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A double-storey extension refers to a type of building expansion that adds two floors to an existing property. It extends the ground and upper floors, seamlessly blending with the existing structure.
In the United Kingdom, double storey extensions have become widely popular in the real estate industry. Landlords and private property companies often choose this option due to its advantages.
For instance, a double storey extension increases the size of a property by providing needed additional space for homeowners. This space can be utilised as home offices, bedrooms for growing families, or a gym room. It significantly enhances both the appeal and functionality of the property.
Mostly double storey extensions focus on expansion achieved through reconfiguration and redesigning existing floor plans. This allows for the incorporation of living space, ensuring comfort and convenience in one's home.
Another significant benefit is that a double storey extension tends to increase the valuation of the property. The current high demand for homes in the UK contributes to this trend regarding property value.
A designed property with a two-story extension has a market value because it attracts investors and buyers interested in property investments that offer the potential for maximising their return on investment (ROI).
How Much Does a Double Storey Extension Cost?
In the United Kingdom, the average cost of a double storey extension varies depending on factors. While homeowners can expect to pay an estimated range of £50,000 to £100,000 as a baseline cost, it's important to note that these figures are approximate and actual costs may vary based on factors such as the property's location.
The location plays a role in determining costs. For instance, properties in cities like London, Cambridge, Oxford, Bristol, and Edinburgh tend to have values and associated costs compared to properties in more affordable regions like Derby or Nottingham.
Another factor influencing the double storey extension cost per m2 is variations in labour and material expenses. Labour costs are higher in cities across the UK but relatively cheaper in some areas. Additionally, project complexity and material prices also contribute to costs.
Types of Extension & Prices
| Types of Extension | Average Cost (£) |
|---|---|
| Standard quality double storey extension per sqm | £1850 |
| Good quality double storey extension per sqm | £2050 |
| Excellent quality double storey extension per sqm | £2560 |
| Extension planning drawings cost | £960 |
| Foundations based on 60m2 double storey (30m2 per floor) | £6050 |
| Framing based on 60m2 double storey (30m2 per floor) | £36150 |
| Roofing based on 60m2 double storey (30m2 per floor) | £14150 |
| Surveyors fees | £1350 |
| Party wall agreement | £800 |
Construction Cost
Construction costs include excavation, foundation work, walls, roofing, windows, doors, and flooring. These costs depend on factors like the scale of the project, material expenses, and labour fees for workers such as bricklayers, carpenters, plumbers, tilers, electricians, and painters. All these aspects contribute to determining the construction costs.
| Construction Element | Cost Range (£) | Unit |
|---|---|---|
| Excavation | Varies | Based on site |
| Foundation | 1,500 - 3,000 | per metre |
| Walls | 40 - 150 | per square metre |
| Roofing | 50 - 100 | per square metre |
| Windows | 500 - 1,200 | each |
| Doors | 100 - 500 | each |
| Flooring | 20 - 100 | per square metre |
Architectural Design Cost
The cost of hiring an architect can vary based on factors such as their experience, reputation, and the size and complexity of the project. The timeframe for project completion can also impact the architecture costs.
Budgeting for these fees when planning a two-story building is essential. Some architects may have a fee structure for medium-sized projects. However, for larger-scale projects, many architects charge a percentage ranging from 7.5% to 15% of the construction fee. Architects and designers may also charge between £75 and £125.
| Architect Service | Average Cost Range (£) |
|---|---|
| Single Storey Extension Planning Application | £1,500 – £2,500 |
| Double Storey Extension Planning Application | £2,500 – £3,500 |
| Single Storey Extension Building Reg & Construction Drawings | £4,000 – £5,000 |
| Double Storey Extension Building Reg & Construction Drawings | £5,000 – £6,000 |
| Loft Conversion Planning Application | £1,000 – £2,000 |
| Loft Conversion Building Reg & Construction Drawings | £2,000 – £3,000 |
| New Build Planning Application | £4,000 – £5,000 |
| New Build Building Reg & Construction Drawings | £6,000 – £7,000 |
Planning Permission and Regulations
In the United Kingdom, obtaining planning permission from authorities is necessary before constructing or making alterations to a property. This includes seeking approval from planning authorities and health safety executives in the UK
If your extension requires planning permission, you should consider the associated costs of submitting an application and obtaining approval. This may involve paying fees to the planning authority. Additionally, adhering to building regulations and acquiring permits and inspections may result in expenses.
Material Cost
The cost of materials plays a role in determining the expense of building a double storey extension. High-quality materials like premium flooring, windows, and features will increase the cost.
Material costs can vary depending on the region and availability. When deciding which materials to use for your construction project, it's important to consider cost, long-term durability, and maintenance requirements.
Labour Cost
The labour cost includes wages and benefits paid to construction workers. This expense also varies depending on factors such as location, job complexity, working hours, and the experience of workers. Skilled tradespeople like builders and contractors often charge rates based on their expertise in handling double storey extension projects.
The daily labour rates for tradespeople typically range from £150 to £250. It's important to remember that additional professionals such as electricians, landscapers, or plumbers may also be required, adding to the labour expenses.
In total, the estimated work costs for a 30m2 two-story expansion range from £26,000 to £30,400. Expanding the area by 60 m2 would require an estimated labour cost of £40,000 to £44,000. Extending it by 100 m2 would amount to £54,000, to £60,000 in labour expenses. When faced with decisions, it is always recommended that you obtain quotes to ensure you get the most reasonable price for the labour involved.
Additional Expenses
When undertaking a double storey extension construction project, costs might be considered beyond the main construction work. Some of these costs include:
Interior Finishing
This encompasses interior design elements like fixtures like built-in wardrobes and closets, light fixtures, chandeliers, central heating systems, radiators, kitchen cabinets, and countertops.
It may also involve fittings like:
- Sofas
- Chairs
- Dining tables
- Refrigerators
- Washing machines
- Ovens
- Curtains and blinds
The cost of these finishes can vary significantly depending on factors like quality standards, style preferences, and design complexity.
Exterior Works
Besides the finishes mentioned above, work-related costs should be considered. This includes tasks related to the finishing touches of landscaping that's necessary for the construction of a double-story extension.
Estimating the cost of these works may involve garden design, paving, fencing, driveway construction, or any other modifications needed for the existing property. The overall cost mainly depends on the project's size, complexity, and the materials used in construction.
Insurance and Warranty
To developed countries, insurance is a crucial aspect to consider in the UK when dealing with construction projects. It's important to have insurance coverage during the extension project's construction phase.
This helps protect against events like accidents, property damage, or even theft of materials. Additionally, professional contractors often provide warranties for their work as a testament to their confidence in its quality.
This offers homeowners peace of mind and protection against any defects or issues that may arise after completing the project. When planning your budget, you must include insurance and warranty costs in your project expenses.
Unexpected Expenses
It is essential to allocate a contingency budget for emergency costs that were not initially accounted for in the construction cost of the double story extension.
Emergencies can arise unexpectedly during a construction project, such as issues or the need for additional work to meet new UK building regulations or changes to the overall project scope. To be prepared for such situations, allocate around 10% to 20% of the project cost as a buffer.
Tips for Saving Costs
Here are some tips to help you save money:
Thoughtful Planning and Design
Take consideration in planning and designing your extension to make the most of space and functionality. You can minimise the need for structural modifications and changes during construction. Factors like layout, room sizes, and natural light flow should be considered for optimising space utilisation.
Compare Quotes from Sources
Obtain quotes from contractors and suppliers to compare prices and ensure you're getting the best value for your money. However, don't solely focus on cost savings: also consider the reputation and experience of professionals involved, as quality should be maintained.
Consider Standard Materials
While choosing end or custom materials may be tempting, opting for materials can significantly reduce costs without compromising quality. Standard materials are often more affordable and readily available. You could explore alternatives that offer appeal and functionality at a lower price point.
Explore Other Options
Explore using hand or reclaimed materials for parts of the extension, such as doors, windows, or fixtures. This can help reduce costs without compromising on quality. Could you ensure the materials are in good condition and meet the safety standards?
Put in Place Energy Efficiency Measures
Make your extension design energy-efficient by incorporating features like insulation, energy-efficient windows, and LED lighting. Although there might be a cost involved in implementing these features, they can lead to long-term savings on energy bills.
DIY Elements
If you have the time and expertise, consider taking on the role of project manager yourself. This involves coordinating and overseeing aspects of the project like scheduling, hiring subcontractors, and managing the budget. However, please be aware of the complexities involved and ensure you have the skills to manage the project effectively.
Depending on your skill level and experience, you may be able to handle DIY tasks during the project to save on labour costs. However, it's important to assess your abilities and only take on tasks you are confident about completing to a standard.
DIY Elements
When considering a double storey extension, you can do tasks like painting, landscaping, or simple interior finishing. However, before deciding to take on these DIY elements, it's important to consider their feasibility and the potential costs involved. Here are some factors to keep in mind:
Feasibility:
Assess Your Skills
Look at your skill level and experience in the specific tasks you're considering doing yourself. Some tasks like painting or basic landscaping might be more doable for a DIY approach. Others, like plumbing work, may require professional expertise. You can only tackle tasks you feel confident in accomplishing to a standard.
Time and Availability
DIY elements can be time-consuming, especially if you have commitments like work or family responsibilities. Consider whether you have the time to dedicate to the project. Be realistic about how long each task will take and whether it fits within your schedule.
Tools and Equipment
Determine whether you have all the tools and equipment for the DIY tasks. Remember that purchasing or renting tools could increase costs, so factor this into your budget. Make sure you have a grasp of how to use the tools effectively.
Cost Considerations:
Quality
One thing to consider when doing DIY projects is the cost of compromising quality. While DIY can save money, ensuring the work meets the standards and regulations is important.
If DIY work is poorly executed, it may require repairs or fixes in the future. If you need more clarification about your ability to achieve professional-level results, hiring a professional for those tasks might be worthwhile.
Time and Delays
DIY projects sometimes take longer than professional work. This can lead to project delays, especially if certain tasks must be finished before others can proceed. Delays can affect other aspects of the project and may result in added costs or inconvenience.
Warranty and Insurance
Another cost consideration is that DIY projects may have no warranty or insurance coverage. Professionals typically offer warranties on their work, which protect in case of defects or issues. Additionally, insurance coverage during construction may not cover DIY work, meaning you would be responsible for any damages or accidents.
Building Regulations
Ensure that any DIY work follows building regulations and permits. Not following these rules may lead to penalties, and redoing the work can be expensive and time-consuming.
It's essential to remember that although these suggestions can help cut down on expenses, it is vital to maintain the quality and safety of the extension. Before deciding to handle do-it-yourself components, carefully consider their feasibility and cost implications.
If you are still determining your skills or the complexity of tasks, it is advisable to seek advice from professionals or hire them for those aspects of the project.
Property Values for Double Storey Extension
Adding a double storey extension to your property can impact its value. Not only does it provide additional living space, but it also enhances the overall visual appeal of the property. Below, we will explore how a double storey extension can influence property value and the long-term financial advantages it brings:
Increased Livable Area
One of the main advantages of a double storey extension is the addition of livable space. This can include bedrooms, bathrooms, a larger kitchen, or even a spacious living area. The increased square footage and improved functionality make the property more appealing to buyers, boosting its market value.
Enhanced Functionality
By incorporating more rooms and improving the layout of your home, a double storey extension greatly enhances its functionality. This is especially attractive to families or individuals seeking additional space to cater to their needs effectively. Improved functionality aligns with modern lifestyles and contributes to increasing property value.
Elevated Visual Appeal
A well-designed double storey extension that integrates with the existing architecture results in an enhanced overall visual appeal of your property.
The cohesive integration creates an upgraded appearance that adds value through improved curb appeal. A double storey extension can significantly impact the value of your property by enhancing its appeal and making it more attractive to buyers.
The Long-term Financial Benefits
Energy Efficiency Improvements
Adding energy-efficient features to your double storey extension can bring long-term financial benefits. This includes installing insulation, energy-efficient windows and LED lighting. These upgrades reduce energy consumption, resulting in lower utility bills over time. Moreover, eco-friendly homes are increasingly attractive to buyers, which adds to the appeal of your property.
Potential Rental Income
Sometimes, a double storey extension creates an opportunity for additional income. Extra bedrooms or a self-contained unit can be rented out, providing a source of income. This additional income potential enhances the value of your property and offers buyers the option to generate extra income.
Market Demand
The demand for properties with additional living spaces is often high in areas where land is limited or expensive. A double storey extension helps distinguish your property in the market and attracts interested buyers. The increased demand can drive up the value of your property over time and provide a good return on investment.
It's worth noting that the actual impact on property value will vary depending on location, market conditions, construction quality, and the demand for properties in the area. It can be valuable to seek advice from real estate experts who can provide insights into how a double storey extension might affect property value in your market.
In general, a well-planned and executed double storey extension can significantly increase property value. It not only adds space but also improves functionality and offers long-term financial benefits through energy efficiency enhancements and potential rental income.
FAQs
Q: What size extension can I build without planning permission?
A: You are more limited with a double-storey extension, but you are still able to build without planning permission if you stay within the specific guidelines. For all the recent guidelines, check out the Planning Portal website.
Q: How long does planning permission take for an extension?
A: Most applications are completed within eight weeks. However, if they're large or complex projects, they may take longer - this may take up to thirteen weeks.
Q: How much value will an extension add to your property?
A: A double-storey extension can add as much as 15% to the value of your property. This will depend on size, location and quality.
Sources
https://urbanistarchitecture.co.uk/double-storey-extension/
https://interactive.planningportal.co.uk/mini-guide/extensions-two-storey/