A professionally designed loft conversion adding extra living space and value to a home.

Loft conversions

Putting that unused space to good use can create more family space and add value to your property. When designed correctly, a loft conversion becomes a smart and practical addition to your home.

What is a loft conversion

A loft conversion transforms the space you already have into a usable, functional living area. This space is often just used for storage and may house a boiler or water tank. It’s an ideal way to create a new bedroom, home office, master suite with an ensuite, guest room, and more. There are several ways to extend your loft space, and we’ll guide you through the options.

Staircase for loft conversion?

Adding a staircase is never an issue—there’s always a way to design it so it fits seamlessly without encroaching on other bedrooms. Working with a loft conversion architect ensures the new space feels like a natural part of your home. We can also assist in finding loft conversion builders to bring your project to life.

Modern loft conversion in Chelmsford, Essex, designed by Kirkwood Architects on Broomfield Road for homeowners James and Sarah.
Spacious loft conversion in Brentwood, Essex, featuring a master bedroom with en suite on Shenfield Road, designed by Kirkwood Architects for homeowners Mark and Laura.

Types of loft conversions

There are many types of loft conversions, but no two roofs are the same. Arguably the most common option is adding a dormer to the front, rear, or side. If you have at least 2.1m of headroom, the simplest solution is installing skylights and fitting out the loft with plasterboard and flooring while keeping the existing structure.

Do we need an Architect?

A set of drawings is still required for approval and to ensure a smooth, successful build. Working with a loft conversion architect in Essex will help you design a conversion that blends with your home. Here are some common loft conversion styles and their uses. Click here to see the areas we cover.

Skylight/Room in loft conversion

Sometimes, the simplest option is the best. A skylight loft conversion, also known as a ‘room in loft’ or ‘Velux’ conversion, keeps the existing structure intact while upgrading the flooring, insulation, walls, and windows. It’s the most budget-friendly type of loft conversion but requires a minimum of 2.1 metres of headroom. If the space is available, it’s a smart choice with great potential. With minimal conversion costs, you could add an extra bedroom, increasing your property’s value beyond the cost of the build.

Benifits of a good architect

Working with a loft conversion architect in Essex ensures the design is both practical and compliant with building regulations. We can assist with build costs for loft conversions in Essex—just let us know what you’re planning, and we’ll advise on the best steps to take and build costs, free of charge.

Stylish loft conversion in Billericay, Essex, featuring a master bedroom with en suite on Norsey Road, designed by Kirkwood Architects for homeowners Tom and Rebecca.

Dormer loft conversions

Dormer loft conversion is a cost-effective and popular way to extend your home by adding a box-shaped structure to a sloping roof. This extension increases both headroom and floor space while allowing for the installation of traditional windows, bringing in more natural light. Homeowners often choose dormers because they provide a spacious feel without the higher costs of other loft extensions. Now dormers come in various sizes, styles, and shapes, so getting the design right is crucial.

Increase property value

Any well-planned dormer can improve your home’s overall look and kerb appeal, while a poorly designed one may stand out in the wrong way. The challenge is balancing maximum internal space with a proportionate and seamless design that complements the existing house. Done right, a dormer loft conversion transforms your loft into a bright, functional, and valuable living area.

Modern loft conversion in Hornchurch, Essex, featuring a master bedroom with en suite on Wingletye Lane, designed by Kirkwood Architects for homeowners Adam and Sophie.

Hip-to-gable loft conversion

Hip-to-gable loft conversions are commonly chosen for end-of-terrace, semi-detached, and detached homes. This conversion changes a hipped roof into a gable by straightening the sloped side into a vertical wall, creating more internal space. To maximise the area even further, some homeowners combine this with a dormer extension—though this approach can push costs into the six-figure range.

Mansard loft conversions

These are ideal for those wanting a more classic look. This type of extension involves raising the shared party wall to create a near-vertical outer wall, usually sloped at around 72 degrees, with a flat roof on top. Councils often look more favourably on mansard conversions as they help maintain the traditional character of a building. They’re typically added to the rear of a property and can significantly increase loft space, making them a great option for larger extensions. Working with a loft conversion architect ensures the design is both practical and suited to your home’s structure.

Stylish loft conversion in Maldon, Essex, featuring a master bedroom with en suite on Fambridge Road, designed by Kirkwood Architects for homeowners Daniel and Lucy.
Contemporary loft conversion in Leigh-on-Sea, Essex, featuring a master bedroom with en suite on Marine Parade, designed by Kirkwood Architects for homeowners Ben and Emily.

What options do you have based on your house

Essex loft conversions can be a flexible and efficient way to make the most of your existing living space, with various design options suited to different property types. If you’re planning to utilise permitted development rights or simply want a conversion that seamlessly integrates with your home, certain styles may work better for specific house types.

Terraced Homes

Terraced properties can often benefit from permitted development rights, but any extension must comply with relevant design regulations while also considering the impact on neighboring homes. Under permitted development guidelines, a loft conversion for a terraced house cannot exceed 40 cubic meters, nor can it extend beyond the highest point of the roof or that of the adjoining properties.

Party walls

Since terraced homes have two connected party walls, securing agreements with both neighbors may be necessary. If either neighbor objects, you could face additional legal hurdles, so a simple room-in-the-attic conversion or a modest dormer addition may be the most straightforward approach. Working with an architect in Essex ensures your design meets regulations while maximizing space.

Semi-Detached Homes

Semi-detached houses offer more flexibility compared to terraced properties. Permitted development allows up to 50 cubic meters of additional space, enabling larger-scale loft conversions. With a shared party wall already in place, a mansard-style conversion could be a suitable option, especially in conservation areas where maintaining a traditional appearance is important for planning approval. Loft conversions Essex specialists can help navigate the planning process to ensure a smooth build.

Detached Homes

Detached properties provide the greatest freedom when it comes to loft conversions. Now if your home has a low-pitched hipped roof, a hip-to-gable conversion can open up the roofline, often allowing space for a dormer extension as well. While detached homes typically avoid party wall issues, permitted development rights still come with guidelines that must be met.

Listed Buildings

Additional restrictions may apply for listed buildings and properties located in conservation areas, so it’s essential to thoroughly review the planning requirements before starting the project. Consulting a home extension architect can help you design a loft conversion that blends seamlessly with your property.

Stylish loft conversion in Chelmsford, Essex, featuring a master bedroom with en suite on Roxwell Road, designed by Kirkwood Architects for homeowners James and Sophie.
Modern loft conversion in Brentwood, Essex, featuring a master bedroom with en suite on Hutton Road, designed by Kirkwood Architects for homeowners Tom and Rebecca.
Modern loft conversion in Grays, Essex, featuring a master bedroom with en suite on Lodge Lane, designed by Kirkwood Architects for homeowners Daniel and Charlotte.

What are the loft conversion building regulations?

All loft conversions and homes must comply with building regulations, ensuring projects meet safety and structural standards. Your plans will need to be assessed either by local building control or an approved inspector, who will review both the loft space and the staircase.

Loft Conversion Building Regulations

At a minimum, a structural engineer is required to provide key calculations, but going further with a building regulations package is highly recommended. This package provides all the necessary details for contractors, covering areas such as fire safety, ventilation, drainage, soundproofing, insulation, and structural stability.
One of the biggest considerations is insulation, as most heat escapes through the roof. A loft conversion helps retain warmth, but high-quality insulation is essential to achieve the best results. Regulations require a U-value of at least 0.16W/m2K, though aiming for a higher level is beneficial.
Building regulations also ensure your project meets structural and fire safety standards. This includes checking if the new floor is strong enough, whether the roof structure remains stable, and how escape routes are planned. Staircases must be designed safely, and sound insulation should be considered to minimize noise transfer between the new and existing spaces.

Floor Joist Regulations

Since most lofts were not originally built as living spaces, their ceiling joists often aren’t strong enough to support a usable floor. Different joist sizes are required depending on the span:
47 x 145mm joists: span up to 2.89m
47 x 170mm joists: span up to 3.38m
47 x 195mm joists: span up to 3.87m
72 x 145mm joists: span up to 3.33m
72 x 170mm joists: span up to 3.89m
72 x 195mm joists: span up to 4.44m
Additionally, at least 100mm of insulation between joists is required for soundproofing.

Fire Safety in Loft Conversions

Fire safety is a critical aspect of loft conversions. Key requirements include:
Fire doors: Existing loft doors must be replaced with fire-resistant doors that can withstand heat for 20-30 minutes, allowing safe escape.
Smoke alarms: A smoke alarm must be installed in the new loft space and linked to the main system.
Fire containment: Walls must be fire-resistant to help limit the spread of fire.
Sprinklers: Not required under regulations but can be installed for added safety if the home’s water pressure is suitable.
Because of the detailed requirements involved, multiple specialists, including a structural engineer, may be needed. The project will then be assessed by building control or a private inspector to ensure compliance.

Modern loft conversion on Marine Parade, Leigh-on-Sea, Essex, designed by Kirkwood Architects for homeowners Ben and Emily.
Expert architectural design service for loft conversions in Essex by Kirkwood Architects, creating bespoke and functional living spaces.
Stylish loft conversion in Rayleigh, Essex, featuring a master bedroom with en suite on London Hill, designed by Kirkwood Architects for homeowners Chris and Hannah.

How much does a loft conversion cost?

Understanding the cost of loft conversions in Essex is essential before starting your project. Prices can vary based on factors such as size, design, and material quality. On average, a loft conversion in Essex costs between £55,000 – £120,000, but depending on the specifics, the price can range from £45,000 to over £200,000.

Type of loft conversion

The type of loft conversion you choose will significantly impact the budget. A basic room-in-loft conversion can start from as little as £25,000, while more complex designs, such as hip-to-gable with dormers, can exceed £200,000. Choosing the best option depends on your budget and the space you need.

Structural Engineering

To get an accurate estimate for your project, it’s important to consider costs for materials, structural engineering, and professional fees. Working with an architect in Essex or a home extension architect ensures your design is both practical and cost-effective while meeting all building regulations.

Modern loft conversion in Upminster, Essex, featuring a master bedroom with en suite on St. Mary's Lane, designed by Kirkwood Architects for homeowners Ryan and Jessica.
Loft conversion service in Leigh-on-Sea, Essex by Kirkwood Architects

Does a loft conversion require planning permission?

One of the first things to consider when planning a loft conversion in Essex is whether you need planning permission. The answer isn’t always straightforward, as it depends on the type of conversion, the size, your property type, and where you live. Some projects can go ahead under permitted development rights, while others will require full planning approval.

Permitted Development Rights for Loft Conversions

Permitted development rights allow certain loft conversions to proceed without needing planning permission, provided they meet specific criteria:

  • Detached and semi-detached homes can add up to 50 cubic metres of extra space.
  • Materials used must match the existing property.
  • No raised roof ridges—any extension must stay below the highest part of the roof.
  • Any dormer walls must be set back at least 20cm from the original wall.
  • Side windows must be frosted and non-opening if below 1.7m from floor level.

These rules apply to the original house, meaning if a previous owner has already extended the loft, that space counts towards the permitted volume. If your home meets these criteria, you may not need planning permission, but it’s always best to consult a loft conversion architect in Essex to ensure compliance.

When Planning Permission is Required

Not all homes qualify for permitted development. You’ll need full planning permission if your property is:
  • A flat or maisonette
  • A listed building
  • Located in a conservation area

Additionally, certain loft conversions in Essex may require approval, depending on the design. Loft Conversion Types and Planning Permission:

  • Roof Light Loft Conversion – No structural alterations, just new windows and flooring. Usually doesn’t require planning permission.
  • Dormer Loft Conversion – Extends from the existing roof slope, creating extra headroom and space. Often falls under permitted development.
  • Hip-to-Gable Loft Conversion – Converts a sloping end roof into a vertical wall. May require planning permission.
  • Mansard Loft Conversion – Alters the roof structure significantly, typically requiring planning approval.

Lawful Development Certificate

Even if your loft conversion in Essex falls under permitted development, obtaining a lawful development certificate from your local authority is highly recommended. This certificate proves that your project complied with regulations at the time of construction, protecting you from future legal issues or changes to planning rules.
To avoid costly mistakes, working with an experienced home extension architect ensures your design is legally compliant and maximizes your loft space efficiently.

Stylish loft conversion in Thundersley, Benfleet, Essex, designed by Kirkwood Architects for homeowners Paul and Hannah.
Modern loft conversion in Wickford, Essex, designed by Kirkwood Architects for homeowners Daniel and Sarah.
Contemporary loft conversion in Benfleet, Essex, featuring a master bedroom with en suite on Essex Way, designed by Kirkwood Architects for homeowners Matt and Sophie.

We've left some good impressions

See what our customers in Essex are saying on

Jack Dev
08:58 04 Mar 25
I was looking for an architect in Billericay and came across Kirkwood. They designed my single-story rear extension, which includes an open-plan kitchen and an internal knock-through. The architects and structural engineers were fantastic and really understood what I wanted to achieve. Kirkwood also put me in touch with local builders who were reasonably priced and completed the extension without any fuss. If you’re looking for a reliable Essex architect serving Billericay, I’d definitely recommend Kirkwood.
Maria Krystal Humphrey
11:20 03 Feb 25
We had a single-story house extension built in Thurrock, Essex, by the builders that Kirkwood passed us onto. Kirkwood's architects did a really good job, so we were pleased we went to them rather than a design-and-build company that just subcontracts the architectural work out.
Grace Biddiss
09:27 02 Feb 25
We appointed Kirkwood as our architects for a double story and wrap around kitchen extension in Billericay, Essex. They provided us with architectural plans, structural engineering and building regulation drawings. The team was professional from start to finish and the builder they recommended has done a faultless job. You definitely get what you pay for, highly recommend. Thanks!
Freyja
19:14 01 Feb 25
We’ve worked with residential architects before, but Jamie and his team, especially Nathan, were fantastic. Kirkwood designed plans for our double-story side extension, loft conversion, and single-story rear kitchen extension, and we knew we had to choose the right company since it involved our entire home.Based in Brentwood, Essex, we were also introduced to builders and tradespeople through Kirkwood, and they were excellent—professional, respectful, and a pleasure to work with. If we ever take on another project, we wouldn’t hesitate to use them again.
Harry
14:41 01 Feb 25
I was skeptical about Kirkwood’s 5 star reviews but now I’m one of them. Incredible service, especially for the money we paid. They wasn’t the most expensive but for the standard of service we received, they defiantly should have been. They done the architectural plans for our home extension in Chelmsford. The architect was amazing at creating our open plan kitchen and dining area. The structural engineer was quick, polite and drunk tea like it was going out of fashion. Strongly recommend if your considering a architect for your home extension in a Chelmsford.
Riley Russell
13:58 31 Jan 25
Kirkwood done a fantastic job on our architectural plans for our new single story kitchen extension in Brentwood. They gained us approval from the council and also provided the structural engineering for the project. We used their recommended builder who so far, we cannot fault one bit. Thanks again and highly recommend.
iansalsbury
10:54 24 Jan 25
The Kirkwood team were a pleasure to work with and have in our house. What can be a stressful time was made a lot easier by a team who build with quality, communicate clearly, and address and action any questions you raise....however small or large.We now have an amazing extension, and would be happy to use the team again.
Natalie Moore
12:29 23 Jan 25
Jamie and team are always helpful and very knowledgeable. Work on our kitchen extension carried out professionally and to high standard from design to build completion. A fantastic job, and very pleased. Many thanks
Kelly Pye
08:27 22 Jan 25
Jamie has provided lots of advice on house improvements including different options for extending as well as the possibility of a loft conversion. He responds quickly to queries and is full of knowledge! I wouldn’t hesitate to recommend him
Boris
19:35 12 Nov 23
Kirkwood Design and Build Builders, Wickford did a fantastic job on our extension in Billericay. They helped with planning permission, design, and build. Professional company through and through. Given that we haven't done such a large project before, we were a bit nervous and had a lot of questions. Jamie and his team from Kirkwood Design and Build Builders was good putting us at ease and now that we are fully complete with all our work, we further appreciate how professional this company is. Would highly recommend.
Holly Luckin
09:29 11 Nov 23
Nothing was to much hassle and Jamie is lovely!
john rocke
11:33 09 Nov 23
Great company and very professional. Nothing was a problem, very helpful and will definitely use them again. Have already given their details to a friend of mine.
Dave Lynch
19:32 08 Nov 23
Work carried out to a very high standard, very pleased with the results.
Sharon Gormer
13:06 07 Nov 23
Very professional company, helpful and friendly staff.
Aaron Tutton
11:15 07 Nov 23
Great builders, very professional and perfectionists! Thank you for such an amazing job
Olly Tait
13:28 21 Apr 23
Jamie and his team were so profesional from start to finish and made the job a joy to watch our dream come together.Very knowledgeable and contactable throughout the process.Couldn't ask for a better outcome and value for money.Will definitely be recommending and 100% will use again!5 star!!!
Sandie
20:03 20 Jan 23
I highly recommend the Kirkwood team! Exceptional workmanship, clear communication, Jamie & his team have provided the utmost as a polite & professional team! Very satisfied customer, looking forward to planning our loft conversion this year with you guys! Many thanks!
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frequently asked question

Please complete an enquiry form and submit your details. We will call you within 1 working day. If we can get through we will email you instead.

We are based in Wickford but we cover the whole of Essex and some part of London. 

Prices start at £1,195.00 and go up to £2,995.00

Permitted development for house extensions allows homeowners to build specific types of extensions without needing planning permission, provided they meet government-defined size and location criteria. As part of our architectural design service in Essex, we ensure your extension complies with these regulations. Additionally, we assist in obtaining a certificate of lawfulness, giving you legal confirmation that your project falls within permitted development rights

Get in contact with usb either calling, emailing, requesting a callback or completing an enquiry form. We are very quick at responding to enquiries.

Use ours is the short answer. We don’t have many as they are hard to come by, but the ones we do, won’t let you down.

Always the architect first if you want sound advice on what steps to take first. Kirkwood will advise on build costs in Essex as part of our service.

A certificate of lawfulness (COL) for a house extension is an official document that verifies the legality of a proposed or existing extension. It is also referred to as a lawful development certificate (LDC).

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