What is a Certificate of Lawfulness?

A Lawful Development Certificate is a legal document stating the lawfulness of the development. By applying for a Certificate of Lawfulness (Proposed), you seek formal confirmation that planning permission is not required. It can be beneficial when you come to sell your property.

Do I need a Certificate of Lawfulness for a loft conversion?

It is not mandatory, but we always advise our clients to obtain one. Solicitors representing a buyer will almost always require documentary evidence that the loft extension is lawful, and the certificate also helps in the event a neighbour queries the work.

How do I get a Certificate of Lawfulness?

We submit an application to your local planning authority through the Planning Portal or council website, alongside drawings of the existing/proposed development and a site location plan. An officer will then assess the application.

How much does a Certificate of Lawfulness cost?

We include the drawings, structural calculations and submit the applications for your LDC and building control. Certificate fees and inspection fees are payable by the client — LDC fees are £135 (you'll receive an email from the planning portal directly). Building control fees vary by borough.

Can the loft conversion be started before the Certificate of Lawfulness has been approved?

We always advise clients to wait until the certificate has been properly issued. It usually takes around 8 weeks for approval after submission.

Do I need to notify my neighbours? (Party Wall Act)

If your home is semi-detached or terraced, you'll need to notify neighbours under the Party Wall Act. Most loft conversions involve alterations to party walls to support steel beams, so a Party Wall surveyor may be required.

What building regulations do I need to consider?

Loft conversions always need building regulations approval, irrespective of whether planning permission is required. We prepare building regulations plans, structural specifications and calculations to ensure compliance.

Loft Conversion Drawings & Plans

Our Loft Plans Package

Fixed Price For Most Properties

At Loft Plans, we provide a comprehensive, fixed-price package for loft conversion architectural drawings and structural calculations, designed to take you from concept to construction seamlessly. With years of experience and in-house building expertise, we simplify the planning process, ensuring everything you need is covered—no hidden fees, no surprises.

And now, with our 3D Visualisation Tours, you can step inside your future loft conversion before construction begins, visualising every detail of your design in stunning 360° clarity.

Planning Drawings

Planning Drawings Only

Ideal if your loft conversion requires a planning application — for example properties in conservation areas, flats, split houses or designs that fall outside permitted development. We produce the existing and proposed architectural drawings needed to submit your application to the local authority.

From£950

Tailored for 2/3/4-bedroom terraced and semi-detached properties across London, Essex and Hertfordshire.

What's included

Full measured survey
Existing floor plans and elevations
Proposed floor plans and elevations
Roof layouts
Site and location plan
Planning application submission & council liaison
Revisions to meet planner feedback

Full Loft Conversion Package

Most loft conversions fall under permitted development — meaning planning permission is effectively guaranteed. That's why we recommend going straight for the full package from the start: everything you need to take your project from concept all the way to construction, with no surprises.

Fixed price from£1500

Tailored for 2/3/4-bedroom terraced and semi-detached properties across London, Essex and Hertfordshire.

Everything in Planning Drawings Only, plus:

Full measured survey
Initial Planning Drawings
Existing & proposed floor plans, elevations, roof layouts, site & location plan.
Liaising with Local Authorities
We handle all planning and approval processes.
Planning & Building Control Applications
Submitted and managed for you.
Building Regulations Drawings
Ensuring compliance with UK standards.
Structural Calculations
Approved by professional engineers for a safe build.

Please note: Our package includes managing your planning and building control applications and liaising with local authorities throughout the process. However, it does not cover the fees charged by your local authority for application submissions.

With years of experience in preparing loft conversion plans and working closely with local councils, we handle all the necessary paperwork and ensure your applications meet regulatory requirements. Our team takes care of the entire process, so you can focus on your loft conversion project with complete peace of mind.

With our package, you'll save money compared to traditional architects or bundled loft conversion services. Plus, you'll have the confidence of knowing your plans are builder-ready, compliant, and expertly designed.

Premium Add-on

3D Visualisation Tour

See your loft before you build it. Bring your loft conversion to life with our 360° 3D Visualisation Tours, allowing you to see and experience your new space before construction begins.

Immersive & Interactive – Walk through your future loft and explore every angle
Plan Your Layout – Visualise furniture placement and bathroom layout
Understand head height and sloping ceilings
Reduce Costly Changes – Identify potential design issues before building starts
Accessible on Any Device – Walk through your future loft from your phone, tablet, or computer anytime, anywhere

Already have loft drawings? We can create a 3D tour using your existing plans — all we need is your loft floor plan and section.

Revisions: Please provide detailed preferences upfront, as revisions will incur additional costs due to the time-intensive process required to implement changes. Given the complexity of creating 360° visualisations, even minor adjustments require significant rework, so it's essential to finalise as many details as possible from the start.

Add 3D Walkthrough+£400

360° View

Click fullscreen icon inside to expand

How it works

Our Process

Our entire process is designed to make things as quick and simple as possible for you. We take on all of the stress, leaving you to just approve the designs and look forward to a new living space inside your home.

After the survey, we will draw up plans of the existing layouts and elevations so that we can progress to the design stage of your new loft conversion.

We will submit the relevant application to the local authority, whether that be an application for a Certificate of Lawfulness (Permitted Development) or a Full Planning Application, and we will monitor this application for you, dealing with any queries the local authority may have.

Standard householder planning approval usually takes around 8 weeks for the local authority to determine. If we already know that your loft conversion application falls under Permitted Development, as most do, there will be nothing to worry about, as we will have created your plans to ensure they comply with Permitted Development requirements.

1
Book a Survey
Our surveyor visits your property to take detailed measurements and assess the conversion potential.
2
Draft Drawings
Receive your first draft plans within 7 days of the survey.
3
Planning Submission
We manage planning and building control applications, handling all queries with local authorities.
4
3D Visualisation (Optional)
Step into your loft design with our immersive 3D Virtual Tours — ideal if you want to visualise the space before fully confirming your layouts.
5
Structural Calculations & Building Regulation Drawings
Once designs are approved, our engineers complete structural calculations and building regulation drawings within a few days.
6
Move to Construction
Once approved, your plans are ready for your builder to start the project.

Why Choose Loft Plans?

We know the loft conversion industry inside out

With years of experience in designing and building loft conversions, what sets us apart is our hands-on construction expertise—having successfully completed hundreds of loft conversions over the years.

This experience means we understand what works, how to maximize your space effectively, and how to tailor designs to fit your budget, especially for more complex projects.

During your survey, we can walk you through your staircase options and determine the best position and design on the spot. This way, you'll have a clear understanding from the very start, avoiding surprises later when you receive your drawings and realize the staircase takes up more space than expected—preventing unnecessary revisions.

Unlike architects who often lack practical building experience and may not consider material and labor costs, we design your loft conversion with real-world construction knowledge. This ensures your plans are practical, cost-effective, and builder-friendly, saving you time, stress, and money.

Most loft conversions fall under Permitted Development, meaning approval is guaranteed as long as your plans meet the necessary criteria.

Where planning permission is required, we handle the entire process, liaising with local authorities to ensure a smooth and stress-free approval.

Book A Survey Now

How We're Different...

No Hidden Fees
Many companies lure you in with cheap initial drawings, then surprise you with expensive add-ons. With us, your complete package includes everything you need to move to the build stage.
Fast Turnaround
Survey within 3 days (subject to access), plans within 1 week of survey, and structural calculations shortly after.
In-house Building Expertise
We've built hundreds of loft conversions, so we know how to design spaces that work for your budget and construction needs.
360° Visualisation Tours
Step inside your future loft conversion before construction begins. Our immersive 3D visualisations let you see every detail in stunning 360° clarity, so you can design with confidence.
Complete Planning Support
We manage every step of your application, including liaising with local authorities to address any queries.

Designs & Styles

Loft Conversion Types

We design all major loft conversion types.

Dormer Loft Conversions

The most popular option, offering increased head height and maximising usable floor space. Perfect for additional bedrooms, home offices, or bathrooms. Often eligible under permitted development.

Pitched Roof Dormer Conversions

Ideal for large footprints or high pitched roofs, and sometimes required in conservation areas. Makes an attractive feature and can be combined for varied designs.

Velux Loft Conversions

A budget-friendly option that retains your existing roof structure with no external alterations. Best for properties with sufficient ridge height.

Hip-to-Gable Loft Conversions

Extends the sloping roof into a vertical wall, transforming the hip end into a gable. Ideal for end-of-terrace or semi-detached homes with a hip roof.

L-Shape Dormer Conversions

Perfect for Victorian and Edwardian properties. Maximises space — often allowing two bedrooms and a shower room. A practical choice for significant added living space.

Mansard Loft Conversions

Built to the rear with a near-vertical back wall and flat top, creating generous, well-proportioned rooms. Box dormer windows sit vertically for plenty of natural light and a seamless look — usually requires planning permission.

Help

Frequently Asked Questions

Under regulations effective from 1 October 2008, a loft conversion is considered permitted development — not requiring a full planning application — subject to limits including a 40 m³ allowance for terraced houses and 50 m³ for detached and semi-detached houses, no extension beyond the principal elevation, no extension higher than the existing ridge, similar materials, and side windows being obscure-glazed. Permitted Development Rights are granted by parliament rather than the local authority. We always advise obtaining a Lawful Development Certificate, which we apply for as part of our service.

Get in touch

Book your survey today

Send us a few details about your property and we'll get back to you to arrange a survey, usually within a few hours (subject to access).

Service area: Essex, London & Hertfordshire
Email: loftplansuk@gmail.com
WhatsApp: 07818 321263
Turnaround: Drafts within 7 days of survey

Loft Conversion Drawings & Plans Essex, London & Hertfordshire