Modular House Extensions
Add space, value, and light to your home
Adding an extension to your house is a perfect way to ‘Love Where You Live’ – to get the most from your home and the location you know, trust and love.
Extensions will not only add space to your house, but value, too. Modular extensions have a number of benefits over traditional extensions.
Extensions are airy, light and versatile. They can give you that kitchen diner you always dreamt of, that additional bedroom or bathroom that your growing family needs, or an additional room for leisure activities.
Here’s how we, at Modexa Build, work with you to give you the extension of your dreams.
Our Extensions
Modern Modular Extensions Designed Around Your Home
Modexa Build specialise in modern, warm and versatile ‘modular’ extensions. They can be built as either single storey or two storey. All of our extensions are precision-built to exacting standards, whilst our service covers the entirety of the project, from planning to handover.
Extensions are typically built at the back of a property as rear extensions, or as wraparound extensions. They are fully glazed and can be built with Bi-folding or French doors as required.
So, imagine that brand new space, perhaps looking out over your garden…naturally lit and wonderfully warm when needed.
Explore More Ways to Extend Your Home:
Conservatory Conversions
Granny Annexes
Garden Rooms
Why Modular?
A SMARTER WAY TO EXTEND THE PROPERTY YOU LOVE
Modular builds differ from traditional builds in that the construction of the superstructure takes place in a factory off-site. The ‘Superstructure’ includes the walls, roof cassettes and where necessary floor construction. The components are then delivered when they are needed to the site and can be fully constructed in rapid fashion.
Modular extensions are by definition low or carbon neutral, and outperform not only your current dwelling but also traditional extensions when it comes to their thermal properties.
Modular extensions have the longevity of a traditional build and can be made to look just like a brick or stone extension. Other finishes include aluminium and zinc cladding along with oak and cedar cladding.
Faster Construction
Because the structure is built off-site, installation on your property is completed in a fraction of the time compared to traditional building methods.
Precision & Quality
Factory-controlled manufacturing ensures tighter tolerances, better consistency, and a higher standard of finish than on-site construction.
Energy Efficient
Modular extensions outperform many traditional builds with superior insulation, reduced thermal bridging, and improved airtightness.
Low Carbon Approach
With less on-site waste and efficient manufacturing processes, modular construction offers a more environmentally responsible solution.
Modular extensions offer the longevity and appearance of traditional builds — while delivering faster, cleaner, and more energy-efficient results.
Extension TYPES
Which Extension Is Right for You?
A rear extension is just that – an additional space grafted onto the back of an existing building. Alternatively, a wraparound extension will add some side-space as well as space to the rear. Either option will add an elegant addition to your home, depending on the options available in the space that you have. Modexa Build can construct rear extensions, wraparound extensions or two storey extensions.
Rear Extensions
Transform the flow of your home, creating flexible and expansive living spaces.
Wraparound Extensions
Ideal for larger layouts and where more space is available and a more expansive option is required.
Two Storey Extensions
For more ambitious projects, consider a transformative two-storey extension
Not sure which extension is right for your home? Contact us today for a consultation.
Extension sizes
What size extension can you build?
Under UK laws, extensions can be up to 50% of the size of the original property, so really the choice is yours. Modexa Build will construct your extension from 9m2 to 60m2. This means a cosy additional reading room, all the way up to huge multi-purpose rooms or kitchen-diners.
We can offer a variety of sizes and configurations, with finishes to suit your needs and lifestyle.
Kitchen Diners
Living Area
Additional Bedroom
Bathroom/ Ensuite
Home Office
Gym/ Wellness
Garden Area
Need help choosing the right size? Contact our team who can help you decide the perfect extension size based on your home, space, and lifestyle.
Why choose Us?
Why Modexa Build?
First and foremost we are experienced construction experts, capable of handling the entirety of your project, from enquiry, through a proposal, site survey to manufacture and installation.
With decades of experience and dozens of projects, you can trust us to take your vision into reality.
We work right across the North of the UK, and all our customers love our attention to detail and approachable demeanour.
End to End Project Management
From first enquiry to final installation
Decades of Experience
Trusted expertise across every stage
Local & Reliable
Serving homes across the North of the UK
Detail-Focused Approach
Precision and care in every project
Friendly, Professional Team
Easy to work with from start to finish
You will find us professional, amenable and hard-working. Contact us now to have a chat about your plans!
Finishes
Built to Look Exceptional and Perform Better
We offer a full range of interior and exterior finishes, depending on whether you want your extension to blend in with your existing property, or stand out and make a statement! We have experience of a number of aesthetic embellishments depending on your taste.
Here are just some of our options:
Brick Slips
Render
Aluminium Cladding
Zinc Cladding
Timber Cladding
Finally, by combining two or more different materials, we can give your modular extension a unique, bespoke and breathtaking finish!
Take a look at our Guide to Modular Extensions for more information about finishes.
High-Performance
improve your home’s carbon footprint
Our modular extensions are designed to deliver exceptional energy efficiency, improved comfort, and long-term value for your home.
EPC Performance
Modexa’s modular extensions are built using our modular system and are designed to achieve very high EPC ratings, typically A or high B, thanks to precision factory manufacturing, high insulation levels and reduced thermal bridging.
This will be a stand-alone rating and will be added to the main house rating, often meaning your extension will outperform your main house.
Higher EPC ratings mean:
- Lower energy bills.
- Reduced carbon emissions
- Increased property value/ resale value
- Better mortgage and lending options
Air Tightness & Thermal
Because Modexa modular extensions are manufactured in controlled factory conditions, construction tolerances are far tighter than traditional building.
This results in:
- Significantly reduced air leakage
- Improved thermal efficiency
- Consistent insulation installation
- Lower heating demand
Typical modular airtightness levels can be 70% better than many traditional builds.
Renewable Energy Ready
Modexa Modular extensions are designed to integrate seamlessly with modern renewable technologies such as:
- Solar PV systems
- Air source heat pumps
- Smart energy systems
This ensures your extension is ready for the future – High Performance Living.
Build smarter. Live better. Talk to our team now to deliver exceptional energy efficiency.
Pricing
what’s included in the price
Our pricing is based on the size of your extension, giving you a clear idea of costs from the outset. Use the guide below to estimate your project and what’s included as standard.
All prices are estimates and may vary depending on site conditions.
Depth (from existing house) (m) | Length (m) | |||||||
3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
3 | £37,966 | £42,703 | £47,440 | £52,177 | £56,914 | £61,651 | £66,388 | £71,125 |
3.5 | £40,518 | £45,925 | £51,332 | £56,739 | £62,145 | £67,552 | £72,959 | £78,365 |
4 | £43,070 | £49,147 | £55,223 | £61,300 | £67,376 | £73,453 | £79,529 | £85,606 |
4.5 | £45,622 | £52,369 | £59,115 | £65,861 | £72,607 | £79,353 | £86,100 | £92,846 |
5 | £48,174 | £55,590 | £63,006 | £70,422 | £77,838 | £85,254 | £92,670 | £100,086 |
5.5 | £50,726 | £58,812 | £66,898 | £74,984 | £83,069 | £91,155 | £99,241 | £107,326 |
6 | £53,278 | £62,034 | £70,789 | £79,545 | £88,300 | £97,056 | £105,811 | £114,567 |
What's Included
- Foundations*
- Floor slab or sub-floor construction
Eco Rend Accredited render
- Underfloor heating installation to the extension area only
- External walls and primary structure
- Flat roof system
- Supply and installation of one window, one roof lantern and 3-leaf bi-fold door set
- Basic drainage connection and tie-in
- Boarded and skimmed
This package provides a secure, weatherproof structure ready for internal fit-out works.
* Standard foundations assumed until survey on site:
Single Story extension foundations standard = 600mm wide 300mm thick concrete foundation, 1000mm to bottom of foundation.
Double Story extension foundations standard = 750mm wide 300mm thick concrete foundation, 1000mm to bottom of foundation.
What's not Included
- Internal structural alterations and calculations
- Internal walls
- Additional External items (patio, paths etc)
- Electric, plumbing & heating (apart from underfloor heating in the extension)
- Decoration
- Flooring & skirting
- Lighting & sockets
- Kitchen supply & installation
A full package can be undertaken by Modexa build; Pease contact us for further information or a quick estimate.
Benefits
Modular vs Traditional Extensions
See how modular construction compares to traditional building methods across key areas that matter most.
Speed of Construction
Modular
A modular build can be completed up to 70% faster than a traditional build, and with a total lead time of 4-6 weeks
Traditional
Traditional builds are subject to on-site delays. For example, glazing cannot be ordered until the brick is completed
Cost
Modular
You will get a fixed price from Modexa Build, with no hidden charges to worry about
Traditional
Variable costs where the original budget can often be exceeded
Your build time
Modular
All components will arrive exactly on time, when they are meant to, reducing disruption and uncertainty
Traditional
Much more difficult to estimate, leading to delays and protracted build times
Quality
Modular
Built in a controlled manufacturing environment for a consistency of quality
Traditional
Subject to a number of variations, such as labour, material, climate etc
Design
Modular
Manufactured bespoke for every project to meet your exacting needs
Traditional
Custom builds can be slow and lead to additional cost
Energy Performance
Modular
High performance due to minimal air leakage and type of materials used
Traditional
Will exhibit most of the energy loss associated with traditional build
Process Management
Modular
Processes follow similar standards so are streamlined and executed with vast experience
Traditional
Every build is different, each crew can differ, the list of sub contractors can also differ
Site Impact
Modular
Minimal disruption for a shorter amount of time
Traditional
Significant disruption over a protracted period of time
How it Works
How our design and build process works:
1
Consultation
Get in touch with us for an initial, no obligation chat about your potential project. You’ll find us experienced, professional and full of ideas. What do you want from your extension? How is it going to improve your living space?
2
Site Assessment
In order to provide you with an accurate quotation, and discuss your vision in situ, we will visit the site of the proposed build and consult with you about what can be achieved.
3
Design and Quotation
We will provide you with a tailored proposal resulting from our consultation. The proposal will be fully costed and give you accurate information around delivery and lead times, including specifications and technical drawings.
4
Off-site Construction
Whilst the superstructure is being manufactured off-site with our manufacturing partners, we will be preparing your site for delivery, so that, on delivery, everything goes as smooth as possible.
5
Delivery and Installation
With a fully-prepared site now in place, all modules will arrive ready to assemble, with installation fully completed within days.
frequently asked questions
Your Questions, Answered
Here are some of the most common questions about our modular extensions, pricing, and process.
Yes, you can get a mortgage on a house with a modular extension. Modern modular buildings are built to comply with UK Building Regulations, just like traditional homes, so structurally they’re designed for long-term residential use. – lifespan of a 100+ years allows for at least 4 mortgage cycles
It really depends on the size of extension that you want, but it is unlikely that £30k will cover the cost of the build. TAKE A LOOK AT OUR GUIDE TO MODULAR EXTENSION COSTS HERE
It really depends on what you want from your extension. A 3m x 3m extension is perfect, for example, for an additional sitting area facing the garden. A smaller extension like this will cost less, and be cheaper to heat, too
No, if it’s a straightforward 4 m extension at the rear of your house. Your existing house and plot size may change the requirement for planning.
Modular builds are quicker, cleaner and often cheaper than traditional builds. They minimise disruption on site, and help to avoid delays caused by weather conditions. Modular extensions are versatile, precision-built and cost-efficient
Still have questions? Contact our team for friendly advice and guidance.
Questionnaire
Ready to Transform Your Home?
Complete our quick questionnaire and receive a personalised estimate, before you spend money on architects or drawings.