Flat Roof Insulation Condensation

These roofs have similar moisture condensation performance as the compact insulated roofs discussed just below.

Flat roof insulation condensation. There are two forms of flat roof construction which can reduce the risk of condensation forming. However in many situations the insulation may need to be primarily or entirely below the flat roof membrane and between the roof joists if so what are the best options. Thick thermal insulation techniques often account for almost 70 of the problems of condensation in roofs. Usually this problem stems from either poor workmanship in installing the roof or insulation insufficient ventilation or excess moisture in the building.

However doing so increases the risk of condensation forming on the elements not surrounded by insulation such as cold roof decks. In the case of a flat roof insulation is usually in the form of either a rigid board above the deck or a fibrous quilt immediately above the ceiling depending on the type of roof construction. Compact insulated roofs with no roof cavity space. The designer therefore needs to consider the amount of insulation required to control both heat loss and condensation.

Cold flat roof insulation. Flat roof design guide. A flat roof should be designed to minimise condensation and a condensation risk analysis should be undertaken taking into account positioning of insulating materials vapour control layers ventilation thermal insulation and the choice of materials. Warm flat roof insulation.

Unvented flat roofs a technical discussion flat roofs have often been built with the insulation all on top of the vapor closed drainage plane as this avoids dew point condensation issues inboard of the roofing. This may help with condensation but causes such a loss of heat that it has been banned in scotland. The cold deck solution. Roof condensation occurs when moisture becomes trapped between the roof and the insulation.

Research has been able to show that lofts with very thick layers of thermal insulation materials are inevitably likely to exhibit condensation in roofs. The warm flat roof construction above will be much more cost effective and won t impact the living space below as the ceiling won t need dropping to add the roof insulation. Lots of traditional flat roofs are of the cold roof construction type. If this problem is not caught early it can be a.

The warm flat roof will solve the problem of condensation on the bottom of the roof decking however it will still be worth reducing the amount of humidity in the rooms. Add a preinstalled membrane to absorb and release the condensation as it forms with the natural weather cycle. This means there is a vapour control layer in the ceiling and cross ventilation at the eaves or the top of the walls. We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof.