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This exclusive postcode serves you well, and its world-class schools put it in an enviable catchment area. Open green spaces for leisure and activity are plenty in family-friendly Dulwich. So, why not make it your permanent home? If you are struggling to find more space in your home, then loft conversions Dulwich will solve your problem without needing to look elsewhere for space. Good Design & Build specialise in inspiring space solutions for Victorian and 1930s homes across London. Enhance your property value with more space, contemporary design, and energy efficiency. Make it attractive to future buyers at the same time.

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.

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A loft conversion is a popular solution for increasing the habitable floor area of a property, especially in urban areas like southeast London, where upsizing isn’t always affordable. It also extends the usable space of your home without the inconvenience of moving away. The process turns the underutilised attic of particularly Victorian and 1930s homes into functional living areas, such as bedrooms, bathrooms, home offices, playrooms, gyms, or even art studios. Usually, the roof structure gets modified to build upwards. The new space will have flooring, roofing, ceilings, windows, doors, and staircases.

Rooflight Conversion – also known as a Velux conversion is a type of loft conversion where roof windows or skylights get installed into the existing roof slope of a property’s loft space. These windows introduce natural light into the loft. It is particularly suitable for lofts that already have sufficient head height and don’t require major alterations to the roof structure.

Dormer Conversion – it extends the existing roof vertically, creating additional floor space and headroom within the loft. Dormers usually have a flat or pitched roof and can feature windows, providing more usable space than a roof light conversion. They are a common sight in residential areas in London.

Mansard Conversion – a mansard conversion involves changing an entire roof plane to create a generous space. It features a nearly flat roof with the back wall sloping inwards at an angle of 72 degrees. Mansard conversions often require planning permission due to the significant alterations made to the roof structure. They are suitable for most property types including terraced, semi-detached, and detached homes. 

Hip-to-Gable Conversion – suitable for properties with hipped roofs, it involves replacing the hip of the roof with a gable (a vertical wall). Hipped roofs can inhibit the usable floor area of a home, and this conversion type frees up more habitable space. Extension of the roofline creates additional interior space for a functional living area. 

L-shaped Conversion – two dormers get joined to double up space. One dormer, usually the bigger one, is positioned on the main roof, and the other, often a smaller one, sits on the rear outrigger. The outrigger is a significant feature in a Victorian or Edwardian home. This type of loft conversion maximises space, particularly for a mid-terrace property.

The cost of your loft conversion in Dulwich can vary depending on the type, size, and style. While the most cost-effective loft designs are Rooflight and Dormer, the other more substantial space creations can cost more. Our full cost transparency provides you with a clear idea about the budget. There are no hidden costs, and our itemised quote is free.

Room in the roof conversion (basic) –  £35,000

Dormer loft extension –  £50,000

Mansard extension – £60,000 – £65,000

Hip-to-gable extension –  £65,000

L-shaped extension – £65,000 – £75,000

Loft conversions aren’t just space-generating home improvements but also significant additions that increase property value. Elegant designs, space maximisation, and superior construction can give you a high ROI. Professional conversion specialists can seamlessly integrate modern living spaces into your home’s footprint to enhance aesthetic appeal and functionality. 

They are proficient in local building and planning regulations, so there’s no chance of later lawsuits that can undo hard work. And when it comes to conception, without a practical design with clever space utilisation, your loft conversion may never live up to your dreams or be the best your money can build. So, do not hesitate to turn to the right team that can do so much more for you than a DIY project.

We specialise in Victorian and 1930s property loft conversions across London, including the charming Dulwich. Design-centric, our projects are bespoke architectural feats. We have a team of architects, structural engineers, project managers, and builders who come together to create aesthetic spaces that harmonise with period architecture. Our designs focus on natural light, open-plan living, and modern comforts. We create 3D designs using the latest technology for a more intimate visualisation of your space.

We ensure our designs comply with local laws and even submit planning permission and building control applications on your behalf. Good Design & Build provides complete project management from start to finish. We also work with third-party suppliers to get you the best products your money can buy. Our completed works are a testament to our commitment to quality and innovation.

The type of loft conversion you choose and the size of your property are the two main factors that decide the cost of loft conversions. Certain property types and conversion designs require more work, while others do not. The more structural changes involved, the more it costs. Bespoke solutions can lower costs, and our design team is always willing to offer their expertise on cost-effective loft conversions unique to your property and needs.

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.

What Our Clients Say

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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