Embarking on building works for your home is an exciting step, but it can feel overwhelming, especially if it’s your first time.
At Transition by Design, we are here to support you through every step and guide you through tough decisions using our expertise and experience. This guide explains the process step by step, so you know what to expect when working with us as we assist you through the process. It also shows how our approach ensures you can trust your project is well‑planned, cost‑effective, and future‑proof.
Why Choose Transition by Design?
We are an award‑winning, RIBA (Royal Institute of British Architects) chartered architecture workers’ co-operative specialising in ecological design, extensions, and low‑energy retrofit for homes. We are more than just architects, we are committed to shaping homes that support people and the planet. We focus on how the building performs for you.
- 15 Years of Expertise: We specialise in ecological, regenerative design and “low-energy retrofits”. We are Architects, Passivhaus Designers, and Retrofit Coordinators to deliver healthier, more comfortable, and more sustainable homes.
- A Proven Track Record: We have a strong track record of planning approvals and have successfully completed more than 20 domestic retrofit and extension projects, including listed buildings and properties in conservation areas.
- A Personal Approach: As a workers’ co-operative, we are driven by our values. We listen closely to understand your needs, tailor every detail and guide you through a process to transform your home. We are all about collaboration. Clients choose us not just for our design excellence and sustainability credentials, but for our approachable and transparent partnership.
- Our Promise: Together, we build homes that stand the test of time, are beautiful, resilient, and work in harmony with the environment and your lifestyle.
Click here to know more about what we can do for you and explore our portfolio for further details.
What is Retrofit?
You’ll hear us use the word Retrofit often. Simply put, retrofit means upgrading an existing building to improve its performance.
For homes, this usually involves adding insulation, improving ventilation, replacing windows, and upgrading heating systems. The aim is to make your home:
- Healthier to live in – Warmer in winter. Cooler in Summer. No more damp or cold spots.
- Cheaper to run – Drastically lower energy bills.
- Sustainable – Lower carbon emissions to help tackle climate change.
A key part of retrofit is setting energy targets and outcomes. These targets help measure how much energy use, carbon emissions, and running costs will be reduced. Using robust modelling tools like PHPP (Passive House Planning Package), we can compare different options and show you the likely savings. Outcomes are not just about numbers; they include improved comfort, better indoor air quality, and resilience against overheating.
Retrofit plans often align with industry benchmarks such as EnerPHit (the golden benchmark for retrofit, the link takes you to a project we completed, the second ever EnerPHit domestic project in the UK), LETI (London Energy Transformation Initiative guidance on net zero carbon buildings), and AECB (Association for Environment Conscious Building standards). These frameworks help ensure your project meets recognised levels of performance and quality.
We have also written an article that explains more about EnerPHit.
What Does the Journey Actually Look Like?
We follow the industry-standard RIBA stages. It is a framework widely used by architects and construction professionals across the UK to manage building projects in a clear and structured way. The building process is broken down into clear stages to help everyone understand the progress, and what to expect and when.
Here’s what happens at each stage, for both retrofit and extension projects:
Work Stage 1: Preparation and Brief
We meet with you to understand your goals, budget, and any issues (such as draughts, damp, or illogical layouts). We visit your home to assess its condition and prepare a clear project brief. This helps us understand your needs, and create a clear plan for what you want to achieve.
Deliverables:
– Project Brief
– Site Visit
Work Stage 2: Concept Design
We explore retrofit and extension options tailored to your home. Using PHPP energy modelling, we show how improvements could reduce energy bills and carbon emissions. For extensions, we test layouts and massing ideas to ensure new spaces feel integrated. This is the creative phase where your vision starts to take shape.
Deliverables:
– Sketch Design Options
– Whole House Plan with Retrofit Survey Report included
Work Stage 3: Developed Design
Once you are happy with the design, Wwe refine the chosen sketch design into fully scaled and digital CAD (computer-aided design) drawings including materials, and external finishes. For extensions, this includes room layouts, finishes, and how the new spaces connect to the old. Where relevant, we prepare and submit a planning application to the local authority.
Deliverables:
– Retrofit Specification
– Developed Design drawings
– Planning Submission Drawings and Reports (where applicable)
Work Stage 4: Technical Design
We prepare detailed drawings and specifications for contractors, coordinate with engineers and other consultants, and manage the tender process so builders can provide accurate quotes.
Deliverables:
– Technical drawings
– Specifications
– Tender Documents
Work Stage 5: Construction
Your contractor carries out the building works. We monitor progress, inspect the site, and resolve issues quickly. At completion, we check the quality of the work, arrange final tests (such as airtightness), and provide you with relevant documentation on your home for any future works
Deliverables:
– Construction Drawings and Documents
– Building Specification
– Site Inspections
– Contract Administration
Work Stage 6: Handover
When construction is finished, we check that everything meets the agreed standards and help you with information to settle into your new or improved home.
Here are the key documents you might come across in a project:
- Retrofit Survey – A detailed look at your home’s current condition, construction type, and issues like damp or overheating.
- Whole House Plan – A roadmap showing how retrofit and extension measures work together, their costs, and their impact on energy use and comfort.
- Sketch Designs – Early drawings showing layout and form options for your extension or retrofit.
- Planning Application Drawings and Documents – Detailed plans, elevations, and supporting information prepared and submitted to the local authority to secure approval for your extension or retrofit works.
- Retrofit Specification – A detailed set of instructions for contractors, covering materials, systems, and installation methods to ensure the work performs as intended.
- Construction Drawings and Specification – Fully detailed documents used by contractors to build accurately and to the required quality.
Frequently Asked Questions
Do I need planning permission?
Larger extensions usually require planning consent, while many retrofit measures (like insulation) may not. A planning application will not be required if the project fits within permitted development rights. We can advise and handle applications for you.
What is Passivhaus?
Passivhaus (sometimes written as Passive House) is an international gold standard for energy‑efficient buildings. It focuses on very high levels of insulation, airtightness, and controlled ventilation to create homes that need very little energy to heat or cool. Even if you don’t aim for full certification or even , using Passivhaus methods (like PHPP energy modelling) ensures retrofit measures are accurate, robust, and deliver real comfort and savings. It also ensures that and retrofit measures work synergistically with a low energy extension if planned.
What is permitted development?
Permitted development rights let you carry out certain home improvements, like small extensions or loft conversions, without a full planning application. These rights have limits and conditions, and don’t apply to all properties, such as listed buildings or homes in conservation areas. We’ll advise if your project qualifies.
What is contract administration?
Contract administration is the process of managing the building contract once construction begins. As your Architect, we act as your representative to ensure the contractor delivers the work to the agreed design, quality, and cost. This includes:
– Issuing instructions to the contractor if clarifications are needed.
– Checking progress against the programme.
– Assessing payment claims and certifying when payments are due.
– Monitoring quality and resolving issues on site.
– Managing changes fairly and transparently.
– Preparing a final certificate once the project is complete.
This role protects you as the client, ensuring the contractor is held to account and the project is delivered as agreed.
How long will it take?
Each project and stage has its own timeframe. Concept design may take a few weeks, planning approval two to three months, while construction can take several months depending on complexity. We provide guidance on the programme once appointed.
What if costs change?
Early budgets are estimates. As designs develop, the project costs can be refined and recommend a Quantity Surveyor for accuracy. We always keep you informed before changes affect our fees.
Can I live in the house during works?
Sometimes yes, but retrofit and extension works can be disruptive. We help plan phasing to minimise disruption and support in conversations with a builder around living in your home during works.
Ready to start your home’s transition?
The first step is a conversation. Click here to book a consultation and let’s discuss how we can make your home future-proof.
