Single Storey vs Double Storey Extensions: Which is Right for You?

Understanding Single Storey vs Double Storey Extensions

Choosing between a single storey and double storey extension is one of the most important decisions you'll make for your house extension project. Both options offer unique benefits and challenges, and understanding the differences is crucial for making an informed decision that suits your needs, budget, and property.

Single Storey Extensions: Overview and Benefits

Single storey extensions add space on the ground floor level, typically extending your kitchen, dining room, or living space. These extensions are often more straightforward to design and construct, making them popular choices for families looking to create open-plan living areas or expand their kitchen space.

Key Benefits of Single Storey Extensions: Lower construction costs per square meter, simpler planning requirements, faster construction timeline, and easier integration with existing ground floor spaces. Single storey extensions also typically have fewer structural requirements and can often be built under permitted development rights.

Ideal For: Kitchen extensions, open-plan living areas, dining room expansions, and ground floor bedroom additions. Single storey extensions work particularly well for properties with good garden space and families who want to create seamless indoor-outdoor living.

Double Storey Extensions: Overview and Benefits

Double storey extensions add space on both ground and first floor levels, significantly increasing your home's living space and value. These extensions are more complex but offer substantial benefits in terms of space creation and property value enhancement.

Key Benefits of Double Storey Extensions: Maximum space creation, significant property value increase, efficient use of plot space, and ability to create additional bedrooms and bathrooms. Double storey extensions also provide better cost per square meter ratios for larger projects.

Ideal For: Growing families needing additional bedrooms, properties with limited garden space, and homeowners looking to maximize their investment. Double storey extensions are particularly valuable in areas with high property values where space is at a premium.

Cost Comparison and Budget Considerations

Single Storey Extension Costs: Typically range from £1,500-2,500 per square meter, with total costs often between £30,000-80,000 depending on size and specifications. These extensions benefit from simpler construction methods and fewer structural requirements.

Double Storey Extension Costs: Generally range from £1,800-3,000 per square meter, with total costs often between £60,000-150,000 depending on size and complexity. While more expensive per project, they offer better value per square meter of additional space.

Budget Factors: Consider not just construction costs but also planning fees, building regulations costs, and potential impact on existing services. Double storey extensions may require more extensive work to existing structures and services.

Planning Permission and Building Regulations

Single Storey Extensions: Often fall under permitted development rights if they meet specific criteria regarding size, height, and location. This can significantly reduce planning costs and timelines. However, properties in conservation areas or with restrictive covenants may still require full planning permission.

Double Storey Extensions: Almost always require full planning permission due to their impact on neighboring properties and local character. The planning process is more complex and may require additional reports such as daylight and sunlight assessments.

Building Regulations: Both types of extensions must comply with building regulations, but double storey extensions have additional requirements for structural stability, fire safety, and sound insulation between floors.

Construction Timeline and Disruption

Single Storey Extensions: Typically take 8-16 weeks from planning approval to completion, with construction often completed in 6-12 weeks. These extensions cause less disruption to daily life as they don't affect upper floors during construction.

Double Storey Extensions: Generally take 12-24 weeks from planning approval to completion, with construction often taking 10-20 weeks. These extensions may require temporary accommodation arrangements during construction, particularly if they affect existing bedrooms or bathrooms.

Disruption Considerations: Consider how construction will affect your daily routine, especially if you work from home or have young children. Single storey extensions typically cause less disruption to existing living arrangements.

Property Value and Investment Considerations

Single Storey Extensions: Typically increase property value by 5-15% depending on local market conditions and the quality of the extension. Kitchen extensions often provide the best return on investment in terms of both value and lifestyle benefits.

Double Storey Extensions: Generally increase property value by 10-25% depending on local market conditions and the additional space created. These extensions often provide better long-term investment returns, particularly in areas with high property values.

Market Considerations: Research local property values and buyer preferences in your area. Some areas may favor single storey extensions for their lifestyle benefits, while others may value the additional space provided by double storey extensions.

Making the Right Choice for Your Property

Assess Your Needs: Consider your current and future space requirements, family size, and lifestyle preferences. Think about how you use your home and what type of additional space would most benefit your daily life.

Evaluate Your Property: Consider your plot size, existing layout, and potential for different types of extensions. Some properties are better suited to single storey extensions, while others may benefit more from double storey additions.

Budget and Timeline: Be realistic about your budget and timeline constraints. While double storey extensions offer more space, they require larger budgets and longer timelines. Single storey extensions may be more achievable for tighter budgets or shorter timelines.

Professional Advice and Next Steps

Consulting with experienced house extension specialists can help you make the right choice for your specific property and requirements. Professional advice can help you understand the full implications of each option and ensure you make an informed decision that maximizes both your investment and lifestyle benefits.

Whether you choose a single storey or double storey extension, working with experienced professionals ensures your project is designed and executed to the highest standards, providing you with additional space that enhances both your property value and quality of life.