Specifier Review
Building Regulations When Tackling New and Existing Flat Roofs

Building Regulations When Tackling New and Existing Flat Roofs

Building Regulations now require where feasible the extent of insulation within specified elements is upgraded as part of renovation works if the existing provisions are insufficient. Accordingly when constructing or replacing a cold flat roof, both ventilation and insulation qualities are normally reviewed.

Despite the growing popularity of converting to a warm roof, there are commonly situations where this is not possible.

This is often because the roof surface cannot be raised because of the proximity of external sills, openings, soil pipes etc.

Where a cold roof is the selected or default construction, there is an accompanying need to cross ventilate within it as well as ensuring any link from it to an external cavity wall complies with Building Regulations.

The Type RAV-FL is a flat roof ventilator from Cavity Trays of Yeovil. It is fitted by opening it like a book so one edge can be secured into the top of a timber upstand vertically battened off the wall surface.

The Type RAV-FL is then closed until its adjacent edge is against the external wall masonry to which it is then secured. The result creates a protected airflow route via which air can travel and cross ventilate the roof space.

The opposing roof edge incorporates a ventilator in the soffit or fascia. Cavity Trays offers a range of ventilator styles and ventilator colours from which to choose to achieve a balanced arrangement.


The Type RAV-FL provides the requisite airflow route to comply with Building Regulations

To arrest water gravitating within the external skin (above the Type RAV-FL) a preformed cavitray with an external flashing is located. The flashing is dressed down over the ventilator upper surface, ensuring protection against wind-driven rain.

One of a number of cavitrays offered to Cavity trays of Yeovil to prevent dampness gravitating below the roof line

Protecting the building envelope is the purpose of a wide range of products offered by Cavity Trays, and it is also the name of the latest technical manual released by the Company.

To secure your copy contact Cavity Trays of Yeovil . www.cavitytrays.com