The Building Envelope Calculator allows you to see at a glance what impact your building envelope design decisions will have in passing Part L requirements.

This calculator is simple to use and only requires some basic details on the parameters of the building. From there information such as U-values and air permeability can be altered to see what the effect is on the overall % improvement of the building envelope in accordance with Part L.

The Building Envelope Calculator produces results for:

• Warehouses
• Supermarkets
• Schools
• Retail
• Hotels
• Office: Shallow Pan - Heated
• Office: Shallow Pan - Air Con
• Office: Deep Pan - Air Con

To learn more about how to use the tool, watch our instruction video or to begin using the tool click the "Launch The Building Envelope Calculator" button.

This example Building Envelope Calculation is based on Building Regulation ADL2A:2010. The amendments that can be made are indicative only for the external envelope. The enhancements for the Actual building over the 2010 Notional building with the same envelope areas including the same areas of rooflights. This calculation does not take account of solar gains, heating, cooling, lighting, etc.

In accordance with Approved Document L2A 2010, the whole building must be calculated for compliance using Simplified Building Energy Model (iSBEM) tool or similar, which takes in to consideration; solar gains, heating, cooling, lighting, etc. This calculation should only be used to establish the principles of enhancing the thermal elements of the building i.e. the overall performance of the external building envelope (including floor).

Notes & Requirements

• Opens in a new window
• Optimised for use in Internet Explorer 7 / 8 and FireFox 3.5 / 3.6
• Javascript must be enabled
• Recomended 1280 x 1024 screen resolution or higher
• Besure to bookmark this page to save registering again.
  

The Building Envelope Calculators is very powerful, yet easy to use:

• Step 1 - Building Details
  Enter some basic parameters about your building, such as size, number and size of any openings and percentage of rooflights.
• Step 2 - U-values and Thermal Bridging
  Alter U-values for the roof, wall and rooflights as per your requirements and select from 'Notional Building Psi-values' or 'Thermally Efficient' details.
• Step 3: Air permeability
  Set the desired air permeability rating. As a guide based on the floor area, use the following:
  10,000m² or above - air permeability 2.5m³/hr/m²
  3,000m² to 10,000m² - air permeability 4.0m³/hr/m²
  1000m² to 3000m² - air permeability 5.0m³/hr/m²
  Less than 1000m² - air permeability 8.0m³/hr/m²

Note: Lower air permeability rates are harder to achieve as the building decreases in size. This is because the smaller the building, the larger the ratio of building air space to areas where air leakage can occur ie. perimeter details and doors

Or want more information on how to improve your building envelope, contact our technical team on 01388 830 294

Alternativlly you can get in contact via email: technical@cagroup.ltd.uk

To learn more about Part L and CA Groups approach to Sustainability, Click here.