This new guide from Hertfordshire Building Control uncovers essential guidance for specifying floor, roof, and wall elements in domestic extensions.
U-Value of Elements: A guide to the specification of
insulation materials in domestic extensions
This eBook, developed in collaboration with leading manufacturers in the insulation and concrete block industries, presents solutions meeting Approved Document L Volume 1 standards. It is backed by third-party accreditation for maximum U-Values attainment.
Hertfordshire Building Control provides a complete local authority statutory building control approval service across Hertfordshire.
Their team of qualified surveyors collaborates with builders, architects, and agents, ensuring that every building project achieves approval with the minimum of disruption.
Specifications should be constructed in accordance with the manufacturers’ technical guidance
The specifications listed in the guide should always be constructed in strict accordance with the respective manufacturers’ technical guidance.
Achieving optimal performance requires careful attention to insulation continuity and airtightness standards.
The indicative U-Values and insulation specifications provided are based on various assumptions and factors incorporated into manufacturers’ software, which impact thermal performance.
Ensure compliance with relevant national Building Regulations, including fire safety and condensation risk, and consult your Local Authority Building Control team for further advice if necessary.
