How much are the architect fees for an extension?

Quick architect fees for an extension guide

Use this guide to get a better idea of the architect costs for your new extension. Find out how the size will affect costs, as well as some top cost-saving tips to help you make the most of your budget.

We'll cover the following topics in this cost guide:

1. Average architect costs for an extension
2. What services do architect fees include?
3. Small vs large extension architect fees
4. Top cost-saving tips for architect fees
5. Long-term benefits of hiring an architect
6. Find an extension architect near you on MyBuilder
7. FAQ: Common questions about extension architect costs

Average architect costs for an extension

Architects don’t just draw up plans, they design spaces that are both functional and beautifully tailored to your lifestyle. From securing planning permission to navigating building regulation costs, an architect helps smooth out the most complex stages of your extension build.

Typically, architect fees for extension projects are calculated as a percentage of the overall construction costs, ranging from 5% to 15%.

Take a look at the average architect fee costs for an extension:

Extension type	Architect fees
Single-storey extension	£3,000 – £8,000+
Double-storey extension	£5,500 – £12,000+
Loft conversion	£3,000 – £7,000+
Basement extension	£8,000 – £15,000+

Don't forget: To get the best price possible for your extension project, just post your job on MyBuilder then connect with multiple verified architects in your area. You can then discuss the job, get advice, request quotes etc.

What services do architect fees include?

Architect fees usually span several stages, each playing a vital role in turning your ideas into a successful build.

During the design stage, your architect develops the core concepts that define how your new space will look and function. Planning fees depend on how detailed the drawings and documentation need to be for approvals and applications.

Take a look at the different services an architect will offer for your extension build:

• Conceptual design: Establishing the initial vision. Cost: £1,000 - £3,000
• Detailed design: Developing precise plans and specifications. Cost: £3,000 - £6,000
• Planning application: Preparing and submitting necessary documents. Cost: £500 - £1,200, depending on complexity and local requirements
• Building regulations drawings: Creating detailed architectural drawings to meet legal standards. Cost: £3,000 - £5,000

Don't forget: The intricacy of the design and choice of materials can substantially influence fees, so discussing these elements with your architect is wise to mitigate unexpected costs.

Small vs large extension architect fees

Fees vary by extension size for several reasons. A larger extension typically requires more comprehensive services, including detailed planning and extended project management.

Take a look at how the size of your extension could affect architect fees:

• Project complexity: Large projects often involve more intricate designs, necessitating extensive planning and drawing efforts.
• Scope of work: Larger projects require more hours from architects, explaining the fee discrepancy.
• Design specifications: Customised design features in both small and large projects can increase costs, but their relative impact is greater on smaller extensions.
• Duration of project: Longer projects may involve extended oversight, leading to higher fees for large extensions.

If you want to know how much your extension will cost from start to finish, read this full extension building cost guide too.

Top cost-saving tips for architect fees

Successfully negotiating architect fees can significantly impact the total cost of your extension project.

To do this, it’s important to be clear about your budget and the work you need done.

Here is how:

• Understand clearly what you need from the architect to tailor your negotiations effectively.
• Request a detailed breakdown of the fees to comprehend each cost component. Compare multiple quotes on MyBuilder to ensure competitive pricing.
• Ask about discounts or packages for combined services to save costs.

MyBuilder-Tip: To compare quotes for your project, just post your job on MyBuilder today. Then, architects near you who are interested in the job can respond, without you having to spend hours conducting the entire search yourself.

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Long-term benefits of hiring an architect

Hiring an architect for your house extension offers lasting benefits.

Their expertise and creativity can elevate your design, ensuring your new space is both practical and in harmony with your existing home.

**Here’s how an architect can make all the difference: **

• Improve your property value: A thoughtful design can make your home more appealing to future buyers.
• Make the space functional: Architects know how to maximise space and tailor layouts to your lifestyle.
• Create visual harmony: They ensure your extension complements the look and feel of your existing property.

Plus, they’ll make sure your plans meet all building regulations, helping you avoid delays, fines, or costly mistakes down the road.

If you want to know more about building regulations, see this full building regulations cost guide here.

Find an extension architect near you on MyBuilder

Planning a home extension or renovation and want to understand architect fees? Post your project on MyBuilder today!

It’s a quick and easy way to connect with local architects, compare quotes, read customer reviews, and find the right professional to bring your ideas to life, within your budget.

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FAQ: Common questions about extension architect costs

How do architect fees for an extension typically compare to the overall project cost?

Architect fees for an extension generally represent a percentage of the total project cost, often ranging from 5% to 15%. This proportion might vary based on the complexity of the project and the services included. For smaller, less complex projects, fees are relatively high compared to the overall cost, given the fixed amount of work involved.

What are the common methods architects use to calculate their fees for an extension?

Architects typically use several methods to calculate their fees. These include percentage-based fees, which relate to the project’s overall cost, lump-sum fees for defined work scopes, and hourly rates for more flexible projects. The chosen method often depends on the project type and client preferences.

What are the potential additional costs beyond the architect's initial fees for an extension?

Beyond an architect's initial fees, you might encounter additional costs such as planning permission fees, building regulations application fees, structural engineering assessments, and construction material costs. Be sure to discuss potential extras with your architect to better anticipate the overall financial outlay.

How does the complexity of an extension impact architect fees?

The complexity of an extension significantly impacts architect fees, as more intricate projects necessitate greater time and expertise. Complex projects might require detailed planning, additional consultations with specialists, and customized solutions. These factors often translate to higher fees.