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Low-energy design · BREEAM · Passivhaus principles · Part L and Part O
A building that costs less to run is worth more. We can prove it.
Our director is a RIBA chartered architect who is also a BREEAM Advisory Professional, qualified for both design and site. On BRE's public register she is the only architect listed as a BREEAM Advisory Professional with an Essex address (checked 12 September 2026). It means the energy, water and ecology decisions on your project are made by the person drawing it, from the first sketch, and measured against the standard the industry actually uses rather than a brochure word.
For homes
Fabric first. Then, and only then, the kit.
Extensions, lofts, whole-house retrofits and new houses.
The cheapest kilowatt is the one you never need. So before anyone talks about a heat pump, we look at walls, roof, floor, windows and draughts: where the heat actually goes in your house, and what it costs to stop it. Then we size the plant to the house you'll have, not the one you've got.
Extensions that don't leak
New rooms built to today's Part L, and junctions with the old house detailed so the extension isn't the cold end of the home. Overheating checked under Part O before big glazing is drawn, not after it's built.
Retrofit, in the right order
Insulation, airtightness, ventilation, glazing, then heating and generation, sequenced so each step makes the next one cheaper, and phased around how you live. Grants and funding flagged where they apply.
Heat pumps and solar that earn their cost
We design for them where the house can use them (as at Woodside View, a new house drawn around an air-source heat pump and a south-facing solar roof) and we say so plainly where it can't.
Reuse before rebuild
The greenest building is usually the one already standing. Converting a garage, splitting a house, extending rather than moving: lower carbon, lower cost, and often a faster planning route. It's the thinking behind most of our case studies.
Materials that last
Chosen for durability, health and what happens at the end of their life, not for a label. We keep up with the field (low-carbon insulation, timber systems, recyclable finishes) so you don't have to.
Designed to Passivhaus principles
For a new house or a deep retrofit we design to Passivhaus principles: a very well insulated and airtight envelope, triple glazing, heat-recovery ventilation, and the orientation and form that make those sums work, modelled from the first sketch rather than added at the end. The Passivhaus label itself is a certified standard, with its own certified designer and independent certifier; if the certificate matters to you, we bring them onto the team from the start. Most clients want the running costs and the comfort more than the plaque, and those don't need it.
For developers and commercial clients
BREEAM from the first sketch, not the last week.
Where a scheme needs a BREEAM rating (a council condition, a funder's requirement, a commercial or mixed-use building), the expensive way is to design it, then hire an assessor to tell you what you missed. The cheap way is to have the BREEAM Advisory Professional draw it. Credits are won in the layout, the orientation, the fabric and the specification, and those are decided in the first weeks.
We set the target rating with you, map the credits that are cheap to win and the ones to leave, coordinate the energy, ecology and water consultants, and carry the evidence through design and construction stages. On smaller housing schemes the same discipline covers Part L and Part O compliance, SAP and water calculations, and the surface-water and ecology conditions that stop a permission being implemented.
The conditions nobody budgets for
Water, drainage, trees, biodiversity, the Forest.
A permission in Essex or East London now arrives with environmental conditions attached, and each one is a document the council must approve before you start. We've discharged them on our own projects and we draft them as part of the design, not as an afterthought.
Surface-water drainage and water use
Drainage strategies to the council's satisfaction and the water-consumption calculations new homes must pass, both done for the three new houses at North Weald.
Trees
Arboricultural surveys and protection plans coordinated so the scheme respects the trees the council cares about and the builder knows where the fence goes.
Biodiversity net gain
Now a legal requirement on most planning permissions. We know when it applies, when a scheme is exempt, and how to evidence it: the ecology and BNG reports on our Maulden project were part of the application, not a surprise after it.
Epping Forest Special Area of Conservation
New homes within the Forest's zone of influence carry air-quality and visitor-pressure mitigation. It's a cost and a timetable item, and it belongs in the feasibility. See our Epping page.
Credentials
Why the qualification matters.
Dandi Passerini qualified as a chartered architect in 2013 and holds the BREEAM Advisory Professional qualification for both the design and the site stages of a project: the BRE-examined standard for steering a building to a sustainability rating from the outset. Before founding DZP Studio she worked in the teams at Heatherwick Studio, Grimshaw and AECOM, on buildings where energy, materials and environmental performance were the brief, not a footnote.
In plain terms: the person who draws your project is the person qualified to make it perform, and to tell you, before you spend, which measures will pay you back and which won't. The qualification is on BRE's public GreenBookLive register, where anyone can check it; at the time of writing, hers is the only listing at an architects' practice with an Essex address.
Start with your address
What would make your house cheaper to run, and would it pay back?
The Property Insight Report includes the energy picture for any address, the EPC band today and its potential, alongside the planning and value data. £149, read by a chartered architect before it reaches you, then 30 minutes with the architect who can turn the potential into a plan.
Questions
Asked about energy and BREEAM.
What is a BREEAM Advisory Professional?
BREEAM is the UK's long-established method for measuring how sustainable a building is: energy, water, materials, ecology, health and more. A BREEAM Advisory Professional is someone trained and examined by BRE to steer a design towards a target rating from the first sketch, rather than trying to retrofit points at the end. Our director holds the AP qualification for both design and site stages.
Does my extension need to meet BREEAM?
No. BREEAM applies to larger and commercial projects, and to developments where a council or funder asks for a rating. What a home extension must meet is the Building Regulations: Part L for energy and Part O for overheating. The BREEAM way of thinking still helps: it's how we decide where your money does the most good, whether that's insulation, glazing, a heat pump, or nothing more than orientation.
Is a heat pump worth it for my house?
Sometimes. A heat pump works well in a house that is insulated and airtight enough to be heated at low temperatures, and badly in one that isn't, which is why we look at the fabric first and the plant second. We'll tell you honestly whether your house is ready, what it would take to make it ready, and what grants apply.
Can you design a Passivhaus?
We design to Passivhaus principles, and we model the fabric, airtightness and ventilation so a new house performs close to that standard. Calling a house a Passivhaus is a different thing: it is a certified standard, with a certified designer and an independent certifier, and we don't offer the certificate ourselves. If you want it, we bring the certifier in from the start and design alongside them. If you want the performance, that is what we do.
Get in touch
Tell us about the project.
Whether it is a first conversation or a scheme someone else has already started, we are happy to hear where you have got to.
- Emailinfo@dzpstudio.co.uk
- Phone07508 382 877
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