AECB Design for Low-Energy Homes

A simpler path to a better-performing home

We help homeowners create healthier, more efficient spaces using the AECB low-energy design standard—a flexible, fabric-first approach rooted in building science.

Terrace House - EnerPHit retrofit

A Practical Standard for Real Homes

We use AECB design principles to help homeowners make meaningful improvements to energy use, comfort and air quality—without over-complication.
It’s based on the same science as Passivhaus, but tailored to fit real homes, real budgets, and the character of existing buildings.

Natural insulation materials used in low-energy retrofits: wood fibre, cork, hemp and recycled wool

What this means for your home

  • Energy Modelling: We use PHPP to understand your home’s performance and guide decisions

  • Airtightness Strategy: Careful detailing to reduce drafts and heat loss

  • Ventilation Design: Fresh air in, stale air out—without wasting energy

  • Fabric-first Upgrades: Natural, breathable materials that protect the building and those who live in it

  • Phased Planning: If needed, we can break the work into manageable stages

Which is Right for Your Project?

AECB Standard EnerPHit (Retrofit) Passivhaus (New Build)
Space Heating Demand ≤ 40 kWh/m²/yr ≤ 25 kWh/m²/yr ≤ 15 kWh/m²/yr
Airtightness ≤ 1.5 ach@50Pa ≤ 1.0 ach@50Pa ≤ 0.6 ach@50Pa
Primary Energy Demand ≤ 120 kWh/m²/yr ≤ 120 kWh/m²/yr ≤ 120 kWh/m²/yr
Certification Optional Required Required
Best For Upgrades to existing homes, phased retrofits Deep retrofit of existing homes High-performance new builds

Read more about EnerPHit or Passivhaus design

Want to understand what’s possible for your home?

We offer two ways to help you decide on the best way forward, depending on what you need clarity on.

A Retrofit Strategy focuses on energy performance and comfort. It helps define the right scope and sequence for a retrofit, so improvements work together and avoid unintended problems.

A Home Visit Appraisal looks more broadly at your project. It considers scope, constraints, and likely costs, helping you understand feasibility and make informed decisions early on.

Book a Call

Our latest articles.

Sustainable Architecture Blog
How To Insulate A Period London Home

Insulating your home has many benefits, not just for the environment but also for your wallet. Achieving appropriate levels of insulation with the right materials not only helps lower greenhouse gas emissions but also minimises heat loss and reduces overall energy consumption.

Insulating your home is a win-win situation for all. 

In this article, we will delve deep and discuss the importance of a holistic approach and best sustainable practices for both internal and external insulation.

Read More →
The Case For Daylight

Have you ever wondered how natural light can transform a space, bringing warmth and vitality into your home? Conversely, have you thought about the potential challenges it can create? Striking the right balance between embracing daylight and managing its drawbacks is essential in residential design.

Daylight has advantages and disadvantages. An outstanding design should consider both.

This article outlines the aspects to consider, giving tips and creative design solutions for drawing daylight in to your new or refurbished home.

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Mechanical Ventilation and Indoor Air Quality in London Homes

Good indoor air quality is essential for comfort, health and the long-term condition of a London home. Moisture, pollution and stale air build up quietly in older properties, especially when windows stay shut because of noise, privacy or security concerns. Mechanical ventilation with heat recovery provides a reliable solution. It delivers filtered fresh air, removes moisture before it becomes mould and recovers most of the heat you have already paid to generate. If you are planning a renovation or whole-house retrofit, integrating MVHR can create a home that feels cleaner, quieter and far more comfortable every day.

Read More →