Adding more space to your home can feel like a big decision. There are so many ways to approach it with plenty of details to think through. Some people want extra room for family and friends while others hope to boost the value of their property. Each approach brings its own style, process, and promise. The choice often comes down to what matters most to you. Is it price clarity, a quick build, creative design, or simply peace of mind from start to finish? Discovering what sets each option apart makes it easier to picture the kind of extension that would suit you best.
Table of Contents
Reltic Extend
At a Glance
Reltic Extend specialises in bespoke home extensions across London and Surrey, combining over 20 years of local experience with a clear, stage-by-stage pricing approach. They manage design, planning permissions and construction through to aftercare, offering a 10-year structural warranty that underlines their focus on quality and durability. If you want a hassle-minimised project that adds space and value without moving, Reltic Extend is a reliable choice.
Core Features
Reltic Extend delivers end-to-end design and build services tailored to London living, covering rear, kitchen, side, wraparound and double-storey extensions. The company provides transparent, stage-by-stage pricing to remove unexpected costs, handles all planning permissions and building regulations, assigns a dedicated project manager to every job, and uses in-house trades to maintain quality and efficiency. Projects come with a 10-year structural warranty, and the website includes practical tools such as a cost calculator and design tips to help you plan before committing.
Pros
- Two decades of local experience: With over 20 years working on London properties, Reltic Extend understands typical Victorian, Edwardian and modern layouts and how to maximise space and light.
- Transparent pricing model: Their stage-by-stage pricing means you see where your budget goes at each phase, reducing unexpected bills and improving financial control.
- Full planning and compliance handling: They take care of planning permissions and building regulations so you don’t have to navigate complex local authority processes.
- Dedicated project management and in-house trades: A single point of contact and skilled in-house teams reduce delays and improve workmanship consistency.
- Strong customer referral rate: Over 60% of projects come from referrals, indicating high client satisfaction and repeat trust.
Who It’s For
Reltic Extend suits homeowners in London and Surrey who want a tailored, high-quality extension without the stress of managing multiple contractors or navigating planning rules. Families needing extra space, homeowners aiming to add capital value, and property investors seeking compliant, durable improvements will all find the service practical and reassuring. You want expertise and accountability. They deliver it.
No guesswork.
Unique Value Proposition
Reltic Extend stands out through a tightly integrated design-and-build model focused on London’s property market. Unlike outfits that subcontract widely, Reltic keeps trades in-house and assigns a dedicated project manager to ensure timetables and quality standards are met. Their stage-by-stage pricing is not just a sales line; it’s a planning tool that aligns design decisions with budget milestones, so homeowners make informed choices at each stage. Add a 10-year structural warranty and more than 20 years’ local experience, and you get a proposition that prioritises durability, legal compliance and predictability — crucial when working within London’s planning landscape. In short: fewer surprises, superior control, and results that genuinely increase liveability and resale value.
Real World Use Case
Imagine a North London family planning a double-storey rear extension to create an open-plan kitchen-diner and an extra bedroom. Reltic Extend would conduct the initial survey, present staged cost options, manage the planning submission, and deliver the build with an assigned project manager and in-house teams, aiming to minimise disruption and maintain clear communication throughout.
Pricing
Reltic Extend uses stage-by-stage pricing with no hidden costs; specific itemised figures are not published on the site. This approach provides clarity on when payments are due and what each stage covers, though final costs depend on design choices and project complexity.
Website: https://relticextend.co.uk
LCCL Construction
At a Glance
LCCL Construction is a Finchley-based house extension specialist operating across London and Hertfordshire. They combine design and build services for single and double-storey extensions, wraparounds, side returns, kitchen extensions, loft conversions and rear extensions. Notable for winning a regional LABC award in 2024 and for offering instant online quotes, LCCL positions itself as a full-service, accredited builder with a clear aftercare promise.
Core Features
LCCL provides end-to-end design and build services, handling planning, construction and compliance with government and industry standards. Key features include an online instant quote service for rapid cost indications, full project management by experienced professionals and a 10-year guarantee on work. Their service scope covers common London extension types — from compact side returns to larger double-storey and wraparound projects — which streamlines communication by keeping design and delivery under one roof.
Pros
- Comprehensive service offering: LCCL manages both design and construction, reducing the need to coordinate multiple contractors during an extension project.
- Instant quote facility: The online instant quote service helps homeowners obtain a quick cost indicator without an initial site visit, aiding early budgeting decisions.
- Award-winning workmanship: Recognition as a regional LABC awards winner in 2024 demonstrates peer-reviewed quality on at least one residential extension.
- Experienced project management: The company promises full project management by experienced professionals, which can cut delays and clarify responsibilities.
- Long-term assurance: A 10-year guarantee on work provides homeowners with meaningful aftercare and structural reassurance.
Cons
- Starting price may be significant: Pricing begins from £15,000, which might be a minimal figure for small works but could understate the true cost of larger or complex extensions.
- Limited public pricing detail: The website does not provide detailed breakdowns of typical costs or timelines, making it hard to compare bids before enquiries.
- Geographic limitation: Services are primarily available within London and Hertfordshire, so homeowners outside these areas will need an alternative contractor.
Who It’s For
LCCL is best suited to London and Hertfordshire homeowners and property developers seeking a single point of contact for design, planning and build. If you prefer an awarded, accredited builder with project management included and the reassurance of a decade-long guarantee, LCCL fits well. If you need nationwide coverage or highly transparent fixed-price packages online, look elsewhere.
Unique Value Proposition
LCCL’s main strength is combining award-winning craftsmanship with a streamlined design-and-build workflow and an instant online quoting tool. That mix makes them a practical choice for local homeowners who want professional oversight from concept through completion and value the security of a 10-year guarantee.
Real World Use Case
A Finchley homeowner wanting a rear extension can request an instant quote, book a consultation, and proceed with LCCL’s design and build package. The firm would manage planning compliance, coordinate trades on site and deliver the extension under their 10-year guarantee, simplifying the process for a busy household.
Pricing
Prices start from £15,000, with final costs dependent on project size, complexity and specification.
Website: https://lcclconstruction.co.uk/house-extensions-builders
Plus Rooms
At a Glance
Plus Rooms is a London-based design-and-build company that specialises in bespoke home extensions across multiple boroughs and Surrey. They offer a full end-to-end service from initial concept and planning permissions through to finishing touches, and more than 60% of business comes from referrals—a strong signal of client satisfaction. Their emphasis on clear communication, fixed-price quoting and hands-on project management suits homeowners who want a single point of responsibility. Expect quality workmanship and attention to detail, though projects can occasionally overrun due to unforeseen issues.
Core Features
Plus Rooms provides bespoke design and build services for a wide range of extension types, including side, rear, wraparound and flat-roof options, plus loft and internal reconfiguration works. The firm manages the full project lifecycle: design, planning permissions, construction and decoration, with a focus on high standards and transparent communication. They work across multiple London boroughs and Surrey and promote a fixed-price, detailed schedule approach to quoting that helps homeowners understand costs and timelines before work begins.
Clear process. Solid delivery.
Pros
- Comprehensive end-to-end service: Plus Rooms handles design, planning, construction and decoration, which reduces the need to coordinate separate trades and designers.
- Strong reputation and experience: An experienced team with positive reviews and a high referral rate suggests consistent delivery and client satisfaction.
- Transparent quoting process: The company provides fixed prices and detailed schedules so you can see what you are paying for up front.
- Good project management and communication: Homeowners report clear updates and an organised approach that keeps projects moving.
- High-quality workmanship: Attention to detail and a focus on finish quality are consistent strengths in client feedback.
Cons
- Potential for schedule overruns: Projects can overrun owing to unforeseen circumstances such as supply-chain issues or site discoveries, which may extend completion dates.
- Architect communication could improve: Some clients noted that direct contact with architects was limited and could be made more responsive during the design phase.
- Higher cost than hiring individual trades: Pricing may be higher than appointing separate tradespeople, although the premium covers project management, coordination and quality control.
Who It’s For
Plus Rooms suits London homeowners who want a turnkey solution for extending or reconfiguring their home and who value a single, accountable contractor. If you prefer an organised, managed process with clear quotes and high standards of finish rather than juggling multiple suppliers, this is a sensible choice.
Unique Value Proposition
Plus Rooms’ main strength is its full-service, managed approach combined with a strong local reputation: bespoke design married to hands-on project management, backed by a steady stream of referrals. That mix reduces risk and legwork for homeowners who want a reliable outcome.
Real World Use Case
A family in London wanting to add a rear wraparound extension and reconfigure the ground floor would use Plus Rooms to handle planning applications, design development, structural work and internal finishes—delivering a personalised, high-quality living space without the homeowner coordinating separate trades.
Pricing
Pricing is not specified publicly; Plus Rooms typically provides custom quotes based on project scope. Their transparent, fixed-price quoting model and detailed schedules help you understand likely costs before committing.
Website: https://plusrooms.co.uk
Simply Extend
At a Glance
Simply Extend offers a straightforward route to high-quality home, kitchen and side-return extensions across London and Birmingham. They combine bespoke design and build services with free site surveys, fixed pricing and a 10-year warranty, which makes their offering reassuring for homeowners who want predictable outcomes. Expect a full-service experience from planning through to project management, although timelines can stretch depending on planning permissions. Overall: dependable, transparent and well suited to London homeowners seeking a tailored extension.
Core Features
Simply Extend specialises in bespoke extension projects, collaborating with architects to deliver design and build services that reflect each homeowner’s brief. The firm provides free site surveys and quotes, fixed-price proposals to avoid cost surprises, and a 10-year warranty on completed extensions. They cover a broad range of extension types — rear, wraparound, side-return, single and double-storey, flat and pitched roofs, timber cladding and more — and back projects with dedicated project management and customer support. Design ideas and planning guidance are available online to help you shape the brief before work begins.
Pros
- Clear fixed pricing: Their fixed-price approach means you can budget with confidence and avoid unpleasant surprises during construction.
- End-to-end service: They handle design, planning guidance and construction, which simplifies the process for homeowners who prefer a single point of contact.
- Architect collaboration: Working with architects produces customised, practical layouts that make the most of London properties and varying footprints.
- Free site survey and quote: The complimentary survey is a useful first step that saves you time and gives an early sense of feasibility and cost.
- Long warranty: The 10-year warranty provides tangible peace of mind on structural work, which is a real plus when investing in an extension.
Cons
- Limited geographic reach: Simply Extend operates mainly in London and Birmingham, so homeowners outside these areas may not be served.
- Variable timelines: Project durations can extend, particularly if planning permission or party-wall matters arise, so expect potential delays.
- Scope clarity: The service profile focuses on extensions; it is not explicit whether wider renovation or alternative construction works are routinely undertaken.
Who It’s For
This service suits homeowners in London and Birmingham who want to add space, improve layout and increase property value without juggling multiple contractors. If you prefer a managed process with architectural input, fixed budgets and a warranty, Simply Extend matches that brief nicely. Families, growing households and investors looking to unlock more usable space will find this especially relevant.
Unique Value Proposition
Simply Extend’s strongest point is its combination of bespoke, architect-led design and fixed-price, warranty-backed construction — all delivered as a single managed service. That blend reduces the friction of coordinating designers, builders and approvals, offering clarity and accountability from survey to handover.
Real World Use Case
Imagine a South London family commissioning a rear extension to create an open-plan kitchen-diner and additional living area; Simply Extend would run the site survey, develop plans with an architect, manage planning where needed, and deliver the build on a fixed quote, leaving the homeowners with a usable, warranty-backed extension.
Pricing
Fixed prices are offered to avoid surprises; exact costs depend on the size, type and complexity of your project. A free site survey and quote provides the specific pricing information you need to decide.
Website: https://simplyextend.co.uk
Home Extension Team
At a Glance
Home Extension Team, established in 1989 and based in Hertfordshire, is a full-service extension and renovation specialist that manages projects from concept to completion. Their portfolio of over 2,000 projects underpins a reputation for reliable craftsmanship and managed delivery. If you want a single company to handle design, planning and construction with staged payments and insured work, they are a strong contender. Expect clear process control, but do ask early about geography and timings.
Core Features
Home Extension Team provides a free consultation and a feasibility study complete with visuals and floor plans, followed by design finalisation and technical drawings. They handle planning and building regulation management, then move to on-site management with regular visits to ensure quality and adherence to budget. The service is intentionally end-to-end, so you deal with one team from initial idea through to handover.
Pros
- Comprehensive end-to-end service covering design, planning, and construction: you get a continuous workflow from first sketch to finished extension, which reduces the coordination burden on you.
- Strong local reputation with over 2,000 projects completed: this deep portfolio suggests repeatable processes and practical experience across common UK house types.
- Use of top local contractors and insured work with warranties: projects are subcontracted to vetted local trades and carry insurance and warranties for peace of mind.
- Customised designs within client budgets: the team emphasises tailoring proposals to what you can realistically afford, helping avoid scope creep.
- Clear staged payment process for financial control: staged payments give transparency and a way to align payments with progress on site.
Cons
- Specific service areas may be limited to Hertfordshire, which means homeowners outside that region should confirm coverage before proceeding.
- Details on pricing are not explicitly mentioned and may vary per project, so you must request a detailed estimate during the consultation.
- Potentially longer lead times depending on project complexity, which could affect families needing quick turnaround for growing space requirements.
Who It’s For
Homeowners in Hertfordshire seeking comprehensive, managed renovations will find Home Extension Team well suited to their needs. It is ideal for families wanting to add bedrooms, extend living areas or convert lofts and garages without juggling multiple contractors. You want one accountable partner who will handle planning and regulations as well as construction.
Unique Value Proposition
The firm’s value lies in a single-provider model: design expertise, planning management and on-site delivery under one contractual umbrella, backed by a large project history and formal warranties. That reduces friction, clarifies responsibility and helps protect your budget.
Real World Use Case
A Hertfordshire family required a double-storey extension to add a bedroom and larger living space; Home Extension Team ran the feasibility, produced plans, obtained approvals and managed construction to deliver the extension within the agreed budget and schedule — a seamless transformation with one point of contact.
Pricing
Pricing details are not explicitly provided; costs typically depend on the scope of the project and are discussed during the consultation. Expect a bespoke estimate after the feasibility study.
Website: https://homeextensionteam.co.uk
Simply Extend
At a Glance
Simply Extend offers a clear, professional route for homeowners in London and Birmingham who want bespoke home, kitchen and side‑return extensions. The company provides a full design‑and‑build service, fixed prices and timescales, and a 10‑year structural warranty, which together reduce the common stress points of large renovations. There is a strong emphasis on transparency through free site surveys and quotes, though detailed material specifications and exact pricing are not published online. Overall: reliable process, good coverage, and reassuring guarantees — with a few gaps in online detail.
Core Features
Simply Extend specialises in bespoke extension projects, covering rear extensions, kitchen enlargements and side returns with an end‑to‑end service from initial survey through to handover. Key features include fixed prices and timescales so you know the budget and schedule up front, a 10‑year warranty on structural work for peace of mind, and a complimentary site survey and quote to help you decide whether an extension is feasible. The offering is geared towards urban properties in London and Birmingham and focuses on turning planning and design choices into a managed construction programme.
Pros
- Experienced in multiple extension types: The company has a track record across home, kitchen and side‑return projects, which helps when adapting designs to constrained urban plots.
- Bespoke designs tailored to your needs: Simply Extend emphasises custom designs, so extensions are shaped around your family, light and circulation rather than one‑size‑fits‑all plans.
- Clear pricing and planning process: Fixed prices and timescales reduce uncertainty and make it easier to plan finances and timelines.
- Strong customer testimonials: Positive client feedback suggests reliable project management and satisfactory outcomes for many homeowners.
- Coverage across London and Birmingham: Servicing both cities widens access for urban homeowners seeking professional extension teams.
Cons
- Limited information on specific materials used: The website does not detail the brands or grades of structural and finishing materials, making it harder to compare build quality on paper.
- Pricing details are not explicitly listed on the website: While prices are fixed once agreed, there is no published price guide to help you gauge likely ballpark costs before arranging a survey.
- Focus is mainly urban (London and Birmingham): If you live outside those areas, Simply Extend may not be a practical option, limiting choice for homeowners in surrounding counties.
Who It’s For
Simply Extend is ideal for homeowners in London or Birmingham who want a managed, bespoke extension with transparent milestones and a structural warranty. If you favour a single provider to handle design, permissions and construction, and you value clear timelines and a guaranteed warranty, this company fits well. You should be prepared to request a survey to obtain exact costs.
Unique Value Proposition
Simply Extend packages bespoke design with fixed pricing, a 10‑year structural warranty and free initial surveys, which together reduce financial and scheduling uncertainty — a persuasive combination for busy urban families who want an upgrade without protracted negotiations.
Real World Use Case
A South London family commissions a rear extension to create an open‑plan kitchen and dining area; Simply Extend conducts a free site survey, provides a fixed price and schedule, manages planning and construction, and hands over a finished space covered by a 10‑year warranty — keeping the process straightforward for the family.
Pricing
Fixed prices and timescales are offered, but specific costs are project dependent and not listed on the website; you will need a site survey and bespoke quote to know the exact price.
Website: https://simplyextend.co.uk
The Market Design & Build
At a Glance
The Market Design & Build presents as a full-service design and build specialist for London homeowners who want extensions, loft conversions or bespoke new builds. Its in-house team and catalogue of over 700 positive Checkatrade reviews, together with a 5-star Google rating, point to consistently high client satisfaction. Information on pricing and precise project timeframes is scarce on the website, so expect to request bespoke quotes. Overall: dependable craftsmanship and end-to-end management, but limited upfront cost transparency.
Core Features
The company offers genuine end-to-end design and build services, covering initial consultation, planning submissions, detailed design, and project execution on site. It specialises in loft conversions, house extensions, roofing works and new builds, delivering bespoke solutions with an in-house professional team rather than subcontract-only delivery. The emphasis is on managing the whole process for the client — from drawings to finishes — which reduces the number of contacts you need to manage and helps keep responsibility clear.
Pros
- Comprehensive end-to-end service means you deal with a single supplier from concept to completion, simplifying communication and accountability.
- An experienced in-house team provides continuity across design and construction phases, reducing handover friction and improving build quality.
- Strong reputation with over 700 positive Checkatrade reviews and a 5-star Google rating demonstrates reliable client satisfaction and repeat referrals.
- A wide range of services, including loft conversions, extensions, roofing and new builds, lets the company tackle complex or mixed-scope projects within the same contract.
- Proven ability to manage bespoke projects and refurbishments shows flexibility for distinctive designs rather than one-size-fits-all solutions.
Cons
- The website does not specify exact pricing, which means you will need to contact the company for a bespoke quote and cannot easily compare costs online.
- Limited detail on typical project timelines or standard cost estimates may make initial budgeting and planning more difficult for homeowners.
- There is no specific information about eco-friendly or sustainable building options, so clients requiring low-carbon or energy-efficient solutions should confirm capabilities directly.
Who It’s For
This firm suits London homeowners or property developers seeking a single, accountable partner to deliver a loft conversion, rear extension, or even a new build. If you want an in-house team to handle planning, design and construction with a strong track record of positive reviews, this is a sensible choice. If you need instant price transparency or documented sustainability credentials, plan on extra enquiries.
Unique Value Proposition
The Market Design & Build’s strongest selling point is its in-house, full-service approach combined with a proven record of client satisfaction in London. That combination reduces project complexity and delivers a single point of responsibility for design quality and construction execution.
Real World Use Case
A London homeowner wants to add a usable loft room and improve property value without juggling multiple trades. The Market Design & Build would handle planning, structural design, permissions, construction and finishes, managing the schedule and trades so the owner can continue daily life with minimal disruption.
Pricing
Not specified on the website — all pricing is provided via bespoke quotation following an initial consultation.
Website: https://themarketdesignbuild.com
Home Extension Services Comparison
This table provides an overview of various home extension services available. It allows you to compare their key features, pros, cons, pricing, and target areas to help you make informed decisions.
| Company | Key Features | Pros | Cons | Pricing and Area |
|---|---|---|---|---|
| Reltic Extend | Bespoke design & build, stage-by-stage pricing, 10-year warranty | Local expertise, transparent pricing, dedicated project management | Not explicitly listed on pricing | Not specified; London & Surrey |
| LCCL Construction | Design & build, online quotes, 10-year guarantee | Comprehensive service, instant online quotes, award-winning | Potentially high starting price | Starts from £15,000; London & Herts |
| Plus Rooms | End-to-end service, bespoke designs, fixed-price quotes | Strong reputation, attention to detail, high-quality workmanship | Possible schedule overruns | Not specified; Multiple London areas |
| Simply Extend | Free site survey, fixed prices, 10-year warranty | Clear pricing, architect collaboration, end-to-end service | Limited geographic reach | Not specified; London & Birmingham |
| Home Extension Team | Free consultation, full-service end-to-end, staged payments | Large project history, insured work, local contractors | Limited to Hertfordshire area | Not specified; Hertfordshire |
| The Market Design & Build | In-house services, over 700 positive reviews, bespoke solutions | Comprehensive service, experienced team, strong client reputation | No price transparency | Not specified; London |
Discover the Best Approach for Your Home Extension Journey
Choosing the right home extension company is a vital decision for any homeowner looking to increase space, improve lifestyle, and add value without the headache of managing multiple contractors or unexpected costs. The article highlights common challenges such as lack of pricing transparency, navigating planning permissions, coordinating trades, and ensuring quality workmanship backed by solid warranties. If you want to avoid these pitfalls and enjoy a smooth, clear process tailored to London and Surrey properties, consider a specialist with proven local expertise and a transparent, stage-by-stage pricing method.
At Reltic Extend you gain over 20 years of trusted experience combined with full project management from design and permissions through to build and aftercare. Explore practical ideas with our Extension Inspiration & Ideas for Your Home and learn how to plan your project with expert Design & Build Tips for Home Extensions. Ready for your bespoke space transformation? Contact us today for a personalised consultation and benefit from a 10-year structural warranty that guarantees peace of mind. Take the first step toward a confident, controlled, and stylish home extension by visiting https://relticextend.co.uk/contact-us now.
Frequently Asked Questions
What factors should I consider when choosing a home extension company in 2025?
Choosing a home extension company involves considering factors like their experience, reputation, transparency in pricing, and the scope of services they offer. Assess these elements to ensure they align with your project needs and expectations.
How can I prepare for a home extension project?
To prepare for a home extension project, start by assessing your current space and defining your goals. Create a list of must-haves and preferences, and gather ideas and inspiration to discuss with potential contractors when you seek quotes.
What is the typical timeline for a home extension project?
The timeline for a home extension project can vary, but most projects take between 3 to 6 months from initial consultation to completion. Communicate clearly with your chosen company to establish a realistic time frame based on your specific project details.
How does the pricing model typically work for home extension companies?
Many home extension companies use a stage-by-stage pricing model, which breaks the project costs into clear phases. Ask for a detailed breakdown of the costs associated with each stage to avoid unexpected fees during the project.
What should be included in my contract with a home extension company?
Your contract should include details on the scope of work, timelines, payment schedules, and warranties. Ensure that everything is documented to protect your investment and clarify your expectations throughout the project.
How do I ensure quality control during my home extension?
To ensure quality control during your home extension, consider appointing a dedicated project manager from the company. Regularly communicate with them and request updates on progress and any quality checks undertaken, to maintain standards throughout the build.
