Passivhaus Affiliate

Standard Members

Octavo Ltd



OKX Architecture


Based in Hereford, OKX Architecture is a market town practice keen to promote and introduce ecological and energy efficient design solutions to the wider community. The practice has experience in a broad range of sectors including commercial, retail and domestic, for business, small housing developers and many private clients, taking projects from inception to completion. Over the years the practice has also specialised in community buildings, working closely with registered charities and funding bodies. The practice undertakes the majority of projects throughout the Welsh Marches and the surrounding counties.

Optimum Architecture Ltd

Nr Colchester

Optimum Architecture was founded by Stuart Davis MCIAT, Certified Passivhaus Designer. We offer our services to suited clients to utilise our skills, experience and passion to design and realise a high quality, low energy project, either residential or commercial. Our experience enables us to provide our clients with designs that fulfil their requirements whilst achieving high quality architectural solutions. The Fabric First approach will achieve a premium standard of construction, superb comfort and low running costs. If you have a project that would benefit from our service then we would be pleased to discuss your requirements with you.