Dripstop Introduction

Dripstop can be added to Box Profile 32/1000, Box Profile 34/1000 and Corrugated 13/3 sheets. It cannot be added to the tileform sheeting due to the shape of the profile. It is recommended to help the dripstop work that the roof pitch should be more than 10 degree pitch. 

Dripstop is an anticondensation felt membrane which can be applied to the reverse of our steel roofing sheets. Dripstop is a proven way of stopping sheets dripping with condensation in conditions of high humidity.

Condensation can occur when warm, moist air inside a building comes into contact with cold surfaces. This occurs on the underside of the roof in un-insulated single skin metal buildings during the winter. It can also occur on clear nights when the temperature of the roofs surface is lowered due to night sky radiation.

Condensation can run down the roof and collect on or within the fabric of the building where it could cause rust, rot, damage and may also drip from the roof.

Dripstop Diagram

Dripstop is a membrane designed to reduce damage from dripping or running condensation on metal roofs in buildings with moderate to high levels of humidity and low ventilation.

Dripstop controls condensation in an environment where you can get cyclical condensation occurring. It does not completely prevent condensation and feels damp when touched when working correctly. For dripstop to work correctly the building must be adequately ventilated for all the material to dry out between each cycle.

Dripstop membrane can be applied on the reverse of the sheeting, this creates a medium for trapping moisture in the specially designed pockets formed in the felt membrane.

Dripstop holds that moisture until conditions go back below the dew point and it is released back into the air in the form of normal humidity.


Dripstop is self-adhesive and is applied to the reverse of the sheet in the roll forming process. This means that when your sheets arrive, they will be ready to use without any tricky installation of installing the membrane.

The dripstop membrane absorbs and holds condensation until it can evaporate whilst insulating the sheeting and preventing drips from the underside of the roof, thus reducing the formation of condensation.

Dripstop can only be used in buildings with a guaranteed supply of airflow such as open sided or fronted buildings, i.e. agricultural barns or industrial units". If you are unsure whether your building has sufficient airflow please contact our helpful sales team who will be happy to assist you.

To order sheets with dripstop please contact our sales team on 01837 659901.