So, What to Expect During a House Extension?
Planning a house extension can be exciting, but knowing what to expect during a house extension helps you prepare for the process and avoid unexpected surprises. Whether you’re extending your kitchen, adding an extra bedroom, or creating more living space, understanding each stage of the project ensures a smooth and stress-free experience. With years of experience in home extensions, I’ve guided homeowners through every step, ensuring their projects are completed efficiently and to the highest standard. In this blog, I’ll break down what to expect from start to finish when undertaking a house extension.
Step 1: Planning and Design
Define Your Goals
Before construction begins, it’s essential to outline what you want to achieve with your extension. Consider:
- How much extra space you need
- The purpose of the extension (e.g., additional bedroom, home office, open-plan kitchen)
- Your budget and how much you’re willing to invest
Planning Permission & Regulations
Many extensions fall under permitted development rights, meaning they don’t require planning permission. However, larger or more complex projects may need approval from your local authority.
Your extension must also comply with building regulations covering:
- Structural integrity
- Fire safety
- Insulation and energy efficiency
Architectural Design & Drawings
An architect or a professional designer will create detailed plans that suit your needs while ensuring compliance with regulations. This includes:
- Layout and structural drawings
- Electrical and plumbing plans
- Visual concepts of the finished extension
Step 2: Budgeting and Cost Estimates
Understanding Costs
House extension costs vary based on size, materials, and complexity. On average:
- Single-storey extensions: £1,200–£2,500 per square metre
- Double-storey extensions: £1,500–£3,000 per square metre
Additional costs may include:
- Architectural and planning fees
- Structural engineer assessments
- Fitting and finishing costs
Getting Quotes from Builders
Request detailed quotes from Trust a Trader and Google My Business verified builders to ensure you’re getting competitive pricing. A good quote will break down:
- Labour costs
- Materials
- Estimated project timeline
Step 3: Preparing for Construction
Finalising Permits and Contracts
Once planning permission (if required) is approved, contracts should be signed with your builder to outline:
- The agreed scope of work
- Payment schedules
- Expected completion dates
Preparing Your Home
Before construction starts, you may need to:
- Clear out rooms that will be affected
- Protect furniture and belongings from dust and debris
- Make alternative living arrangements if necessary
If your kitchen or bathroom is affected, consider setting up a temporary space to minimise disruption.
Step 4: Construction Process
1. Site Preparation and Foundations
The first stage of construction involves clearing the site and laying foundations. This includes:
- Excavating the area for foundations
- Pouring concrete and allowing it to set
- Preparing drainage and utilities
2. Structural Work and Walls
Once the foundation is in place, builders will construct the walls and install structural supports. This stage includes:
- Brickwork or timber framing
- Insulation installation
- Windows and doors fitted
3. Roofing and Weatherproofing
The extension must be made weatherproof to protect against rain and external conditions. This involves:
- Installing the roof structure
- Fitting tiles or waterproofing materials
- Ensuring insulation is properly placed
4. Internal Works and Services
Once the shell of the extension is complete, work moves inside. This phase includes:
- Electrical wiring and plumbing installation
- Heating and ventilation systems
- Plastering walls and ceilings
5. Flooring and Fixtures
As the extension nears completion, finishing touches are added:
- Flooring (tiles, wood, or carpets)
- Fitting kitchen units, bathroom fixtures, or built-in storage
- Painting and decorating
Step 5: Inspection and Approval
Building Control Checks
Before completion, the work must be inspected to ensure it meets building regulations. An inspector will check:
- Structural safety
- Electrical and plumbing installations
- Insulation and energy efficiency
Final Touches
Once approved, your builder will carry out any last adjustments, including:
- Snagging (fixing minor defects)
- Final cleaning of the site
- Handing over all necessary documentation
How to Minimise Disruptions During a House Extension
1. Set a Realistic Timeline
House extensions typically take between 8–16 weeks, depending on complexity. Keep communication open with your builder to track progress.
2. Maintain Good Communication
Regular updates from your builder will help you stay informed about any delays or unexpected challenges.
3. Plan for Temporary Living Adjustments
If major parts of your home are affected, consider temporary arrangements to make daily life easier.
Why Choose Us for Your House Extension?
With years of experience delivering high-quality house extensions, we ensure your project runs smoothly, stays within budget, and meets all safety regulations. Whether you’re looking for a single-storey extension, a loft conversion, or a complete renovation, we provide expert craftsmanship from start to finish.
Contact us here to discuss your house extension project. You can also check out our verified reviews on Google My Business and Trust a Trader to see what others say about working with us.