tiling, and roof tiling. Despite this, clients can frequently live comfortably at home while construction continues.

Notice of Completion Issued

All extension timeframes are different, but a number of months after work on site begins a project is complete and a notice of completion is issued by the building surveyor.

Related Information

Home Extension Costs

One thing almost everyone wants to know is how much a home extension costs. This is a difficult question to answer, but here we explain what factors determine the cost of an extension.

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There are a number of factors outside of our control, however we’ve completed so many over the last 30 years that we have a pretty good idea how long it takes to build an extension.

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We offer fixed-price home extension contracts which include design, planning approvals and construction. The contract details everything, with costings, so there are no nasty surprises.

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Project Management

Your Building Supervisor will be onsite every step of the way to ensure everything runs smoothly. They are your day-to-day contact and will facilitate any requirements you may have.

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Building Inspections

During every home extension a series of inspections are carried out to ensure all aspects of the construction have been implemented safely and within mandatory building requirements.

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Our people, from the front office right through to the onsite trades have worked with us for many years. This continuity of people ensures a smooth workflow during every extension we build.

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Building Permits

We’ll determine what permits and planning approvals are required to build an extension to your home. We negotiate with Councils on your behalf so there’s nothing you need to do.

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Building Insurance

Every home owner should ensure they have adequate insurance on their home before they start an extension. We can assist you if you have concerns about your level of cover.

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