Room in Roof

by | Apr 30, 2024 | Glossary, Last Articles | 0 comments

Understanding Room in Roofs: A Comprehensive Guide to Building Compliance and Energy Efficiency

In the world of construction and building compliance, the concept of ‘Room in Roofs’ (RIR) is gaining significant attention. This blog post aims to provide a comprehensive understanding of RIR, its implications in SAP calculations, and considerations for air tightness and thermal bridging.


A ‘Room in Roof’ is a living space that is situated within the roof of a building, typically seen in houses with pitched roofs. These rooms are often found in loft conversions and can provide additional living space without altering the building’s footprint. Other examples include dormer extensions and dormer bungalows or chalets.

RIR Implications in a SAP Calculation

The Standard Assessment Procedure (SAP) is the UK government’s recommended method for measuring the energy rating of residential dwellings. The presence of a RIR can significantly impact a building’s SAP calculation.

  1. Insulation: RIRs often have complex shapes and angles, making it challenging to insulate effectively. Poor insulation can lead to higher heat loss, negatively impacting the SAP rating.
  2. Ventilation: RIRs can sometimes have limited ventilation, leading to potential issues with damp and mould. This can also affect the SAP rating as good ventilation is essential for energy efficiency.

RIR Air Tightness Considerations

Air tightness is a critical factor in energy efficiency and building compliance. For RIRs, there are several key considerations:

  1. Sealing: All joints and gaps in the RIR should be adequately sealed to prevent air leakage. This includes the areas around windows, doors, and where the roof meets the walls.
  2. Ventilation: While it’s important to seal any leaks, adequate ventilation is also necessary to prevent condensation and damp. This balance between air tightness and ventilation is crucial in RIR design.

RIR Thermal Bridging Considerations

Thermal bridging occurs when heat is lost through a less insulated part of the building’s envelope, such as where the walls meet the roof in a RIR.

  1. Design: To minimise thermal bridging, the design of the RIR should ensure continuity of insulation at all junctions.
  2. Materials: Using thermally efficient materials can also help reduce the impact of thermal bridging.

In conclusion, ‘Room in Roofs’ present unique challenges and considerations in building compliance. However, with careful planning and execution, they can provide valuable, energy-efficient living spaces. At Building Compliance Testing Limited, we are equipped to navigate these complexities and ensure your building meets all necessary standards.

Stay tuned for more insights and updates in the world of building compliance!