Mechanical · Electrical · Plumbing
MEP & Building Services Design
Coordinated mechanical, electrical and plumbing design for residential and small commercial projects — heating and ventilation, power and lighting, and water and drainage, designed together so the systems fit the building and meet the Building Regulations. One coordinated package your whole team can price and build from.
What is MEP?
The systems that make a home work — designed together
MEP — mechanical, electrical and plumbing — is everything behind the finishes: heating, ventilation and hot water; power, lighting and distribution; and water supply and drainage. Designed in isolation, these services clash, underperform and overrun. Designed together, and against the architecture and structure, they fit the building, run efficiently and sail through building control.
Crown prepares MEP and building-services design under the same roof as the architecture and structural engineering, which is exactly why our services coordinate properly rather than fighting for the same ceiling voids, risers and chases. Every radiator, socket, light, pipe and drain is placed deliberately, sized correctly and shown clearly, so your builder, heating engineer, electrician and plumber all work from one consistent, buildable package.
We work across London and the South East on extensions, loft and garage conversions, basements, full refurbishments and new builds, as well as light commercial projects. Whatever the scale, the principle is the same: resolve the services on the drawing board — where changes are free — rather than on site, where they are slow and expensive. That is what keeps a project on programme, on budget and genuinely efficient to run for decades.
MEP services
Building-services design and drawings
Each service is coordinated with your architectural layout and prepared for building control and your installers, across London and the South East.
MEP Design
Coordinated mechanical, electrical and plumbing design for residential and small commercial projects — heating and ventilation, power and lighting, and water and drainage, designed together so the systems fit the building and meet the Building Regulations.
Explore MEP design →M&E Drawings
Mechanical and electrical drawings for extensions, conversions, refurbishments and new builds — clear, buildable layouts of heating, ventilation, power, lighting and water services for pricing, building control and installation.
Explore M&E drawings →Building Services Design
Whole-building services design — heating, ventilation, hot water, electrical and drainage — sized and coordinated for comfort, efficiency and Building Regulations compliance on extensions, conversions and new homes.
Explore building services design →Electrical Design
Electrical design and drawings for domestic and small commercial projects — power, lighting, circuits and distribution laid out clearly and designed to support Part P compliance and a clean installation.
Explore electrical design and drawings →Plumbing & Drainage
Plumbing, hot/cold water and above- and below-ground drainage drawings for extensions, bathrooms, kitchens and new builds — designed to meet Part G and Part H and to give your plumber and groundworker clear, buildable information.
Explore plumbing and drainage drawings →The three disciplines
Mechanical, electrical, plumbing — one coordinated package
We design all three disciplines together so they share space sensibly and meet the relevant Building Regulations.
Mechanical
Heat-loss assessment and system sizing, heating (boilers, underfloor and heat pumps), ventilation to Part F including MVHR, and the controls strategy that keeps it all efficient.
- •Room-by-room heat loss
- •Heating & heat-pump design
- •Ventilation & MVHR
- •Controls & zoning
Electrical
Load assessment, power and lighting layouts, distribution boards and circuits, Part P support, and provision for EV charging, solar PV and battery storage.
- •Load & supply assessment
- •Power & lighting
- •Distribution & protection
- •EV, solar & data
Plumbing & Drainage
Hot and cold water, unvented cylinders and pressure, above- and below-ground drainage to Part H, rainwater and surface water, and Part G water efficiency.
- •Hot & cold water
- •Above-ground drainage
- •Below-ground & connections
- •Rainwater & SuDS
Why coordinate MEP
Fewer clashes, lower running costs, a smoother sign-off
Coordinated services design is the single biggest factor in avoiding the expensive variations that derail extensions and conversions.
What good MEP design delivers
- •Correctly sized heating, hot water and ventilation — no cold rooms, no wasted energy
- •Services routed around the structure, with space for ducts, pipes and cables
- •Electrical supply and board checked against real demand, including heat pumps and EV charging
- •Drainage with proper falls, designed before the slab goes down
- •A clear, costable package for every trade and the information building control wants
What it prevents
- •Drainage discovered to be unworkable after the groundworks are done
- •A consumer unit or supply that cannot take the new load
- •A heat pump that underperforms because the emitters were never resized
- •Ducts and pipes fighting beams in the ceiling on site
- •Three disconnected sets of drawings that no one can build from cleanly
Building Regulations
Compliance designed in from the start
We build the relevant Parts into the design throughout, so building control sign-off is straightforward rather than a series of late surprises.
Part L
Conservation of fuel and power — efficient heating, controls and the inputs that make SAP targets achievable.
Part P
Electrical safety in dwellings — a clear basis for your electrician to install, test and certify.
Part F
Ventilation — background, extract or MVHR sized to keep the home healthy and condensation-free.
Part G
Water efficiency and hot-water safety — efficient fittings and safe, correctly designed hot-water systems.
Part H
Drainage and waste — above- and below-ground drainage with proper falls and connections.
Parts B, E & M
Fire-stopping of service penetrations, acoustic separation, and accessible switch and control heights.
How it works
From your drawings to a coordinated package
Send your drawings
Share your architectural floor plans, any structural information and your priorities — comfort, running costs, special requirements and budget.
We agree the strategy
We confirm the heating, ventilation, electrical, water and drainage strategy for your project, and give you a clear, fixed fee before any work begins.
Coordinated design
We produce coordinated MEP drawings, equipment schedules and Building Regulations compliance notes — all checked against the architecture and structure.
Pricing & build
Your builder, heating engineer, electrician and plumber price and install from one consistent package, and building control has what it needs to sign off.
Areas covered
MEP design across London & the South East
We produce town and postcode-level pages so you can go straight to your area. Choose a service above, then your location or postcode district.
Counties & areas
Kent, Essex, Surrey, Hertfordshire, Berkshire, Buckinghamshire, Oxfordshire, Bedfordshire, London.
Postcode regions
London, Kent, Essex, Surrey, Hertfordshire, Berkshire, Buckinghamshire — covering 218 postcode districts.
FAQs
MEP & building services — common questions
What is MEP design?
MEP stands for Mechanical, Electrical and Plumbing — the building services that make a home work: heating, ventilation and hot water (mechanical), power, lighting and distribution (electrical), and water supply and drainage (plumbing). MEP design sizes and coordinates these systems against the architecture and structure so they fit the building and meet the Building Regulations.
Do I need MEP drawings for a home extension?
For most extensions, conversions and new builds, coordinated mechanical, electrical and plumbing information makes building control sign-off and contractor pricing far easier and prevents clashes on site. Simpler projects may only need part of the scope, and we scope the work to what your project actually requires.
How is MEP design different from architectural drawings?
Architectural drawings show the layout, form and appearance of the building; MEP design adds the heating, ventilation, electrics, water and drainage. The two should be coordinated together — which is how we prepare them, under one roof with the architecture and structure.
Will the design meet Building Regulations?
Yes. It is prepared with the relevant Parts in mind throughout: Part L (energy), Part P (electrical safety), Part F (ventilation), Part G (water efficiency and hot-water safety) and Part H (drainage), so it supports building control approval.
Can you design for heat pumps, EV charging and solar?
Yes. We assess whether the property suits a heat pump, carry out the heat-loss work and size low-temperature emitters, and we design in electrical capacity and routes for EV charging, solar PV and battery storage — even where they are installed later — so the home is genuinely ready.
Which areas do you cover?
We provide MEP and building-services design across London and the South East — every borough and surrounding county, with town and postcode-level pages — working from your drawings, so location is rarely a constraint.
How much does MEP design cost?
It depends on the size and complexity of the project and how much of the mechanical, electrical and plumbing scope is needed. Send your drawings and we will provide a clear, fixed quote — and good design pays for itself by avoiding costly changes on site.
Ready to talk through your project?
Need MEP design for your project?
Send your floor plans and requirements and we will provide a coordinated, compliant mechanical, electrical and plumbing package — with a fixed quote before any work begins.