Smartly Designed House Extensions in Brentwood
Start your home extension way with top-end architectural plans, expert planning support, and access to vetted builders.
Brentwood's #1 house extension
architectural design firm
Brentwood's #1 house extension architectural design firm
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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.
We now have an amazing extension, and would be happy to use the team again.
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!!!
Single storey house extensions are one of the most popular choices for Brentwood homeowners. They’re a cost-effective way to add more living space and come with loads of design options. You might want to extend the kitchen, create an open-plan kitchen diner, add a utility room to free up space, or build a new office and shower room. The possibilities are endless. Most single storey extensions fall under permitted development, but that doesn’t mean you can skip the paperwork. Approval is still needed. Brentwood house extensions like these are what we specialise in. Share your ideas with us and we’ll guide you through what’s possible.
- Avoid costly build errors
- Access reliable builders
- Prevent council disputes
How a single storey extension can transform your home
A single storey extension can completely change how your home works and feels day to day. It’s without fail the best way to create a bigger kitchen. Everyone nowadays wants that open-plan kitchen diner design, and since the kitchen is nearly always at the rear of the property, it makes sense to extend there. Many Brentwood homeowners use this type of house extension to add a downstairs WC or create space for a utility room. As local Brentwood architects and experienced Essex architects, we’ve seen how the right kitchen design can make a huge difference. Brentwood house extensions like this can truly transform your home. Add large glass doors and roof lights, and you’ve got a home extension that’s Instagram-worthy.
For modern inspiration, take a look at our contemporary single storey extension guide.
Planning and build costs for single storey extensions in Brentwood
Knowing how much a single storey extension in Brentwood costs will help you decide whether the project is affordable, so we guide homeowners on build costs from the very beginning. We start with a Zoom call to discuss your requirements, then provide our architectural fees along with approximate build costs. A 3 metre house extension is one of the most common options, as it often falls under permitted development. That said, every project still requires proper plans and some form of approval, full planning permission is rarely needed, but a Certificate of Lawfulness should always be obtained before the build starts. As reliable Brentwood architects and trusted Essex architects, we guide you through the extension planning process, council fees, and expected timescales for Brentwood house extensions.
Learn more about permitted development
Why single storey extensions are a smart choice in Brentwood
Many homes in Brentwood are perfectly suited to a single storey extension, especially those with decent space to the rear or side. These houses are ideal for building an open-plan kitchen diner or a 3 metre house extension under permitted development. A well-designed home extension in Brentwood can completely transform how your ground floor feels. Brentwood house extensions are especially effective when designed around how you live day to day. Finding the right local architect for extension planning in Brentwood helps avoid costly build errors and disputes with the council. Skip the full Brentwood planning permission route where possible and speak to our team for advice.
Why choose Kirkwood for your house extension in Brentwood
Every member of our team genuinely cares about providing a 5-star level of service. It started with the founder of the company and has naturally attracted skilled professionals who share the same values. Our prices offer serious value, with competitive rates matched by top-end results. We’ve got a huge amount of experience working with councils across Essex, which really helps when it comes to gaining approvals and keeping things moving. From the start, we give advice on build costs and offer all the services needed for a smooth project. We don’t know many Brentwood architects who do that, but for more guidance, take a look at our article on Finding the right architect for your Brentwood home extension. We’re also very particular about the builders we recommend. They’ve got to be fairly priced, highly skilled, and dependable. When it comes to Brentwood house extensions, we only work with teams we trust.
Planning Permission & Permitted Development
We know Brentwood Borough Council very well. We assist with full planning applications to permitted development rights, we handle all the paperwork and approvals for your house extension.
Architectural Design & Extension Plans
As full-service Brentwood architects, we design to suit your build budget and avoid surprises later. Our extension plans cover layout ideas, building regulation drawings, and structural calculations all in one.
Build Costs & Trusted Builders
Before you spend anything on your Brentwood house extension, it’s important to understand all the costs, especially build cost. We arrange a Zoom call early on to explain what to expect and how it all adds up.
Popular types of house extensions in Brentwood
There’s no one size fits all when it comes to Brentwood house extensions. Everyone’s needs are different and that is where our lengthy experience as Brentwood architects comes into play. We’ve designed every type of house extension imaginable, from small 3 metre house extensions at the rear to large double storey extensions with loft conversions above. We advise on build costs, planning permission and all extension planning in Brentwood requirements. If you need permitted development rights, structural engineering calculations or building regulations drawings, we cover that too.
Single storey extension Brentwood
A single storey extension in Brentwood remains the most popular option for good reason. It’s a speedy build and cost-effective for adding a kitchen extension, home office, utility room, or even a downstairs WC. We’ve helped thousands of families transform their homes with single storey house extensions in Brentwood. Most of these fall under permitted development, but we still handle the paperwork to make sure everything is approved properly. If you’re wondering how much a house extension costs per metre squared, we can give you realistic figures early on and help you avoid unaffordable build costs. As trusted Brentwood architects, we guide you through every step, including building regulations and extension planning in Brentwood.
Double story extensions Brentwood
A double story extension in Brentwood is kind of like buying a new house without having to move. Built to the side or rear, double story extensions add serious square footage, often making room for an extended kitchen, open plan living area, utility room and an extra bedroom with en-suite. There are loads of designs a good Brentwood architect can create and we’ve worked on every type of double story house extension in Brentwood, including wrap around layouts and side return builds. These home extensions offer great value for money by using the same foundations and roof to create space over two floors. We help with everything from early house extension ideas to full extension planning in Brentwood. We make sure your double story extension meets building regulations and has the best chance of approval. If you’re wondering how much a house extension costs in Brentwood, we’ll guide you through realistic build costs and local planning advice.
Rear extensions Brentwood
Rear house extensions in Brentwood are one of the most common types of home extensions we design, especially for homes with a decent-sized garden. They’re ideal for creating a large open-plan kitchen diner and, if the house is over 8 metres wide, there’s often room to add a living room extension too. Since most kitchens are located at the back of the house, extending here just makes sense. Many of our Brentwood house extensions fall under permitted development rights, but we still prepare and submit all the necessary paperwork for approval. As experienced Brentwood architects, we design each house extension to suit your layout, while also bringing fresh architectural ideas you may not have considered. If you’re wondering how much a rear house extension costs in Brentwood, we’ll talk you through realistic build costs on your free initial consultation.
Not sure which roof style suits your project? Read our pitched roof vs flat roof extension guide to help you decide
Kitchen extensions Brentwood
A kitchen extension is one of the most requested types of Brentwood house extensions. Most homes have kitchens at the rear, making them perfect for single storey kitchen extensions that open up into the garden. With more people working from home, a lot more time is being spent in the kitchen, so maximising this space and creating a kitchen extension you actually enjoy being in is a worthwhile investment. That’s not just coming from us, it’s what we hear from our previous house extension customers in Brentwood. We have designed hundreds of kitchen extensions in Brentwood, often using wrap around or single storey rear extension layouts. As trusted Brentwood architects, we offer a five star service to every customer, making sure your design meets your house extension needs, complies with building regulations in Brentwood, and secures the right type of Brentwood council planning permission. We can guide you through kitchen extension costs in Brentwood and give honest advice tailored to your home and budget.
Loft conversions in Brentwood – Use every corner of your home wisely
A loft conversion is a smart way to add extra living space without extending the footprint of your home. In Brentwood, many properties such as detached and semi detached homes with pitched roofs are ideal for this type of home extension. As experienced Brentwood architects, we design all types of loft conversions including dormer, Velux, and full hip to gable conversions. We prepare your home extension plans, manage the application process, and submit everything to Brentwood Council under permitted development or full planning if needed. To find out how much a loft conversion costs in Brentwood, get in touch with our Essex architects today.
Do You Need Planning Permission?
Most Brentwood loft conversions fall under permitted development, but we still apply for a Certificate of Lawfulness.
How Much Does a Loft Conversion Cost?
Dormer loft conversions in Brentwood start at £45,000. We guide you on costs from the start.
Types of Loft Conversions in Brentwood
We design dormer, hip to gable, and Velux loft conversions in Brentwood to suit your layout and roof.
Garage conversions in Brentwood
Affordable extension
If you have a garage that is not being used properly, converting it could be one of the most affordable ways to add extra space. Most garages are not much use for parking these days, especially with the size of modern cars. A garage conversion in Brentwood transforms that wasted space into something practical, like a home office with a shower room, a snug, a gym, a spare bedroom, or a utility area to free up space in the kitchen.
Garage conversion costs
Most garage conversions in Brentwood fall under permitted development rights, so it is rare to need full planning permission, but it still depends on the property. If your home is in a conservation area or if the front of the garage is being extended forward, a different type of application may be required. We check all of this for you and deal with Brentwood Borough Council on your behalf. The build usually takes around four to six weeks, and garage conversion costs typically start at around £15,000, rising to £25,000 or more depending on the size and specification. An experienced Brentwood architect can prepare your garage conversion plans and submit them for approval if needed.
House extension planning in Brentwood
Planning a house extension in Brentwood doesn’t need to be complicated. For us, it’s a clear process that follows a series of steps we’ve been through many times before. It takes a strong understanding of Brentwood planning permission, permitted development rights, building regulations, build costs, and more. These are all things a skilled Brentwood architect should know inside out. We seek approval for all Brentwood house extensions, even for a 3 metre house extension that falls under permitted development, because every project needs some level of permission. Whether it’s a single storey extension or a larger double storey build, the process can still be straightforward when you work with the right team.
How much does a house extension cost in Brentwood?
One of the first things Brentwood homeowners want to know is how much a house extension costs, and rightly so. It’s important to know if it’s affordable before spending money on architectural plans. As experienced Brentwood architects, we help you understand build costs right from the start. Our process begins with a free Zoom consultation where we talk through your ideas and give you approximate build costs along with exact design fees. Whether you’re planning a 3 metre house extension under permitted development or a larger two storey extension, we’ll make sure you’ve got realistic figures before moving forward.
Cost per square metre for house extensions in Brentwood
On average, the cost of a house extension in Brentwood starts at around £1,900 per square metre. That would cover the main build, excluding finishes like decorating, flooring, and the kitchen. For a 3 metre single storey extension measuring 3 by 5 metres, expect to pay around £30,000 to £35,000 plus VAT. Add in things like a new kitchen, electric roof windows, or external lighting, and the overall cost will increase. These are all things we guide you through from the start to make sure your home extension in Brentwood fits your budget and goals.
What affects the price of a house extension?
Several things affect how much a house extension costs in Brentwood. Size is the biggest factor. Anything over 20m² tends to sit around £2,000 per m², but smaller extensions can sometimes push that rate up. The foundation type can also play a big role in costs—piled foundations for house extensions can add £10,000 or more, depending on the size of the job. As local Essex architects with extensive experience in extension planning in Brentwood, we help you understand all the variables so you’re not hit with any surprises.
Home extension cost calculator
If you’re still asking, “how much does an extension cost in Brentwood?” then use our free design cost calculator. It gives us the details we need to send you an estimate based on your extension type, location, and size. It doesn’t take five minutes to complete and helps us provide accurate build costs for house extensions in Brentwood. For detailed advice and a personalised quote, book your free call with one of our Brentwood architects today.
Ready to start your home extension in Brentwood?
If you’re planning a home extension in Brentwood, Kirkwood is here to help. The experienced team provides guidance through every stage, from architectural design to securing planning permission with Brentwood Borough Council. Whether it’s a loft conversion, garage conversion, or kitchen extension, designs are created to maximise space, comply with building regulations, and enhance the home.
Get in touch by emailing info@kirkwoodbuild.co.uk or phoning 01268 944233 to schedule a free consultation. Let’s turn your ideas into a well-designed, approved, and beautifully planned extension.
