Nowadays we all want lots of natural lighting BUT the Building Regulations Part L1B require that areas of new glazing should account for no more than 25% of new floor area and for the modern Highly Glazed Extension that is not compliant with the Part L1B, EAC will carry out both a Notional and a Proposed Energy Assessment to ensure that the final project specification for insulation and heating elements are all considered to obtain a complaint Building Regulation application.

 

Although the SAP calculation is a complex process, the end product will provide far more flexibility and we will work with you to ensure that your design principles are not compromised.

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Building Regulation L1b Approved Document

 

SAP Calculations for Highly Glazed Extensions

 

Glazing and openings lose more heat than well insulated walls and roofs and this is why the Building Regulations set a 25% limit for glazing however, by upgrading construction elements, demonstrating additional energy saving appliances or the benefits of useful solar gains through the extra glazing, the negative impact of larger expanses of glass can be removed.

 

We can save you money

 

This process can enable the identification of options to upgrade the existing property if a renovation project is planned as we can advise you on cost effective options.

 

We will require the following to carry out a SAP calculation:

 

• Site address and post code

• Site plan to include a north direction point

• Scaled floor plans, building elevation and section drawings

• Construction details of floors, walls and external walls

• Details of windows and doors

• Details of the heating and hot water system

• Ventilation

• Lighting and any renewable technology used