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An idyllic town that boasts of amazing architecture, a strong sense of community, and quick access to the city, Petts Wood has everything homeowners look for when seeking the perfect location to lay down some roots or start a family.

But even the best of homes (in the best of locations) can seem cramped and stuffy after a while. This is where loft conversions come in.

Loft conversions allow property owners to reimagine their home interiors, add space, and enhance the value of their homes; all without encroaching on the garden space of the property!

A loft conversion is, quite simply, the best way homeowners can transform the often ill-utilised or awkward loft corners into beautiful and valuable rooms that add space, value, and style to their homes. 

From beautiful bedrooms and spacious bathrooms to modern home offices and cosy study nooks, the design possibilities of loft conversions are virtually limitless; making them even more appealing to property owners who crave functional space.

Loft conversions are generally categorised based on the type of existing roof structure, and the structural changes involved. Some of the most popular loft conversions include:

Velux loft conversion

The simplest type of the conversion, Velux loft conversions are ideal for homes which have a roof height of at least 2.3m. This is because these loft conversions essentially involve the installation of roof windows (or Velux windows) into the pitch of the roof, without altering the structure of the roof. 

A staircase, additional insulation, and floor reinforcements then help convert this roof space into a quick, simple, and beautiful loft room. The bright and airy space created makes Velux loft conversions perfect for a guest bedroom, playroom, or even a spacious bathroom.

Rear dormer

Constructed on the rear part of the property, this type of loft conversion involves vertically extending the roof to create a box-like structure which provides additional headroom and floor space. 

Rear dormers are exceptionally popular in terraced homes as they are relatively simple and cost-effective conversions. They also help create the perfect additional bedroom or extra bathroom.

L-shaped dormer

Suitable for end-terraced and semi-detached properties, this type of loft conversion is essentially a combination of side and rear dormers to create a much larger space. This new space may be used to design multiple bedrooms, en-suites, or even playrooms and open-plan living areas.

The addition of a roof terrace or Juliet balcony helps to further optimise the design and create valuable outdoor space.

Mansard conversion

Though more complex to construct when compared to other loft conversions, mansard lofts are visually appealing structures that involve altering the existing roof to create a flat roof with a sloping wall. 

These conversions allow you to use the entire width of the property and may be used to design incredible living spaces within your home.

The cost of a loft conversion in Petts Wood can range from a modest £45,000 to a more extravagant £125,000. 

This is because the cost of a loft conversion is dependent on a large number of factors such as the design and dimensions of the loft conversion, the amount of structural work involved, as well as the fittings and insulation that need to be installed.

However, as most loft conversions increase the value of a property by up to 20%, the cost of a loft conversion is largely made up by the value that it adds to the property.

Reasons to Hire a Professional Team for your Loft Conversion Project

Though considered to be a relatively simple project, loft conversions have the potential to dramatically change the space and value of your home, and therefore must be managed with care and precision.

This is where the experts come in.

The expertise and experience of a professional team can help you to optimise the potential of the design and space while enabling you to avoid the many common mistakes that could prove costly in the long run.

While you may be concerned about the cost of hiring experts, the decision to design and build a loft conversion with professional help will drastically increase your chances of success by helping you to:

  • Plan and design the ideal loft conversion 
  • Avoid common errors and design flaws
  • Optimise the space to fit in your specific requirements or styles
  • Choose the right design that is suitable to the space
  • Understand and advise you on the feasibility of the plan by considering the area, cost and availability of building materials, environmental factors, and building guidelines
  • Oversee all aspects of the build including technical work and installations

Quite simply, an experienced and expert team can help make your dream loft conversion into an easy reality.

Being the primary loft conversion specialists in London, Good Design and Build are the de facto experts in loft constructions in the UK; with decades of experience and unmatched expertise in constructing high-quality conversions that epitomise beauty and functionality.

Our exceptional team comprises of surveyors, architects, builders, technicians, and project managers, enabling us to provide complete project management of the entire loft conversion process from start to finish. This allows our clients to enjoy their investment and the beautiful space created, stress-free.

We take pride in designing and building only the very best loft conversions which are ideally suited to the contemporary lifestyle, while our designs beautifully exemplify craftsmanship and skill to seamlessly integrate with your home while adding space and value to it.

Loft conversions are generally considered to be a cost-effective alternative to regular extensions. However, the cost of loft conversions is also dependent on a number of factors such as:

  • The design/ complexity of the conversion
  • Size of the conversion
  • Structural work involved
  • Location
  • Building materials
  • Fittings and fixtures
  • Insulation 
  • Specialists’ fees

Fortunately, Good Design and Build offer free consultations and quotations for proposed loft conversions. This allows homeowners to create their ideal conversions within their specific budgets.

One great benefit of loft conversions is that they can usually be constructed without the need of planning permission. However, this depends on the complexity of the conversion.

For a loft conversion to fall under permitted developments, it must meet with specific limitations regarding its size, design and structural alterations, the type of property on which the conversion is constructed, and where the property is listed. 

For example, a loft conversion which features a balcony or a conversion which is done on a property that is listed in a conservation area, will require planning permission.

Even those conversions that do not require planning permission will however, require building regulations approval. This ensures that the build complies with standard building guidelines.

A better question would be what is not?

Our exceptional team of architects, builders, technicians, and project managers, oversee every aspect of the conversion project, from start to finish, in order to create stunning loft rooms that add incredible space and value to your home.

This includes but is not limited to:

  • Initial survey of the property
  • Plan and design of the conversion
  • Securing requisite approvals and coordinating with the local council
  • Daily on-site management of the build
  • Contractual work, etc.

Our unmatched expertise, unparalleled passion, and utmost professionalism enable us to create the best, bespoke loft conversions that truly bring style, comfort, and even privacy to your home.

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.

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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.

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