Parapet Wall Flat Roof Ventilation

Diagram below explains the build up.

Parapet wall flat roof ventilation.

The following images provide examples of flat roof details. This video is about making a transition form a flat roof to a parapet wall with taracotta clay caps. Flat roof detail masonry cavity wall flat roof insulation above and between joists. Where there is a parapet or an external wall abutment to the flat roof the fv250 ventilator can be used above a 150mm timber upstand battened off the wall by 25mm as shown below.

What is the best way of addressing the ventilation and weather barrier here. The 25mm batten space creates a clear airpath to the roof void below so reducing the possibility of condensation and mould growth. I have short 12 parapet walls surrounding a flat roof house in zone 2a. Venting in wood framed parapets.

Ventilated parapet detail cold roof installation of a typical ventilated parapet detail with the dryseal flat roofing system on a cold roof construction. If cavity is greater than 12 above roof insulation provide high low venting in each wall cavity. Parapet detail masonry cavity wall flat roof with parapet insulation. The parapet walls are connected to the attic i guess this would be termed ballon framed which is conditioned.

Flat roof detail examples. Treat these short parapet walls as part of the conditioned attic and cover.