Principal works in the construction industry
According to approved document L of the building regulations, the term 'principal works' means:
| ...the work necessary to achieve the client's purposes in extending the building and/or increasing the installed capacity of any fixed building services. The value of the principal works is the basis for determining a reasonable provision of consequential improvements. |
Where, fixed building services are internal or external lighting systems (not emergency escape lighting or specialist process lighting), fixed systems for heating, domestic hot water, air conditioning or mechanical ventilation, or any combination of those systems.
And, consequential improvements are efficiency improvements consequential to changes to a building, required by regulation 28 of the Building Regulations to make the whole building comply with Part L of the Building Regulations.
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