How Much Does an Architectural Designer Cost in Cambridgeshire?
If you're considering extending, renovating or altering your home, one of the first questions you're likely to ask is “How much will an architectural designer cost?”
There are a number of different costs to consider when planning a building project, including architectural design, planning permission, Building Regulations, structural engineering and, of course, the construction itself.
The cost of architectural services can vary considerably depending on the size and complexity of your project. A small porch extension is very different from a large two-storey extension or a new-build house, so there isn't one standard price that applies to every project.
At Holmes Architecture & Planning, we believe in being transparent about our fees from the outset. Rather than offering a standard package price for every project, we review each enquiry individually, establish what is required and provide a fixed-fee quotation before any work begins.
In this guide, we'll explain the different costs you may need to consider when planning a project in Cambridgeshire and what you can expect to receive for your money.
How much does an architect charge?
Architectural designers and architects can charge for their services in several different ways.
Some practices charge an hourly rate, some charge a percentage of the overall construction cost, while others provide a fixed fee for a defined scope of work.
For residential projects, fixed fees can provide homeowners with greater certainty, as you know what you're going to pay for the agreed scope of work before the project begins.
As a general UK comparison, published 2026 cost guides show that architectural design fees can vary significantly depending on the service being provided, with fixed fees commonly used for residential extensions and percentage-based fees also used for larger or more comprehensive projects.
At Holmes Architecture & Planning, we generally work on a fixed-fee basis.
Our typical planning drawing packages currently range from approximately:
£495 for smaller projects, such as porch extensions
£1,895 for larger two-storey extensions
£2,495 for new-build planning drawing packages
These are examples rather than standard prices, as every project is different.
Our fees include detailed drawing packages, specifications and 3D visuals, with additional services such as photorealistic 3D models and animations available where required.
The important thing to remember is that the cheapest quote isn't necessarily the best value. You should always establish exactly what is included in the fee, how many revisions are allowed, whether planning amendments are included and what happens if the scope of the project changes.
How much are architectural drawings?
The cost of architectural drawings depends on what you're trying to achieve and how much information is required.
A basic planning drawing package for a small extension is naturally going to cost less than a comprehensive drawing package for a large two-storey extension or new-build property.
Planning drawings may include:
Existing floor plans
Proposed floor plans
Existing elevations
Proposed elevations
Site location plans
Block plans
Roof plans
Sections
Proposed materials
Design information
Specifications
Design and Access Statements
Heritage Statements
3D visuals
The exact requirements will depend on the project and the type of application being made.
At Holmes Architecture & Planning, our planning drawing packages typically range from around £495 to £2,495+, depending on the size and complexity of the project.
We don't have an off-the-shelf price because we don't believe that every extension or house should be treated in exactly the same way.
Instead, we review the property and your requirements and provide a fixed quotation based on the actual work involved.
How much does planning permission cost?
There are actually two separate costs to consider when talking about planning permission:
The planning application fee paid to the Local Planning Authority.
The professional fees for preparing and submitting the application.
For a standard householder planning application in England, the current planning application fee is £548 from 1 April 2026. Certain other types of applications have different fees; for example, a larger rear extension requiring prior approval under Permitted Development currently has a fee of £249.
Please see chart below for current application fees (as of August 2026)
Application type & Current Fee
Householder application – extension, alteration or improvement to an existing house
£548
Householder application – ancillary works such as certain outbuildings, fences, walls etc.
£272
Prior Approval – larger rear extension
£249
Full planning application – 1 new dwelling
£610
Full planning application – 2 to 50 new dwellings
£610 per dwelling
Full planning application – 51+ dwellings
£31,185 + £189 per dwelling over 50
Outline application – residential development under 0.5 ha
£610 per 0.1 ha (or part thereof)
Outline application – 0.5–2.5 ha
£659 per 0.1 ha (or part thereof)
Permission in Principle
£531 per 0.1 ha (or part thereof)
The planning application fee is separate from your architectural designer's fee.
You will therefore need to budget for the drawings and design work required to prepare the application, as well as the application fee itself.
Depending on the project, there may also be additional costs for things such as:
Measured surveys
Structural engineers
Heritage statements
Arboricultural reports
Ecological surveys
Drainage information
Other specialist reports
Not every project will require these.
At Holmes Architecture & Planning, we discuss the requirements of your project at the beginning and provide a clear quotation so you understand what is included.
How much do Building Regulations drawings cost?
Building Regulations drawings are more detailed than planning drawings and are concerned with how the building will actually be constructed, rather than simply whether the proposed development is acceptable from a planning perspective.
A Building Regulations package can include detailed information relating to:
Construction build-ups
Foundations
Insulation
Floors
Roof construction
Walls
Doors and windows
Fire safety
Ventilation
Drainage
Structural elements
Thermal performance
Other relevant technical requirements
The cost will depend on the size and complexity of the project and how much technical information is required.
For example, a straightforward single-storey extension may require significantly less work than a large two-storey extension involving substantial structural alterations and changes to the existing property.
Our Building Regulations drawing packages are typically priced at a similar level to our planning drawing packages. For example, a larger two-storey extension may be around £1,895 for the planning stage, with a further £1,895 for the detailed Building Regulations stage.
These figures are provided as a guide only, as the final fee will depend on the size, complexity and specific requirements of each project. We review every project individually and provide a clear, fixed-fee quotation based on the work involved.
It's also important to check whether your quotation includes Building Regulations drawings or only planning drawings. A low initial quote can sometimes appear attractive but may not include everything you'll need to actually build the project.
How much does a structural engineer cost?
The cost of a structural engineer varies depending on the work required.
For a straightforward residential project, structural engineering may involve calculations for things such as steel beams and foundations. More complex projects can require considerably more structural design.
Current 2026 UK cost guides suggest that straightforward structural engineering work can start from several hundred pounds, while structural design for a larger extension can commonly run into the £1,000–£3,000+ range, depending on complexity and what's included.
For example, you may need a structural engineer to calculate:
Steel beams
Foundations
Roof structures
Load-bearing walls
Structural openings
Floor structures
Structural alterations
More complex foundation solutions
The structural engineer's fee is separate from the architectural designer's fee unless specifically stated otherwise.
At Holmes Architecture & Planning, we can advise you where structural engineering is likely to be required and coordinate with a structural engineer as part of the design process.
What affects an architect's fee?
There are many factors that can influence the cost of architectural services.
The size of the project
A small porch extension will require considerably less design work than a large two-storey extension or new-build house.
The complexity of the design
A straightforward rectangular extension is generally simpler to design than a project involving complicated roof structures, multiple extensions or significant alterations to an existing building.
The existing property
Older or unusual properties can require additional investigation and design work. Listed buildings and properties within Conservation Areas may also require additional consideration.
Planning requirements
Some projects are relatively straightforward from a planning perspective, while others may require more detailed justification, consultation or supporting information.
The level of service you require
There is a significant difference between:
Planning drawings only
and:
Planning + Building Regulations drawings
and:
Full architectural services through to construction.
It's therefore important to compare quotations based on what is actually included, rather than simply comparing the headline price.
Revisions
The amount of design development and revisions required can also affect the amount of work involved.
At Holmes Architecture & Planning, we allow for a reasonable number of revisions within our fee proposals, giving our clients flexibility to develop the design without worrying about every minor change creating an additional charge.
Changes requested by the planning authority
We also allow for reasonable amendments requested by the Local Planning Authority during the application process within our agreed fee.
This means our clients have greater certainty about the cost of the planning stage.
Are Architectural Designer fees worth it?
For many homeowners, one of the biggest benefits of using an architectural designer is having someone who can identify what's possible and develop the right solution before you commit to construction.
A good design can help you make better use of the available space, improve the relationship between the existing house and the extension, deal with planning constraints and provide your builder with the information they need.
There can also be considerable value in having someone experienced in planning applications manage the process.
A poorly considered design can potentially lead to delays, redesign work or a planning refusal. Getting professional advice early can help identify potential problems before they become expensive.
However, it's important to choose the right service for your project.
Not every homeowner needs a full architectural service from initial concept through to completion. For some projects, a planning drawing package may be all that's required. For others, detailed Building Regulations drawings and construction support may be appropriate.
At Holmes Architecture & Planning, we discuss the project with you at the beginning to establish what you actually need, rather than automatically providing services that aren't necessary.
How much does an extension cost overall?
Architectural fees are only one part of the overall cost of an extension.
The total cost will depend on the size, specification and complexity of the project.
You may need to budget for:
Cost
What it covers
Architectural designer - Design, drawings and planning
Planning application - Local Authority application fee
Measured survey - Survey of the existing property
Structural engineer - Structural calculations and design
Building Regulations - Technical drawings/approval
Construction - Builder, labour and materials
Kitchen - If included within the project
Bathroom - If included within the project
Windows & doors - New openings and external elements
Heating/electrical - Alterations and new installations
Drainage - New or altered drainage
Specialist reports - Where required
As a result, the cost of an extension can't realistically be calculated simply by multiplying its floor area by a single figure.
The specification makes a significant difference.
A simple extension with standard finishes will have a very different cost to a high-specification extension with large areas of glazing, bespoke joinery, a new kitchen, underfloor heating and extensive internal alterations.
This is why we recommend establishing your overall budget at the beginning of the design process.
Your architectural designer should understand your budget and design the project accordingly.
Watch out for our future Blog posts where we will revisit some of our previous projects and break down the costs involved.
What does Holmes Architecture & Planning include?
At Holmes Architecture & Planning, we believe the process should be straightforward, transparent and tailored to each individual project.
We don't offer an off-the-shelf price because every property and every client's requirements are different.
Instead, we review each enquiry individually, discuss what you're looking to achieve and establish the work involved.
We then provide a fixed-fee quotation upfront, so you know what you're paying for before the work begins.
Our typical planning drawing packages range from approximately:
£495 Smaller projects, such as porch extensions
£1,895 Larger two-storey extension planning packages
£2,495 New-build planning drawing packages
These figures are intended as a guide rather than fixed prices, and your quotation will depend on the specific requirements of your project.
Our planning drawing packages can include:
Detailed architectural drawings
Planning documentation
Specifications
3D visuals
Design revisions
Planning application preparation and submission
Where required, we can also provide additional services such as photorealistic 3D models and animations.
We also allow for a reasonable number of revisions within our fee proposals, and reasonable amendments requested by the Local Planning Authority during the planning process are covered within our agreed fee.
Most importantly, our agreed fee doesn't suddenly increase unless the brief or scope of work changes.
We believe this gives our clients peace of mind and allows them to move forward with their project knowing exactly what our services will cost.
Planning an extension or alteration to your home?
If you're considering extending, renovating or altering your property, we'd be happy to discuss your ideas and advise you on the potential options.
Whether you're considering a single-storey extension, two-storey extension, loft conversion, new build or another type of residential project, we can help you understand what's involved and what the next steps are.
Get in touch with Holmes Architecture & Planning to discuss your project and receive a clear, fixed-fee quotation.
