Piers Sadler Consulting is now DeltaQ


A new name for our growing businessPiers Sadler Consulting changed its name to DeltaQ on 25 May 2022. The new name reflects our recent growth and our ambition to become a brand associated with excellence in Passivhaus project delivery and policy advice.

The name change and website launch has been a long time coming because it has been developing alongside growth in our workload, recruitment and development of systems to support the growth. As Delta Q we aim to provide an expert professional service to make Passivhaus buildings a reality at scale.


Δ denotes change or difference
Q in building physics denotes energy


ΔQ means difference in energy, which is shorthand for Passivhaus 😉