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Loft Conversion Company London Lccl Construction

London and Hertfordshire, UK Loft Conversions

Dormer Loft Conversions

Hip to Gable Loft Conversions

L Shaped Loft Conversions

Mansard Loft Conversions

LABC Registered Partner Lccl Construction
Lccl Construction National Federation of Builders
Planning portal
Lccl Construction on Trustpilot
Lccl Construction Building Excellence LABC Awards 2023
Lccl construction on Houzz

5 star rating

  • Instagram


Live Projects

Welcome to Lccl Construction Loft Conversion Company London Limited, Loft conversion company, House extension builders, Architectural design services

Transform your home into your dream space with Lccl Construction Loft Conversion Company London Limited! Our experienced team specializes in loft conversions, house extensions, and architectural design services to help you create the perfect living space. Let us bring your ideas to life!

Your trusted local architecture and construction company in London and Hertfordshire 

Covering London, United Kingdom and Surrounding Areas

Lccl Construction Design And Build
Loft conversion company London
Rear house extension builders London

Specialist Design and Build Construction Company 

Lccl Construction Loft Conversion Company London is your go-to architecture and construction service provider. We specialize in home-improvement projects such as loft conversions, house extensions, architectural design, house renovations and offer our services in an 85 mile radius from our offices location in Finchley, London, meaning you're never far away from our team of experienced professionals.

Architectural design and construction of house extensions. Rear single storey house extensions, side house extensions, wrap around house extensions, side return house extensions, two storey house extensions. We design and build house extensions in London and Hertfordshire.

Architectural design and construction of loft conversions. Dormer loft conversion, hip to gable loft conversions, L-shaped loft conversion, mansard loft conversion or velux loft conversion. We design and build loft conversions in London and Hertfordshire.

Architectural design services for loft conversions, house extensions and new build houses. Complete consultation package London and Hertfordshire, United Kingdom.

Renovation company London, total renovation solutions, including kitchen renovation, bathroom renovation London and Hertfordshire, United Kingdom.

We can serve party wall notices, serve full party wall awards, liaison with 3rd party surveyors. Our party wall agreement services are conducted by surveyor who is MCIOB and FPWS accredited.

Find out more about our construction process and stages, how do we go about running our construction project and what are the core elements associated in the construction process.

We can project manage your project on your behalf, with our construction management services we build loft conversions, home extensions, renovations and new builds.

Our structural engineers produce structural design and structural calculations for your loft conversion, home extension, renovation or new build. 

New build scheme solution, we design and build your new house, our solutions of architecture and construction for new build homes, find out more.

Get instant quote for your loft conversion, home extension, upward home extension, renovation or new build including architecture and design build

Types of projects we do including architecture and construction, get your instant design and build quote 

rear home extension

House extensions

Rear home extension

Side home extension

Side and rear extension



Two storey side

Two storey rear

Two storey wrap

First floor extension

Upward extensions

loft conversion company

Loft conversions

Dormer loft conversion

Hip to gable loft conversion

L shaped loft conversion

Mansard loft conversion

Velux loft conversion

Renovation cost


Flat or apartment renovation

House renovation

Commercial to residential conversion including design and build 

Bathroom renovation

Kitchen renovation

New build cost

New build

Detached homes

Terraced homes


Book consultation call for new build projects.

book consultation call

Basement conversion cost


Basement conversion 

Full house basement

Part house basement 

Outrigger basement

Get a free instant quote or book a free consultation call


Architecture and Construction Services

Lccl Construction unique construction process and design and build process for loft conversion and home extension 

Find out more about Lccl Construction unique construction process or design and build process and what happens on the design or construction stage. 

Step by step explanation of loft conversion, home extension and new build design and construction process. 

We have included our original project images taken on our construction projects.

Lccl construction loft conversion company design and build in London and Hertfordshire, United Kingdom is a specialist loft conversion company, house extension builders, architectural designers and planning company. With our end to end services we successfully start and finish every one of our projects. With our design and build construction company services we can complete all the stages of your build from consultation, architecture, survey to construction including plumbing and electrical installations under one roof. Our combined services includes planning, architectural design and construction. 

By providing services from start to finish we will deal with architecture, planning applications, planning negotiations, building control drawings, building control application, party wall survey and agreements, structural and construction drawings, production of the construction schedule, interior design, construction phase, dealing with building control during construction, electrical and plumbing installations, completion of the construction, certificate and Local Authority Building Control sign off. 

Loft Conversion Company London Limited trading as "Lccl Construction" Registration: 11713461

We cover all areas in London, Hertfordshire, United Kingdom. Our offices are located in 3rd Floor, Hathway House, Popes Drive, Finchley, London N3 1QF. The radius is 85 miles from our office location. Our phone number is: Phone 020 8037 7332

What is a design and build company?

The design and build concept means that multiple specialist skills and trades are combined into one, from start to finish we will deal with all the architecture, consultation, planning and thereafter the entirety of the  construction, saving both time and capital.

We will help you plan, design and build your house extension or loft conversion every step of the way. 


Find out more about successfully completed Lccl Construction design and build projects portfolio

Design and build company London

Loft conversion company, house extension builders, new builds, architecture services

House extension builders

rear house extension builders

kitchen extension builders

side return extension builders

wrap around and side return house extension 

optional LABC 10 year warranty

plumbing and electrical packages

design and build company in London

New permitted development rules applied

New home builder London, United Kingdom

new home build schemes

design and construction

architecture design and planning 

LABC 10 year warranty

no deposit required

plumbing and electrical packages

New permitted development rules applied

Loft conversion company

dormer loft conversions

hip to gable loft conversions

mansard loft conversions

L shaped loft conversions

velux loft conversion

optional LABC 10 year warranty

plumbing and electrical packages

design and build loft company london

new permitted development rules applied

Home renovation company London

Flat and Apartment Renovations

House Renovations

Design and Build

Plumbing and Electrical 

Supply and Install Kitchens, Bathrooms, Flooring, Doors or Wardrobes

Total finishing options

Design and build company London

design and build company in London, UK

design and build of loft conversions

design and build of house extensions

design and build new houses

optional LABC 10 year warranty

local authority building control partner

party wall and structural drawings and calculations

Architecture design services

Architecture, Design and Planning

Measured building survey

Schematic drawings Consultation and Party Wall Agreements

Project Management

Structural Drawings and Calculations Planning and Building Control Application


measured survey



lead consultant



party wall agreements

structural engineer drawings

Design phase

Construction phase

Your project

Architectural design, survey and construction services under one umbrella

We are your one stop architectural design, survey, project management, construction services company. We take care of everything required for your loft conversion, home extension or renovation project. Meaning we will complete the design phase and construction phase for you, without the need to look anywhere else and you have only one point of contact for everything.

Design phase: 

  • Building measured survey

  • Architecture services

  • Planning application

  • Building control application

  • Party wall agreements 

  • Structural engineers calculations and design

  • Project management

  • Interiors


Construction Phase:

  • Construction of loft conversions and home extensions

  • Project management

  • Logistical supply and coordination

  • Quality control

  • Liaison with building control and inspection

  • Guarantee

Free consultation call

Lccl Construction Loft Conversion Company London provides the highest quality of construction and loft conversion services for homeowners who are looking to upgrade their living space. With a great track record and a professional team of experts, we offer a totally free consultation call to help you talk through ideas, issues and aims for your project. With our professional advice and expertise, you can take one step closer to achieving the home of your dreams! Book a free consultation call now and let us help you make it happen.

Instant quote online

Curious about the cost of your loft conversion, house extension or renovation? With our online quote calculator you can find out anytime of the day or night from the comfort of your own home what the approximate cost of our Architecture services or Design and Build services are. Helping you to make an informed choice about your next steps.

Staggered payments

We do not ask for any large payments up front. Our payments are transparent and divided into reasonable stages. As the work progresses you will make payments relating to the progression of the project. Our payments are broken down into manageable intervals, the payment schedule is produced once you go ahead with our services.

Communication is key

We have created our very own online dashboard. This enables you to easily keep up to date with the progress being made on your project. It also makes it easy for you to get in touch with our team anytime that suits you.

Located in Finchley, London N3

We are local and we cover London and Hertfordshire, this is a major advantage for the smooth running and delivery of your project as we are local to you. We cover an 85 mile radius from our base in Finchley, London N3. We have in-depth knowledge of the London and Hertfordshire area for architecture, survey, loft conversions or home extensions design and build.

Have a building project?

We offer construction services, architectural design services and design & build services combined including:

1. Loft conversions company - (dormer loft conversions, L shape loft conversions, mansard Loft conversions, hip to gable loft conversions or velux loft conversion)

2. House extensions builders - all types (single storey extensions, two storey house extensions, rear and side extensions, side return house extensions, wrap around house extensions, side return single or two storey house extensions)


3. Architectural design and build total project start to finish - design and build of loft conversions, house extensions and new house builds, including M & E and liaising with local planning authority (inc. negotiation, relevant applications and designs) or local authority building control, party wall agreements, administration, project management, interior design and structural/construction drawings.


4. New house builders and residential - we design and carry out construction of new build home projects.

Optional LABC 10 or 12 Year Warranty

We specialise in design and construction of house extensions, loft conversions and new house builds for residential customers.

East Barnet Design and build by Lccl Construction

Before and after project by Lccl Construction design and build

Featured in media:

National Federation of Builders London
Sunday Times London
Evening Standard London
real homes
houzz logo
house beautiful london
metro magazine

Get to know what type of loft conversions and home extensions there are, understand the planning permissions impact of the context.

Lccl Construction project portfolio

In short there are 10 stages of the design and build process. Starting with a contact, consultation, quote, full survey, planning permission drawings, building regulation drawings, structural calculation drawings, party wall agreements and construction.


Lccl Construction is one of the  leading construction companies in North London,construction companies in London and construction companies in Hertfordshire, United Kingdom. We are a specialist loft conversion company, house extension builders, design and build company London. With our architecture services, design and build solutions we are able to deliver any type of loft conversion, house extension, both in the London and Hertfordshire areas.

Have a look at the design and build process stages in more detail lccl construction design and build process

Why choose Lccl construction for your loft conversion or house extension

At Lccl Construction we have carried out many design and build loft conversions and house extension projects in London, Hertfordshire, United Kingdom. We design and build London loft conversions turning them into beautiful spaces. Our aim is to make the process of house extensions or loft conversions as simple as possible, hassle free and stress free for a loft conversion in London and house extension in London.


Some of the customers that live in London and Hertfordshire are looking for extra space due to a growing family or the need for additional space for a home office or some like to invest in their property. Whatever the reason we design and build loft conversions in North London, London and Hertfordshire.

Loft Conversion Company London

7 reasons to choose LCCL CONSTRUCTION

1. Insured, Registered and Accredited Construction Company

2. Total Architecture, Construction and M&E Services Under One Roof

3. Fully Detailed Quotes on Small, Mid & Large Projects

4. Efficient and Professional services

5. Located locally London, United Kingdom 

6. Small Deposit

7. Optional LABC Warranty 10 - 12 years

Design and build of loft conversion and house extension North London project
Happy Customers

What are Lccl Construction customers saying, don't just take our word for it..

read lccl construction reviews

Loft conversion company London

Lccl Construction worked on our loft extension and side return kitchen extension. They started work promptly and finished the project on time. They went above and beyond to cater for our needs and are very knowledgeable. If we were to do another project I would definitely use Lccl Construction again. I would not hesitate recommending this great construction company.

Elizabeth Moss

Lccl construction trustpilot ratings 5star