Bespoke Design & Planning

Over 12 Years of Experience

Free Consultation & Itemised Quotes

Full Cost Transparency & Project Management

Insurance Backed Warranty

Your property is once in an era kind

Mansion blocks were the Victorian answer to affordable, yet comfortable housing in London. Apart from their iconic charm, they have the potential to become more when you feel like you have less. If you own a mansion block penthouse, you should be proud of your property. The character of period properties is non-replicable and unique to their time. So, simply take advantage of mansion block loft conversions that can afford you with more space when you need it. Did you know that your mansion block top floor flat has plenty of hidden space in the roof? Bathrooms, bedrooms, libraries, and roof terraces are all possible additions for mansion flats.

We are Victorian home renovation experts. Period homes are our passion. We know that most period home-owners are attached to their property but often leave because they need more space for a growing family. You don’t have to move; you can always expand the floor area by discovering the hidden loft space. If you want confirmation whether your property meets the right criteria for an attic conversion or find the legal paperwork too daunting, we solve both for free! Make use of our free consultation and site survey. When we take on a project, we also complete legal requirements on behalf of the client.

Good Design & Build’s work is bespoke. Everyone has different needs, and every property must be considered unique living spaces. Our architects and engineers draw up designs that reflect your life and home. You are free to opt-out of the project if you are not happy with our designs. We always prepare contracts for two phases. You also receive full project management from the beginning to the end. We also allow for minor changes when you change your mind.

If your property is listed or is in a conservation area, you need planning permission. We apply on your behalf as our success rate is one of the highest. A leasehold property needs a freehold to the loft or attic above. If the freehold is shared, and you don’t own it, the freehold of the loft needs to be purchased. If a roof terrace is on your mind, there’s no need for planning permission, but you need to inform your neighbours. The same applies to party wall agreements. Semi-detached home-owners need to inform neighbours of planned conversions.

You may be living in an area or street deemed by your local authority as historically or architecturally significant. It is called a conservation area. The good news is, properties in such areas are higher in value. However, when it comes to loft conversions, you need to submit a full planning permission application for the proposed project. Once we make sure that your home is technically viable for conversion, we submit these applications on your behalf.

Living in a listed building requires planning permission for conversion projects. Any building with considerable historical, cultural, and architectural significance gets placed in the National Heritage List for England. There are around 500,000 listed buildings in England. By consulting this list, you will know whether your home is listed. Being listed doesn’t prevent change. Your proposal must contain a description of the property, its heritage, and the contribution it makes. You should also submit clear plans for proposed changes and how you will address all issues resulting from it. Your local planning authority will also request a Heritage Impact Assessment. All this work may sound too complicated to you, but not to us. We coordinate with local authorities with carefully prepared plans, designs, and information to secure permission for you.

If you feel like you have to move out of your beautiful mansion block property because you need a bit more space, we can change your mind with our loft extension techniques. So, you can stay and enjoy your home for longer.

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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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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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