Our qualifications and memberships reflect genuine assessment, ongoing compliance, and trusted standards across gas, heating, renewables, and commercial delivery.
Every accreditation Henman Dunn holds exists to protect you. From Gas Safe registration and TrustMark quality assurance to MCS certification for renewable installations, our credentials mean every job is carried out to the highest verified standard, with full documentation on completion.
We hold industry-leading certifications for both domestic and commercial work, every one earned through rigorous assessment and ongoing compliance.
The official UK register for gas engineers. We are registered for both domestic and commercial natural gas and LPG.
The Microgeneration Certification Scheme is the quality mark for small-scale renewable energy installations.
Government-endorsed quality scheme covering tradespeople across domestic properties.
Approved by Derbyshire County Council Trading Standards, which independently vets local businesses.
The Association of Plumbing & Heating Contractors runs a Licensed Member scheme for competent contractors.
The Oil Firing Technical Association certifies oil heating system installation and servicing.
The National Association of Professional Inspectors and Testers runs a competence scheme covering heating and electrical work.
The Contractors Health and Safety Assessment Scheme provides pre-qualification for health and safety compliance.
ConstructiLine membership verifies compliance, financial stability and technical capability.
Government-backed scheme ensuring high standards of installation and customer service in the home improvement sector.
The Renewable Energy Consumer Code protects households purchasing renewable energy.
SSIP-recognised health and safety pre-qualification scheme for contractors.
Certification logos are the property of their respective organisations. Copies available on request.