So, What to Know Before Building a House Extension
Planning a house extension is an exciting step that can transform your living space and add long-term value. However, before any building work begins, it’s important to understand what’s involved. From budgeting and planning permission to design choices and builder selection, each stage plays a part in your project’s success.
In this guide, we’ll explore what to know before building a house extension, including essential steps, common challenges, and practical advice to help you get started.
Understand Why You’re Extending
Before deciding on the size or type of extension, ask yourself why you’re doing it. Are you looking for more space, better functionality, or improved property value? Common reasons include:
- Creating an open-plan kitchen and living area
- Adding a bedroom or home office
- Increasing natural light or garden access
- Avoiding the costs and stress of moving house
Having a clear purpose will help guide your decisions and keep your project on track.
Budgeting for Your Extension
Budget is often the first factor to consider. Costs vary based on size, location, materials, and design. Typically, a single-storey extension can range from £1,500 to £2,500 per square metre. Factors that impact the final cost include:
- Groundworks and foundations
- Roofing materials
- Interior finishes (e.g. flooring, lighting, heating)
- Planning and design fees
- Structural changes to the existing property
If you’re unsure how much to budget, contact us for a clear, itemised quote tailored to your needs.
Check Planning Permission Requirements
Not all extensions require planning permission. Under permitted development rights, you can make certain changes without full approval. However, you’ll need to follow strict size and layout guidelines, and not all properties qualify.
It’s best to confirm early by reviewing GOV.UK’s planning guidance or speaking to your local authority. We also offer planning support to ensure your build meets all regulations.
Choose the Right Type of Extension
There are many extensions to choose from, each with different benefits:
- Single-storey rear: Ideal for larger kitchens or dining areas
- Side return: Makes use of unused alley space
- Wraparound: Combines rear and side extensions
- Double-storey: Adds bedrooms and bathrooms
- Loft or garage conversions: Efficient use of existing space
The right choice depends on your space, layout, and goals.
Find Experienced Builders
Your choice of builder is one of the most important decisions. Look for:
- Strong reviews on sites like Trust a Trader
- A portfolio of past projects
- Insurance and relevant accreditations
- Transparent contracts and timelines
At We R Builders, we’re known for reliable, high-quality results across Kent and offer full construction and new build services.
Be Aware of Timelines
A standard extension project may take 3–6 months, depending on complexity, weather, and material availability. Allow extra time for:
- Design and planning
- Building control approval
- Structural calculations
- Any unforeseen site issues
We recommend building a buffer into your schedule and maintaining regular communication with your contractor.
Think Long-Term
When planning your extension, think beyond immediate use. Will the layout still work in five years? Will it appeal to buyers if you choose to sell?
Features like underfloor heating, good insulation, and practical storage all help create a more future-proof design. Once the project is finished, our aftercare team ensures everything continues running smoothly.
Renovations and Layout Changes
In many cases, an extension goes hand-in-hand with internal renovations. You may need to knock down walls, relocate utilities, or reconfigure the ground floor to make the most of your new space.
Early planning for structural work will avoid delays and ensure your layout flows seamlessly.
Final Thoughts
A successful house extension starts with careful planning and expert support. By understanding your needs, budget, and responsibilities, you can build a space that works for your lifestyle and adds long-term value.
For advice or to get started, contact us for a free consultation. We R Builders has a proven track record of delivering quality projects across Kent, from extensions to full construction services in Kent.