How Long Does a Home Extension Take? Timeline Breakdown

One of the most frequent questions we receive at V3 Build is regarding the duration of a project. While every home in Newton Abbot, Exeter, or Torbay presents unique challenges, a standard single-storey extension generally takes between 3 to 5 months of active construction.

However, the build itself is only one part of the journey. Understanding the full timeline—from the initial concept to the final coat of paint—is essential for managing your expectations and living arrangements.

Phase 1: Pre-Construction (3 to 6 Months)

This phase often takes longer than the actual build. It involves the legal and design groundwork required before any physical work can begin.

• Design and Planning: Working with an architect to finalize drawings and submitting them for planning permission usually takes 8 to 12 weeks. Local authorities in Devon typically aim to decide on applications within 8 weeks.

• Technical Drawings and Calculations: Once planning is granted, a structural engineer must produce calculations. This stage takes approximately 2 to 4 weeks.

• Party Wall Agreements: If you have shared boundaries, you must give neighbors two months’ notice before work begins.

• Tendering and Scheduling: Reviewing quotes and securing a slot in a builder’s diary can take several weeks, as reputable firms like V3 Build are often booked months in advance.

Phase 2: Groundworks and Shell (4 to 8 Weeks)

This is the most transformative and weather-dependent part of the project.

• Excavation and Foundations: Digging the trenches and pouring concrete typically takes 1 to 2 weeks, depending on the soil conditions and the depth required by Building Control.

• Damp Proofing and Oversite: Installing the damp-proof membrane and pouring the concrete floor slab takes about 1 week.

• Wall Construction: Building the internal and external leaves of the walls takes 2 to 4 weeks.

• Roof Structure: Constructing the roof and making it “watertight” with felt, batten, and tiles adds another 1 to 2 weeks.

Phase 3: First Fix and External Finishes (2 to 4 Weeks)

Once the shell is watertight, the focus shifts to the internal infrastructure and the external look of the building.

• Windows and Doors: Installation usually takes 1 to 2 days, though lead times for ordering these can be 6 to 12 weeks.

• First Fix Services: Electricians and plumbers install cables and pipes behind the walls.

• External Rendering: If your extension requires render or cladding, this is usually applied now, provided the Devon weather remains dry.

Phase 4: Second Fix and Internal Finishes (4 to 6 Weeks)

This is the stage where the extension begins to feel like a home.

• Plastering: Plastering the walls and ceilings takes about 1 week, followed by a mandatory drying period of at least 1 week before any decoration can start.

• Second Fix Services: Fitting sockets, switches, radiators, and sanitaryware.

• Flooring and Carpentry: Installing internal doors, skirting boards, and the final floor finishes.

• Kitchen/Bathroom Fitting: This is often the most time-consuming part of the interior work, taking 1 to 2 weeks.

Phase 5: Snagging and Sign-off (1 to 2 Weeks)

The final stage involves a thorough inspection to ensure everything meets the high standards of V3 Build and the requirements of Building Control.

• Snagging: Addressing minor cosmetic touches or adjustments.

• Final Inspection: A Building Control officer visits to issue the Final Completion Certificate, which is a vital document for any future property sale.

Estimated Timelines by Project Type

Factors That Influence the Schedule

Several local variables can shift these timelines. Coastal locations in Torbay may face stricter regulations or harsher weather delays. Similarly, renovating an older property in a conservation area like Newton Abbot may require more careful, time-consuming construction methods.

At V3 Build, we use our 25 years of local experience to provide realistic, honest timelines, ensuring your project moves forward efficiently without compromising on quality.