Cold Deck Flat Roof Ventilation

A cold roof is where all of the insulation is placed either between and under or completely under the joists or deck.

Cold deck flat roof ventilation.

Guidance advice on warm cold. Flat roof ventilation allows for the circulation of air in the property particularly for warmer rooms in residential buildings. There are two types of flat roof systems warm and cold roofs which affect the positioning of the ventilation. You only need ventilation in a cold roof.

Ventilation is required for these roofs. Ventilation is not needed in a warm roof. The minimum requirements for cold roof ventilation are set out in bs 5250 control of condensation in buildings which takes into consideration span pitch and roof area. No insulation is on top.

When placed below the structural deck. Cold deck this is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof. What is flat roof ventilation. When thermal insulation is placed below the deck the ventilation must.

Ventilation is required to the underside of the deck. Introduction warm cold roofs this guidance offers guidance on the difference benefits between warm and cold roofs. This cold deck construction is considered problematic in the humid temperate climate of the uk where the effective ventilation of restricted roof voids may be impractical particularly in sheltered built up areas. Warm deck the type of insulation for this is usually of a rigid type and the thickness will vary depending on the manufacturer s specifications.

In a cold roof construction the sarnafil membrane is installed directly to the structural decking usually timber with firrings to fall. Ventilation is required for these roofs. A cold roof is the most common type of roof construction often taking the form of an uninhabited storage space.