House extensions: The Ultimate Guide
Learn MoreLast week, my sister called to ask for some advice about architects’ fees.
Her friend was planning to build a relatively simple single storey rear extension and a loft conversion and had approached four architects to obtain quotes.
All very normal so far….
However, upon receiving their fee proposals, she was shocked that the fees ranged from £2,000 to £15,000.
Wow! I was as amazed as her.
How is this possible I hear you ask? How much does an architect charge in the UK?
The answer to this question on architects’ fees is not straightforward. So below, I’ve done my best to explain all the different factors which might affect how much an architect might charge in 2022.
Table of Contents
- 1. Architects fee structures explained
- 2. Apart from drawings, what else will your architect help with?
- 3. Apart from architects’ fees, what other costs do I need to consider?
- 4. How can I keep architects’ fees down to a minimum?
- 5. Will my architect understand the planning policies?
- 6. How much does an architect charge for Building Regulations?
- 7. How much does an architect charge to prepare a tender pack?
- 8. How much does an architect charge for construction inspections?
- 9. Architect fees for project management
- 10. Are there different types of Architects?
- 11. How to make sure you are hiring a real architect
- 12. How to agree your architects’ fees
- Conclusion
1. Architects fee structures explained
1.1. A percentage of the project costs
This type of fee structure is better for medium to large scale projects where neither the architect nor the client know exactly what they’re looking for.
The client’s brief could be quite broad, for example ‘I would like the biggest possible house the planners will allow.’
At the start of a project, it’s hard to know exactly what kind of design, height, width or depth planners might allow. It’s therefore difficult to know the scale of the project and ultimately what the architects’ fees will be.
In this situation, fees can be calculated as a percentage of the final build cost. From a client point of view, the bigger and more lavish the final design, the more fees you would expect to pay your architect.
If you’re wondering how much does an architect charge, it will typically range between 2% – 15% of the total project cost.
In general, the larger the project the lower the percentage.
1.2. By the hour
Paying for an architect’s time on an ad-hoc basis is useful when you’re clear on what needs to be done but not clear how many hours a particular piece of work might take. For example, if you are about to begin building a new house and have agreed for your architect to carry out weekly on-site inspections to check progress, it would be difficult for your architect to know how much time they will spend during each visit. In this case an hourly fee is the best structure for architects’ fees.
On average, qualified architects in the UK will charge between £100 and £200/hour.
1.3. A fixed fee
A fixed fee structure is great for smaller projects such as extensions. This fee structure means the client gives their architect a very clear brief about what they’re looking for.
For example, you may want a two-storey rear extension or a loft conversion. In my opinion, this is the best of all three options because it offers you as the homeowner peace of mind. This is because you know that halfway through a project your architect couldn’t suddenly say ‘this project is far more complicated than I thought, we would like to increase our fee’.
A fixed fee structure prevents that from happening, which is why we believe this is the best structure to work with for smaller scale projects.
Extension Type | Concept & Design | Planning | Building Regulations |
---|---|---|---|
Single Storey Extension | £1,200 – £1,400 | £100 | £1,200 – £1,400 |
Extension + Loft Extension | £1,700 – £2,000 | £100 | £1,700 – £1,800 |
New Build House | £4,000 – £6,000 | £800 | £4,000 – £6,000 |
Here is a breakdown of the work involved in each stage.
1.4. Concept and Design
1. Measured Survey: Most architects will use a 3D laser scanner which is the fastest and most accurate way to capture both the inside and outside dimensions of your house.
2. Design Meeting: Your architect might arrange a shared screen meeting with you to run through your design ideas. They can also discuss your budget requirements, planning routes and timescales.
3. Preliminary Drawings: This is where your architect’s creativity and experience shines. They will design a full set of 2D and 3D plans, bringing all the ideas from your design meeting to life.
4. Revisions: Once you have reviewed the plans, your architect will arrange another screen sharing session where we can go through your feedback. They can then make any necessary changes to make sure the plans are perfect.
5. Final Issue: Once you agree the final set of plans, they will be submitted to your local planning authority.
1.5. Planning
1. Submission: Your architect will complete the relevant forms and submit your application along with your drawings.
2. Planning Fee: You will receive a link from the Planning Portal to make payment for the submission. These might not be included within your architects’ fees so double check with them.
3. Validation: The council validation team will make sure all the plans are correctly labelled and that all relevant forms have been completed accurately. Your architect will let you know when this happens.
4. Planning Officer Review: The assigned planning officer will review all the submitted documents and plans.
5. Decision: This is when both you and your architect would celebrate as your plans will have been approved!
1.6. Building Regulations
1. Detailed drawings: Your architect will create a full set of technical drawings to show that your plans comply with the relevant British Standards.
2. Choosing professional consultants: Once the technical drawings have been prepared, your architect can introduce you to a structural engineer (or you can use one of your choice).
3. Consultant assessment: Once you have chosen an engineer, your architect will provide them with the technical drawings. They can then prepare their own structural calculations and drawings.
4. Revisions: The structural engineers will then send their drawings and calculations to your architect to be checked.
5. Submission: Now, the technical drawings can be submitted to building control so it’s time to find a builder.
2. Apart from drawings, what else will your architect help with?
When you’re trying to find the answer to ‘how much does an architect charge?’, it’s key that you know exactly what will be included in that price. In addition to drawing up your plans, your architect will play an important role in:
Creative ideas: Your architect will have a huge amount of experience and will have worked on lots of different projects. If you’re not 100% sure what you’re looking for, they’re great at preparing lots of different options of layouts or designs for you to choose from.
Planning advice: Architects should have a good understanding of local planning policies. They will be well placed to take your ideas and advise whether there may be any conflicts with planners. If there are, they will be able to design creative solutions to overcome any hurdles.
Planning administration: Your architect will also manage the entire planning process on your behalf. That will include completing all the relevant application forms, submitting plans, and also liaising with the planning officer during the course of your application.
Building regulations administration: The building regulations process can be a little more complex than planning, as it requires more input from external consultants such as structural engineers and party wall surveyors. Your architect will be able to liaise with these consultants and manage the entire process on your behalf.
Problem fixing during construction: Even the simplest of extensions can raise unexpected problems on site which need to be quickly rectified. You architect will always be on hand to provide any advice to both you and your builder should problems arise during construction – all included in the architects’ fees.
3. Apart from architects’ fees, what other costs do I need to consider?
3.1. Planning Application
Planning application fees are approx. £240.00 which would be paid via the Planning Portal.
Once your application fee has been paid, your local authority will automatically be sent all your submitted documents and plans.
3.2. Structural Engineer
Extension Type | Structural Engineer Fees |
---|---|
Single Storey Extension | £800 – £1,200 |
Extension + Loft Extension | £1,300 – £1,700 |
New Build House | £6,000 – £10,000 |
Once your architect has prepared a set of detailed drawings, those plans would then need to be sent to an engineer.
Your engineer will prepare a full set of structural drawings and calculations to make sure your extensions are all adequately supported.
3.3. Party Wall Surveyor
Extension Type | Party Wall Surveyor Fees |
---|---|
Single Storey Extension | £900 – £1,200 |
Extension + Loft Extension | £1,200 – £1,500 |
New Build House | £1,500 – £1,800 |
The above fees are simply averages and can be affected by several different factors, including:
- The size of your property
- Complexity of the architectural design
- The number of surveys required
- The level of risk of damage to the neighbouring property
- Any negotiation required
4. How can I keep architects’ fees down to a minimum?
4.1. Have clear ideas
Although architects are very good at being creative, it’s important you give them a clear brief before the project starts. For example, you should let them know your exact budget. Do you like open plan living? Do you have a Pinterest board full of materials you like that you can share? Wondering how much does an architect charge can be complex, but having clear ideas will help them offer you a more accurate quote.
The more information you give your architect to work with at the start of your project, the fewer revisions and changes there will be later. Fewer changes mean your architect will charge you lower fees.
4.2. Set a clear budget
Architects can have very grand plans. They can design you a fantastic zinc clad rear extension with bespoke roof lights, but these designs can be expensive. Before the design process starts, you should calculate your total budget for the entire project and also leave a little left over as a contingency.
If your architect has a good idea of your budget at the start of your project, you can be confident the final design will be delivered as expected.
4.3. Prepare a schedule of works
Depending on the fee structure, architects sometimes work on a percentage of the total build cost. This means that the higher the total construction cost the higher your architects’ fees will be.
The best way to obtain a very accurate picture of the total construction cost is to obtain a ‘schedule of works’ or ‘bill of quantities’ from your architect or a quantity surveyor. That document will be specific and will include things like: How many bricks will your extension use? How much cement? How many light fixtures will you need? etc.
If you receive that document back and the build cost is higher than expected, you can then run through the list with your architect. They can help you cost save, which would in turn lower their fees.
5. Will my architect understand the planning policies?
Design Focus: The typical route to become an architect involves five years studying at university and completion of a minimum of two years’ practical experience. During that time, architects focus mainly on design. Architects spend far less time focusing on planning policies.
But isn’t it strange that the people who assess your architect’s design are not architects themselves? In fact, your local planning authority will employ lots of planning officers whose job it is to have a detailed understanding of all the relevant planning policies (rather than architects).
Planning Expertise: This is where the use of a planning consultant can come in handy. For example, at Adara, half our team are former local authority planning officers. This means we have a great understanding of all the relevant planning policies. Our planners work closely with our architects and clients to make sure all our designs are granted planning approval.
6. How much does an architect charge for Building Regulations?
Planning Permission vs Building Regulations Approval: Planning permission is granted when your local planning authority considers that your proposed design meets all the relevant local policies.
Building Regulations on the other hand is a separate process where an inspector will check to see whether your detailed designs are safe to build and meet all the relevant British Standards.
Do I need both? The short answer is yes.
Your architect’s fees should include one stage for drawings required to obtain the planning permission.
The second set of drawings you will need will be a detailed set of plans sometimes referred to as ‘working drawings’. These will look similar to your planning drawings but will include lots of construction information such as: Steel beam dimensions, size and depth of foundations, and the specific type of insultation required. Once prepared, these plans will either be sent to your local authority or to an approved inspector who will check them for accuracy.
Will my architect charge me extra fees for detailed drawings? Your original fee proposal should include a fee for planning drawings and building regulations drawings. In our experience, those two fees should be similar to one another.
If your architect is charging £1,200 to prepare planning drawings for a simple extension, their fee to prepare the detailed drawings should be similar. It takes a similar number of hours to prepare both sets of drawings.
7. How much does an architect charge to prepare a tender pack?
This depends on the project’s complexity.
Smaller extension projects: If you’re proposing a simple single storey rear extension or loft conversion, paying additional fees to an architect to package up your detailed drawings, structural engineer’s calculations and specification of works is not always necessary.
This process is very easy to manage on small scale projects and involves you finding a few builders you like, whether it be through a Google search or recommendations from friends or family. If you send those builders all the relevant documents, they should then be able to send you a fixed fee for construction.
Larger Extension projects: Larger renovations including multiple extensions, new roofs or even a new house are more complex. In these instances, we think it’s always a good idea to ask your architect to manage that process on your behalf as the construction’s costs will be higher.
8. How much does an architect charge for construction inspections?
Smaller extension projects: As above, for smaller scale projects, there is less need to pay additional fees to your architect for regular construction inspections. If you choose a reputable builder and the extensions are relatively straightforward, there will rarely be major issues on site that your architect would need to deal with.
It’s also worth remembering that Building Control Inspectors will arrange regular visits to site at pre agreed intervals with your builder, to check that your extensions are being built in accordance with the relevant standards and plans.
Larger Extension Projects: This category would apply to new houses or extension projects that include rebuilding a large proportion of your home, e.g. a wrap-around two storey side and rear extension. Larger projects are always more complex and we would expect more unforeseen circumstances during your build.
In these cases, we feel it is a good idea to pay your architect for regular site visits to check progress each week. If any issues are flagged, your architect can discuss them with both you and your builder to work out a solution.
9. Architect fees for project management
What is Project Management? Full project management involves paying your architect a fee to manage the entire tender and construction process on your behalf. The advantage is that it gives you peace of mind, but bear in mind your architect will charge additional fees for the service.
Smaller extension projects: When it comes to small scale extensions, most reputable builders are more than capable of managing the entire process on your behalf. In these instances, we don’t think it’s necessary to pay additional fees for your project to be managed.
Larger Extension projects: Larger scale projects are more complex. There is far more work involved, more tradespeople, and the project will take longer.
With these types of project, project managers can be invaluable as they are experts in managing the construction process efficiently. Not only can they assess your builders’ work, but they will have very good time management skills to make sure your project is completed on time.
10. Are there different types of Architects?
The term architect is quite broad, but this large pool can be split into three different categories.
10.1. Traditional Architects
Advantage: Depending on the size of practice, these companies will have lots of employees with complementary skills. They may have some architects who are great at design, and others who specialise in detailed drawings for building control. They often also have in-house planners or designers who can prepare incredibly realistic CGIs showing what your extension will look like once built.
Disadvantage: In some instances, although you may be dealing with an architect with years of experience, in reality the drawings might be prepared by a junior architect with less experience, and the quality of your plan depends on how diligently your senior architect goes through the plans and corrects any errors there might be.
These architectural practices also employ more members of staff, have larger offices, and more insurance, so their fees are often higher.
10.2. Online Architects
Advantage: Online architecture is a relatively new phenomenon. They often quote very low fees justified by the fact they don’t have offices. They might also work remotely, so will always be free to hop on a shared screen call to discuss your project which is very useful.
Disadvantage: In our experience, lots of these online architects charge relatively low fees initially but then there may be lots of add-ons once you instruct them, similar to when Ryan Air quote £60 for a ticket but then you might need to pay extra to pick a seat or to bring a suitcase.
They may quote a relatively low fee for an initial feasibility study but then may charge additional fees to survey your house, attend a pre-application meeting, to submit your application to planning, etc.
When receiving a quote, make sure it includes a very clear breakdown of what’s included. It’s also sometimes a good idea to ask if there could be any additional fees later down the line.
10.3. Cad Technicians or Architectural designer
Advantage: It takes nearly seven years to become an architect in the UK. However, there are a group of people who call themselves ‘architectural designers’ or ‘CAD technicians’. They carry out similar work to traditional architects. The main advantage of this group is that their fees will often be lower than traditional architects. This is because they are usually freelancers, and they might not have the same level of experience as traditional ‘architects’.
Disadvantage: This really comes down to experience and knowledge. Anyone is allowed to call themselves an architectural designer without having any experience. Although, the fee they quote might be very low. They won’t have the same level of experience as an architect which means your dream home might not be built to the same standard as a traditional architect who charges a little more.
11. How to make sure you are hiring a real architect
The Architects’ Register is the definitive record of all UK architects. If someone is not on the register, they are not an architect – it’s as simple as that.
The title “architect” is protected by law in the UK. It can only be used by people who have the appropriate education, training and experience needed to join the Architects’ Register. It’s quick and easy to check the register to confirm whether someone is a genuine architect. By checking the register before commissioning services, you can make an informed choice about who to hire for your project.
If you have received a quote and want to check if they are indeed an ‘architect’, you can check by clicking here, which will take you through to the Architect Registration Board website.
12. How to agree your architects’ fees
We would always advise contacting friends and family to see if anyone can recommend a good architect. If you’re using Google for a little help, check their reviews. Have their previous clients enjoyed working with them?
We know that when it comes to fee proposals, there is no standard template. You might receive three quotes that are all structured differently and range in price.
If that’s the case, feel free to call each architect so they can explain each stage in detail. Are there any hidden costs which might crop up after the project starts? Can they give you an estimate of other processional fees you might need to pay, such as: a structural engineer, a party wall survey, building regulations fees?
Conclusion
There are hundreds if not thousands of architects to choose from in the UK. Our approach when trying to find a good one would be:
- Contact friends or family to see if anyone can recommend a good architect they previously worked with
- Prepare a shortlist of architects to approach
- Make a list of all your design ideas
- Obtain fee proposals from your chosen architects
- Contact each one to ask any questions about their proposal
- Most importantly, choose the architect that is not only within your budget but the one who also has the most enthusiasm and creativity.
At Adara, our team of architects and planners have a huge amount of experience in designing incredible new extensions to transform your home.
If you have any ideas you would like to discuss with one of our architects, you can book a free 30 min consultation here.
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