If you already have planning drawings and are moving towards construction, one of the next costs you are likely to encounter is the Building Regulations technical design.
So how much should Building Regulation drawings actually cost?
There is no single national fee.
Published prices in 2026 range from around £600 for some straightforward drawing-only packages to £1,000–£2,000 or more for more comprehensive technical services, with higher fees possible for complicated extensions, loft conversions, multi-storey projects or packages that include structural engineering and other specialist work.
The biggest problem when comparing quotes is that the words:
“Building Regulations drawings”
do not always mean the same thing.
One quote might include only architectural technical drawings.
Another might include:
- technical drawings;
- construction details;
- written specifications;
- structural calculations;
- steel beam design;
- revisions;
- Building Control coordination; and
- submission support.
The headline price alone therefore tells you very little.
At BuildRegs, the aim is simpler: if you already have suitable planning or architectural drawings, you can upload them online, we review the actual project and provide a fixed quotation before you proceed.
Quick Answer: How Much Do Building Regulation Drawings Cost?
For a typical residential project in 2026, published market prices for Building Regulations drawing services vary significantly.
As a broad guide:
| Project / service | Typical published pricing seen in 2026 |
|---|---|
| Straightforward Building Regulation drawing package | Around £600–£1,300+ |
| Building Regulations drawings + separate structural design | Often £1,000–£2,000+ combined |
| More comprehensive extension technical packages | Around £1,500–£3,000+ |
| More complicated / bespoke projects | Individually quoted |
These are indicative market figures rather than regulated or fixed national prices. Different providers include different services.
BuildRegs currently advertises residential technical packages from approximately:
Single-storey extension — from £799Loft conversion — from £849Double-storey extension — from £999Garage conversion — from £749Structural opening / load-bearing wall calculations — from £249
with the final project price confirmed after reviewing the drawings.
What Are You Actually Paying For?
Building Regulations drawings are not simply another version of the planning plans.
They develop an architectural proposal into a much more technical design.
Depending on the project, this can involve specifying:
- foundation construction;
- external walls;
- insulation;
- ground floors;
- roof construction;
- drainage;
- ventilation;
- fire safety;
- structural openings;
- windows and glazing;
- structural steelwork;
- technical notes; and
- construction details.
The government's Approved Documents provide guidance on ways to satisfy the various requirements of the Building Regulations in England. The relevant topics include structure, fire safety, moisture, ventilation, drainage, energy efficiency, electrical safety and others.
The professional fee therefore reflects the work involved in converting a basic design into a coordinated technical package.
Building Regulation Drawings Cost vs Planning Drawings Cost
It is important not to compare the two as though they are interchangeable.
Planning drawings
Planning drawings are primarily concerned with:
- proposed size;
- appearance;
- position;
- massing;
- windows;
- doors;
- roof form; and
- relationship to neighbouring properties.
Building Regulation drawings
Building Regulation drawings answer much more detailed questions, such as:
- What supports the extension?
- What insulation is being used?
- How is the wall constructed?
- What steel supports the existing house?
- How is the roof built?
- Where does the drainage go?
- How is the floor damp-proofed?
- How is fire safety addressed?
Planning permission and Building Regulations approval are separate processes. GOV.UK confirms that the Building Regulations 2010 cover the construction and extension of buildings and that Building Regulations approval may be required even where planning permission has already been dealt with.
What Does the Market Charge for Building Regulation Drawings in 2026?
There is a considerable difference between providers.
Current published examples illustrate the range.
AC Design Solution
Its August 2026 pricing page advertises Building Regulation drawing packages from:
- £600 for a single-storey extension;
- £600 for a loft conversion; and
- £1,300 for a double-storey extension.
It explicitly states these are its own starting prices rather than national averages.
Draw & Plan
Its current Building Regulations drawing service starts at:
£950 + VAT
with structural design charged separately. Its published structural-engineering prices start from £395 for a simple single-storey extension.
That means a basic extension could start around:
£950 + VAT for drawings
plus
£395 for structural design
before other relevant fees.
Horizon Architecture
Current published fees show:
Building Regulations package — from £1,295
with specialist consultants, statutory fees and VAT where applicable charged separately.
The Extension Company
Its current 2026 guide gives a much wider indicative range of approximately:
£1,500–£3,000
for Building Regulation drawings including construction detail, specifications and structural calculations.
This variation demonstrates why searching only for the lowest headline fee can be misleading.
Why Are Some Building Regs Drawings £600 and Others £2,000+?
Usually because you are not comparing identical services.
Consider these two quotes:
Quote A — £650
Includes:
- technical architectural drawings.
Structural engineering is extra.
Building Control fee is extra.
Survey may be extra.
Revisions may be limited.
Quote B — £1,400
Includes:
- Building Regulation drawings;
- construction specifications;
- structural calculations;
- steel beam design;
- structural coordination;
- revisions; and
- Building Control support.
At first glance, Quote A appears half the price.
Once the missing services are added, the total may be much closer.
The correct question is therefore not simply:
“How much are the drawings?”
It is:
“What will I need to spend to obtain the complete technical package required for my particular project?”
What Affects the Cost of Building Regulation Drawings?
Several factors influence the fee.
1. Type of Project
A garage conversion is usually different in complexity from a double-storey extension.
A straightforward rear extension may be relatively standard.
A loft conversion can involve:
- new floors;
- multiple steel beams;
- dormer structure;
- stair design;
- fire strategy;
- roof alterations; and
- insulation.
A new-build house is substantially more involved again.
2. Project Size
A larger project normally contains more construction information.
For example, a double-storey extension can require:
- additional plans;
- additional sections;
- first-floor structure;
- more structural design;
- roof design;
- fire-safety consideration;
- additional windows and doors; and
- more complex load paths.
That is why a double-storey extension would ordinarily cost more to design technically than a very small single-storey addition.
3. Structural Complexity
This can make a particularly large difference.
Compare:
Extension A
A simple rear extension connected through the existing doorway.
Extension B
A rear extension where the homeowner wants almost the entire back wall of the house removed, plus 5-metre sliding doors and a roof lantern.
Extension B may require:
- main structural beam;
- additional beam over glazing;
- columns;
- goalpost frame;
- padstones;
- rooflight trimming; and
- more substantial calculations.
Both may have similar floor areas.
But technically they are very different projects.
4. Structural Calculations
One of the biggest pricing differences is whether structural calculations are included.
Common calculations can include:
- steel beams;
- load-bearing wall removals;
- columns;
- padstones;
- roof beams;
- floor joists;
- loft floor structures;
- dormer structures; and
- foundations.
Some architectural practices provide only the Building Regulations drawing package and ask the client to appoint a separate structural engineer.
For example, one current London provider advertises Building Regulations drawings from £950 + VAT, with structural design for a simple extension starting at an additional £395.
When comparing prices, always check this.
5. Quality of the Drawings You Already Have
If you already possess a good set of:
- measured survey drawings;
- existing plans;
- proposed plans;
- elevations;
- sections; and
- planning drawings,
the Building Regulations designer can often use those as the basis of the technical design.
This can make a remote technical service significantly more efficient.
If there are no usable existing drawings, additional survey or drawing work may be necessary.
That is part of the reason BuildRegs is particularly suited to homeowners who have already completed the planning/design stage and now need the technical stage.
6. Whether a Measured Survey Is Required
Some practices build a site survey into their fees.
Others assume you already have drawings.
For example, current London competitors advertise measured surveys separately or include them only in broader planning packages.
If you already have accurate architectural drawings, paying for another full measured survey may sometimes duplicate information you already possess.
Where further dimensions or site information are needed, those should instead be identified from the project.
7. Roof Complexity
A simple flat roof will usually involve less structural design than a complex roof containing:
- multiple valleys;
- large roof lantern;
- large rooflights;
- vaulted ceilings;
- unusually long spans;
- complicated intersections; or
- several structural beams.
Roof complexity can therefore affect both the drawing and structural-engineering fee.
8. Drainage
Drainage can be straightforward or surprisingly involved.
Cost and design complexity can increase where:
- drains run through the proposed extension;
- inspection chambers require alteration;
- public sewers are affected;
- new bathrooms are proposed;
- drainage layouts are unclear; or
- surface-water disposal requires a new solution.
9. Fire-Safety Complexity
Fire design becomes increasingly important for projects such as:
- loft conversions;
- houses converted into flats;
- extensive open-plan alterations;
- multi-storey extensions; and
- changes of use.
A conventional rear extension is not necessarily comparable with a project requiring a more complicated fire strategy.
10. Number of Design Revisions
If the planning design is settled, producing the technical package is normally more efficient.
If the client continues changing:
- door positions;
- room layouts;
- roof type;
- structural openings;
- glazing;
- extension size;
after structural design has started, drawings and calculations may need revising.
This can affect fees.
What Is Included in the Quote?
Different providers include different things. This comparison shows what is typically covered.
| What the quote includes | Budget drawing service | BuildRegs-style coordinated service | Broader architectural practice |
|---|---|---|---|
| Existing planning drawings used | Often | Yes | Sometimes |
| Building Regs drawings | Yes | Yes | Yes |
| Structural calculations | Often extra | Where required in package | Often separate |
| Fixed quote | Varies | Yes | Varies |
| Online service | Often | Yes | Varies |
| Building Control fee | Extra | Extra | Extra |
| Full planning service | Usually no | Not required if already completed | Often available |
How Much Do Building Regulation Drawings Cost for a Single-Storey Extension?
Current market examples suggest that drawing-only packages can start around £600–£1,300, although more comprehensive architectural and structural packages can cost considerably more.
BuildRegs currently advertises:
Single-storey extension packages from £799
for technical drawings and structural calculations for suitable residential extension projects, with the final fee confirmed after the plans are reviewed.
A more complex extension may cost more.
Relevant factors include:
- size;
- number of beams;
- structural openings;
- roof design;
- drainage;
- existing information; and
- overall technical complexity.
How Much Do Building Regulation Drawings Cost for a Loft Conversion?
Loft conversions can require a substantial amount of technical information.
A package may need to cover:
- new loft floor;
- steel beams;
- roof alterations;
- dormer;
- rooflights;
- staircase;
- fire protection;
- insulation;
- ventilation;
- drainage; and
- structural calculations.
Published competitors currently advertise Building Regulations-only loft drawing services around the £600–£950+ range at the lower end, while all-in architectural packages can be considerably higher.
BuildRegs currently advertises:
Loft conversion technical packages from £849.
Again, the final quote depends on the proposed structure and the drawings available.
How Much Do Building Regulation Drawings Cost for a Double-Storey Extension?
Double-storey extensions tend to require more design work.
Current competitor starting prices vary considerably. One current provider advertises a double-storey Building Regulation drawing package from £1,300, while broader market packages can run materially higher.
BuildRegs currently advertises:
Double-storey extension packages from £999.
More complicated structural arrangements would be assessed individually.
How Much Do Building Regs Drawings Cost for a Garage Conversion?
Garage conversions can sometimes involve fewer structural changes than an extension, although technical design is still required.
The drawings may address:
- insulated floor;
- external walls;
- infill to garage door opening;
- windows;
- ventilation;
- fire protection;
- damp;
- roof/ceiling insulation;
- drainage; and
- structural alterations.
BuildRegs currently advertises:
Garage conversion packages from £749.
What About a Load-Bearing Wall?
If you are not extending the house and simply need to remove a structural wall, you may not require a full extension drawing package.
The principal requirement might instead be:
- existing/proposed structural arrangement;
- steel beam calculation;
- beam reactions;
- bearings;
- padstones; and
- appropriate supporting information.
BuildRegs currently advertises structural-opening calculations from:
£249.
This is why pricing should match the project rather than force every homeowner into one package.
Does the Price Include Structural Calculations?
This is one of the most important questions to ask.
Never assume that:
“Building Regulations package”
automatically means:
“Building Regulations drawings + structural calculations.”
Many firms charge separately.
One current provider, for example, advertises drawings from £950 + VAT and structural design from a further £395 for a straightforward single-storey extension.
Before accepting a quote, establish whether it includes:
- beam calculations;
- column calculations;
- padstone design;
- roof calculations;
- structural plans;
- engineering revisions; and
- coordination with the drawings.
BuildRegs' commercial proposition should make this distinction especially clear.
Does the Price Include the Building Control Fee?
Usually not.
This is a separate cost.
The professional fee paid to prepare the drawings is not the same as the fee charged by the Building Control body.
GOV.UK states that local authority Building Control charges depend on matters such as:
- type of work;
- inspections;
- number of dwellings; and
- floor area for work such as extensions.
Private registered building control approvers negotiate their own fees.
So your overall budget might contain:
Building Regulation drawings
Structural calculations
Building Control application/inspection fee
potentially other specialist costs.
How Much Does Building Control Cost?
There is no single national Building Control fee.
Local authorities set charges based on their costs, while registered building control approvers negotiate commercial fees. GOV.UK specifically says the price can depend on the type of work, site inspections, number of dwellings and total floor area.
Your designer's £799 or £1,200 fee should therefore not be confused with the Building Control charge itself.
This distinction should always be shown clearly in quotations.
What About Planning Fees?
Planning is another separate process.
If planning permission has already been obtained, there is no reason to include a new planning package within a Building Regulations-only quotation unless further planning work is genuinely required.
This is where homeowners who already have approved plans can potentially save money.
Instead of buying:
survey + planning drawings + planning submission + technical drawings
again,
you may simply require:
Building Regulation drawings + structural calculations.
Do I Have to Use the Architect Who Prepared My Planning Drawings?
No.
There is generally no requirement to return to the same architectural practice for the Building Regulations stage.
If you have suitable existing drawings, another competent designer can potentially develop the technical package.
That can be useful if:
- your original architect does not provide Building Regulations services;
- structural calculations are excluded;
- their technical-stage fee is high;
- there is a long waiting period; or
- you want a more streamlined online service.
You should ensure you have the necessary right to use/share the drawings for the purpose intended.
Can Building Regulation Drawings Be Prepared Online?
For many straightforward residential projects, yes.
If accurate architectural drawings already exist, much of the technical-design work can be completed remotely.
Useful information may include:
- plans;
- elevations;
- sections;
- planning drawings;
- dimensions;
- property photographs;
- drainage information; and
- information about existing construction.
Where something cannot reliably be established from the available information, further measurements, photographs, opening-up or site investigation may still be necessary.
An online service works best when it uses remote delivery efficiently without pretending that every property can be designed from insufficient information.
Are Cheap Building Regulation Drawings a False Economy?
Not necessarily.
A lower fee does not automatically mean poor work.
Online working, standardised processes and lower overheads can genuinely reduce the cost of technical design.
But an unusually cheap quote deserves closer inspection if important services are missing.
Before comparing fees, ask:
Are structural calculations included?
Are technical construction sections included?
Are detailed specifications included?
Are revisions included?
Does the package correspond with the structural design?
What happens if Building Control has a technical query?
Is the Building Control fee separate?
A £600 quotation that becomes £1,500 once everything necessary is added is not really a £600 service.
Is an Expensive Architect Automatically Better?
Not necessarily either.
Traditional architectural practices often offer services far beyond the Building Regulations stage.
Their fee may reflect:
- measured survey;
- conceptual design;
- planning strategy;
- planning application;
- design revisions;
- technical design;
- tendering;
- contractor selection;
- contract administration;
- site inspections; and
- construction-stage management.
That may be entirely appropriate for a complex project.
But if you have already paid for planning drawings and simply need the technical Building Regulations stage, you may not need that entire service again.
This is where a specialist Building Regulations service can make economic sense.
What Should Be Included in a Good Building Regulation Drawing Package?
The precise content depends on the project, but a residential package may include:
- proposed floor plans;
- elevations;
- sections;
- foundation details;
- ground-floor construction;
- external wall construction;
- roof construction;
- insulation;
- damp protection;
- drainage;
- ventilation;
- fire-safety details;
- structural member positions;
- technical specifications; and
- structural calculations where included.
The key is not the number of sheets.
It is whether the package adequately describes the proposed technical design.
Should Structural Calculations Be Bought Separately?
Sometimes there is good reason to use a separate structural engineer.
But if your project needs both architectural technical drawings and engineering, a coordinated service can reduce administrative work.
Consider the traditional route:
Architectural designer
↓
technical drawings
↓
Structural engineer
↓
beam/calculations
↓
architect updates drawings
↓
engineer changes beam
↓
drawings updated again.
A coordinated service aims instead for:
Existing architectural drawings
↓
Technical design
Structural design
↓
one coordinated package.
For straightforward residential projects, that can be a significant practical benefit.
Example: Comparing Two Extension Quotes
Imagine a homeowner has planning permission for a single-storey rear extension.
They receive two quotes.
Provider A
£650
Includes:
- Building Regulations drawings.
Does not include:
- structural calculations;
- steel-beam design;
- Building Control fee.
Structural engineering later costs another £550.
Total professional design cost: £1,200
before Building Control charges.
Provider B
£850
Includes:
- Building Regulations drawings;
- relevant structural calculations;
- coordinated technical package.
The £850 quote was apparently more expensive.
But the complete cost was lower.
This is why the scope needs to be compared, not just the headline figure.
Example: Loft Conversion Costs
The same issue occurs with loft conversions.
A £700 drawing service may sound attractive.
But subsequently you discover that you also need:
- structural engineer — £600;
- revisions — extra;
- fire strategy adjustment — extra;
- Building Control fee — separate.
Another £900–£1,200 technical package might include substantially more from the beginning.
Again, compare the completed scope.
Why BuildRegs Uses Fixed Quotes
Residential projects are similar enough to standardise the process but different enough that one price cannot accurately cover every situation.
A fair model is therefore:
Starting price
gives the homeowner an idea of likely cost.
Then:
Plans are reviewed
to understand the actual scope.
Then:
Fixed price is confirmed
before technical work begins.
This avoids hourly billing uncertainty while preventing a simple project from subsidising a very complex one.
What Can Make My BuildRegs Quote Higher Than the Starting Price?
A more complicated project could involve:
- several structural beams;
- structural columns;
- goalpost or box frames;
- unusual foundations;
- complex roof geometry;
- major structural alterations;
- significant missing information;
- multiple building types;
- unusual fire requirements;
- complex drainage;
- extensive technical revisions; or
- other specialist design work.
The important point is that any adjustment should be established before you proceed, not discovered unexpectedly after the project has started.
How Can I Keep Building Regulation Drawing Costs Down?
The easiest way is to provide good information from the start.
If available, send:
- approved planning drawings;
- DWG files;
- PDFs;
- plans;
- elevations;
- sections;
- site photographs;
- structural information already prepared;
- drainage information; and
- Building Control correspondence.
Also try to settle major design decisions before the structural work is completed.
Changing a window is one thing.
Changing a 3-metre opening into a 6-metre structural opening after the beam has been calculated is another.
Should I Pay for Building Regulation Drawings Before Planning Permission?
It depends on the project.
For work where planning permission is uncertain, completing the full technical design before the planning issue is resolved may expose you to unnecessary redesign costs.
A common sequence is:
Planning / permitted development position confirmed
↓
Design settled
↓
Building Regulations technical package
↓
Building Control process
↓
Construction
Where the planning position is already established, there is much less reason to delay the technical stage.
How Long Do Building Regulation Drawings Take?
Timescales depend on complexity and the information available.
Some providers advertise technical-drawing turnarounds of around seven days for suitable residential projects, while more complex work can take longer.
The design timescale is separate from Building Control review.
For Full Plans applications in England, GOV.UK currently states that a decision is normally expected within five weeks, or two months with the applicant's consent.
BuildRegs' project-specific quotation should state the anticipated drawing/calculation turnaround separately.
Full Plans or Building Notice?
For ordinary work that is not part of the higher-risk building regime, GOV.UK currently describes Full Plans as the most thorough route.
Under Full Plans, technical information is submitted for assessment and a formal decision is provided.
A Building Notice is available only for smaller projects and does not result in the same formal approval of the plans.
Where an extension or loft conversion contains significant structural and technical design, preparing the technical package before construction can provide much greater clarity regardless of the Building Control route.
Are Building Regulation Drawings Worth Paying For?
For a project costing tens of thousands of pounds to construct, good technical information can represent a relatively small proportion of the overall budget.
Its value lies in resolving questions before they become site problems.
Without sufficient technical design, a builder can be left asking:
- What size steel?
- What insulation?
- What foundations?
- What roof joists?
- How do we build the wall?
- Where does the drain go?
- What fire protection is needed?
Resolving these during design is usually preferable to solving them reactively while labour and materials are already waiting on site.
What Should I Check Before Accepting a Quote?
Before comparing Building Regulation drawing fees, establish:
- Are structural calculations included?
- Are steel beam calculations included where required?
- Are plans, sections and construction details included?
- Does the price include technical specifications?
- Are reasonable technical revisions included?
- Is the Building Control fee separate?
- Is Building Control submission included or excluded?
- Is a measured survey required?
- Does VAT apply?
- What is the expected turnaround?
- What happens if additional site information is needed?
- What happens if Building Control raises a technical query?
Two quotes should only be compared after answering those questions.
How Much Could My Project Cost With BuildRegs?
BuildRegs currently publishes starting prices including:
Single-storey extension
From £799
Double-storey extension
From £999
Loft conversion
From £849
Garage conversion
From £749
Load-bearing wall / structural opening
From £249
Outbuilding and new-build projects
From £749–£1,499
The actual fee is confirmed after reviewing the project rather than relying solely on the starting price.
This makes it possible to price the work around the real technical requirement.
I Already Have Planning Drawings — Can I Get a Quote?
Yes.
In fact, this is the ideal starting point.
If you already have:
- approved planning drawings;
- permitted-development drawings;
- existing and proposed plans;
- architectural drawings; or
- another suitable design package,
upload them for review.
BuildRegs can assess what is likely to be needed for the technical Building Regulations stage and provide a fixed quotation.
You do not need to determine the required steel beams, insulation or structural calculations yourself beforehand.
Frequently Asked Questions
Published 2026 prices vary widely. Straightforward drawing packages can begin at around £600–£1,300, while more comprehensive technical and structural packages can cost £1,500–£3,000 or more depending on the project and what is included.
Because providers offer different scopes. Some prices cover technical drawings only, while others include structural engineering, surveys, specifications, revisions or submission support.
Sometimes, but not always. Always check the quotation. Some practices charge separately for structural calculations.
Current published market prices for drawing-only services can begin around £600–£1,300, with broader packages costing more. BuildRegs currently advertises single-storey extension technical packages from £799, subject to project review.
Prices vary according to loft type and structural complexity. BuildRegs currently advertises loft-conversion technical packages from £849.
Usually it is a separate statutory/commercial charge. Local authority fees depend on factors including project type, inspections and floor area, while registered building control approvers set their own commercial fees.
Not necessarily. Building Regulations drawings are a separate stage. If you already have planning drawings, they can often be used as the starting point for the technical work.
Yes. You do not generally need to use the same practice that prepared the planning drawings, provided the necessary project information and rights to use the drawings are available.
Many conventional residential projects can be developed remotely where suitable drawings, dimensions and photographs are available. Additional site information may still be required where conditions cannot be established reliably.
Price alone does not determine quality. The important issue is whether the scope is appropriate, technically competent and sufficiently coordinated for the project.
There is no need to guess what your project should cost.
If you already have planning or architectural drawings, send them to BuildRegs.
We can review the proposed work and confirm the scope for:
Building Regulation drawings
and
Structural calculations where required.
You then receive a fixed quotation before deciding whether to proceed.
Current guide prices start from £249 for structural openings and from £749 for complete residential technical packages.
