Bespoke Design & Planning

Over 12 Years of Experience

Free Consultation & Itemised Quotes

Full Cost Transparency & Project Management

Insurance Backed Warranty

Price Match for
Like-For-Likes Quotes

Being one of the most popular and family-friendly towns, Harrow boasts of every imaginable comfort, convenience, and amenity. And homeowners in Harrow are rightfully proud of their enviable addresses.

But with expanding families and changing lifestyles, even the best homes can feel cramped and uncomfortable. This is where home extensions come in.

Home extensions provide the simple but effective solution of upsizing your home at a fraction of the cost or inconvenience associated with moving houses.

Best of all, with the right design, and expert help, home extensions not only add space and comfort to your home, but also increase the value of your property by up to 20%!

A house extension is an opportunity for homeowners to design and create a piece of their home through bespoke extensions that add considerable space and value to a home.

When done right, home extensions in Harrow have the potential to transform the original property by creating uniquely designed rooms that are the perfect blend of beauty and functionality.

Home extensions are generally classified into different types based on the area of the property on which they are built. As such, home extensions in Harrow may be categorised into:

Rear extensions

Built on the rear of a property, rear extensions are immensely popular among homeowners due to the incredible versatility they offer in their design and use. Rear extensions are considered to be ideal for creating kitchen extensions, guest rooms, or even office pods.

Side return extensions

These extensions utilise the area that runs along the side of a property as well as a portion of the rear area. They are valued by property owners as they do not take up too much of valuable garden space. Side return extensions help to create beautiful indoor-outdoor connections that are a much-desired feature of modern dining rooms.

 

Wrap around extensions

Wrap around extensions are essentially a combination of rear and side extensions that create an L-shaped structure that ‘wraps’ around the property. Due to the immense width and depth they create, these extensions are perfect for designing multiple rooms, large kitchen-diners, or even open floor layouts.

Multi-storey extensions

Though more complex than single storey extensions, two storey extensions add incredible floor space to a home. These extensions are also viewed as being extremely cost-effective as they effectively double the square footage of the extension without doubling the roofing and excavation costs. Multi storey extensions may be used to design additional bedrooms, bathrooms, or even high-ceilinged living spaces.

The need for planning permission depends largely on the design and dimensions of the proposed extension. This is because extensions that fall under permitted developments do not require planning permission.

However, the criteria of permitted developments only allow extensions which meet specific size and height limitations. This includes a maximum height of 4m for single-storey extensions, and a maximum width of 50% of the original house for side extensions.

It is also important to remember that extensions on properties listed in conservation areas will invariably require planning permission irrespective of their dimensions.

The process of applying for and securing planning permission can take up to eight weeks and requires a comprehensive application detailing the proposed extension.

Homeowners must also apply for building regulations approval, and secure party wall agreements, to ensure that every aspect of the extension build complies with building guidelines and regulations.

Good Design and Build oversees this entire process for all our clients. This includes surveying the location, preparing architectural designs, coordinating with the local authority, and securing the requisite planning permission and building regulations approval.

With its beautiful homes and rich culture, Harrow is serious about its architecture.

Extensions constructed here must therefore aim to seamlessly combine with the original structure while maintaining its beauty and integrity. As such, home extensions in Harrow frequently feature these extension designs:

Kitchen extensions-

Invariably the most popular extension design, kitchen extensions are well-worth the investment as they help convert small, dark kitchen-diners into bright, spacious and inviting rooms that are perfect for hosting intimate family dinners as well as large celebrations.

With the addition of the latest fittings, they can be well-suited for modern homes and lifestyles.

Loft conversions-

Loft conversions work well to convert awkward and ill-used loft spaces into functional and elegant additional floor space. Loft conversions are often utilised to create extra rooms, bathrooms or even office nooks and playrooms.

Garage conversions-

Garages that are normally used as storage areas can be converted into valuable additional living space by incorporating the garage space with the interior layout of the property. This space can then be designed into a home office, guest room, playroom, or even a utility room.

Refurbishments-

For homeowners that do not wish to extensively extend, it is still possible to transform the existing space via refurbishments. This may involve remodelling the space to change the layout, creating open floor plans, and increasing the natural light that enters into the room through the addition of well-placed windows. All of this enables the creation of brighter and more spacious areas that better fit in to your lifestyle.

The cost of a home extension in Harrow can range from £35,000 to £135,000. This is because the cost of a home extension is dependent upon a multitude of factors. Some of these include:

  • The size of the extension
  • The design/complexity of the extension
  • Location
  • Groundwork
  • Building materials
  • Fittings and fixtures
  • Specialists’ fees

Good Design and Build offer free, no-obligations consultations and quotations for proposed extensions. This allows homeowners to design their dream extensions within their specific budgets.

Quite simply, Good Design and Build are the best of the best.

Being the foremost extension specialists in London, we specialise in creating beautiful bespoke extensions that are a true testament to our skill, passion, and professionalism. We pride ourselves in designing and creating the ultimate extensions that optimise the beauty, design, comfort, and functionality of your home.

Our exceptional team of surveyors, architects, builders, technicians, and project managers provide complete project management of the entire extension process from start to finish. This allows our clients to enjoy the incredible extensions created worry-free.

Don't move. Extend in style

We can save you the hassle that comes with moving not to mention the heavy stamp duty! Adding an extra loft bedroom or enlarging the living kitchen dining space on ground floor is an economical way of transforming your home to suit growing needs. The projects can range from £40-100K depending on your requirements and can be completed within 8-16 weeks.

Build a Quote

How we deliver projects

Our process is simple and divided into two distinct phases with separate contracts: Design and Build. As a client you only commit to one phase at a time depending on what stage of the process you are in. Each phase consists of three stages as described below.

1. Design

This is the kick-off point for your project. We carry out a complete architectural measured survey of the property. This allows us to create accurate CAD design drawings. This is followed by a design meeting to start discussing your ideas in more detail.

2. Planning

At this stage we finalise the designs with you and start preparing planning applications as needed. We place a high priority on ensuring that plans, designs and schedules are all based on a thorough and detailed understanding of planning guidelines. We co-ordinate with local authorities until the decision is made, and the planning approval is secured.

3. Technical

Once the planning consent is secured, we translate the design drawings into more detailed technical drawings for the purposes of building control and construction. This also includes specifications and structural calculations. At this stage, we will also submit to you our ‘no obligation’ quote for the build phase.

4. Pre-build

90% of our clients decide to stick with us after the design phase is completed. Once the build contract is signed, we kick off the process by making sure all the pre-build processes are complete. These include assistance with party wall agreements, Thames Water build over agreement, submitting building control application, and preparing method statements etc as needed. This stage ends with a pre-start meeting with your foreman before the actual build begins.

5. Build

One of our foremen will be dedicated to your project and will be on-site to manage everyday works. Our project managers will be overseeing the works to make sure they are completed to high standards, within your budget and on time. Throughout the process we will keep you updated with the progress and coordinate the works with third parties such as kitchen or flooring suppliers. We will also advise and guide you to choose any suppliers if needed.

6. Handover

As the build draws to finish, we will help to iron out any ‘snags’ to make sure everything is completed to your satisfaction. We will put together all necessary certificates such as gas, electricity and building control completion along with warranties for glazing, boiler etc. At the final completion meeting, we will hand you these documents, together with the keys to your house. Needless to say, you can contact us any time after this, if you want us to look at something.

This is the kick-off point for your project. We carry out a complete architectural measured survey of the property. This allows us to create accurate CAD design drawings. This is followed by a design meeting to start discussing your ideas in more detail.

At this stage we finalise the designs with you and start preparing planning applications as needed. We place a high priority on ensuring that plans, designs and schedules are all based on a thorough and detailed understanding of planning guidelines. We co-ordinate with local authorities until the decision is made, and the planning approval is secured.

Once the planning consent is secured, we translate the design drawings into more detailed technical drawings for the purposes of building control and construction. This also includes specifications and structural calculations. At this stage, we will also submit to you our ‘no obligation’ quote for the build phase.

90% of our clients decide to stick with us after the design phase is completed. Once the build contract is signed, we kick off the process by making sure all the pre-build processes are complete. These include assistance with party wall agreements, Thames Water build over agreement, submitting building control application, and preparing method statements etc as needed. This stage ends with a pre-start meeting with your foreman before the actual build begins.

One of our foremen will be dedicated to your project and will be on-site to manage everyday works. Our project managers will be overseeing the works to make sure they are completed to high standards, within your budget and on time. Throughout the process we will keep you updated with the progress and coordinate the works with third parties such as kitchen or flooring suppliers. We will also advise and guide you to choose any suppliers if needed.

As the build draws to finish, we will help to iron out any ‘snags’ to make sure everything is completed to your satisfaction. We will put together all necessary certificates such as gas, electricity and building control completion along with warranties for glazing, boiler etc. At the final completion meeting, we will hand you these documents, together with the keys to your house. Needless to say, you can contact us any time after this, if you want us to look at something.

Featured Projects

Interior View - Sellons Ave Project

Harlesden

Sellons Ave NW10 4HJ

The project included creating a master bedroom in the loft with an adjoining terrace.

Learn more

Fulham

Orbain Road SW6 7JZ

This project was completed in 2023 and the approximate budget was £101,000.

Learn more
Kitchen Extension in East Sheen

Lambeth

Hetherington Road SW4

We completed this stunning project for our client Angus in Lambeth.

Learn more

Teddington

Station Road SW4 7PA

We completed this exciting project for our clients on Station Road, a quaint residential area in the heart of Teddington.

Learn more

Leyton

Windsor Road E10

We completed this kitchen extension on Windsor Road, a charming residential street nestled in the heart of Leyton.

Learn more

What Our Clients Say

Close

Build a Quote!

Let's get started with building your own bespoke quote for your dream extension. Tell us as much in detail as possible to get most accurate price.

Get Started

Build a Quote!

Let's get started with building your own bespoke quote for your dream extension. Tell us as much in detail as possible to get most accurate price.

Get Started