Air Gap Siding

An air gap prevents hydrostatic pressure in the wall assembly lets gravity drain liquid moisture and water vapor to exit at ventilated terminations.

Air gap siding.

Air gap or air film 3 4 air space insulating properties. Click here to see an animation of the rain screen principle and other links to more details of this critical air space that helps walls to stay dry throughout canada. A 3 8 inch air gap i e. A predictable rainscreen air gap behind fiber cement sidings like james hardie plank and hardie shingle adds durability to the exterior.

The r 0 87 value for the first value in this air r value table subsection. James hardie recommends that you consult with your design professional if you have questions regarding exterior wall drainage on your single family project. Most siding in canada is installed with an air space between the siding and the wall itself. In order for both of these actions to take place when siding is installed correctly there needs to be a continuous space behind siding where water can drain and air can flow.

Common siding installation mistakes to avoid. Individual buildings all exterior cladding products including hard siding. Purlins at a 45 degree angle still provide sufficient support for installation of the metal roof panels. Synthetic stucco photograph 8.

Lightweight 50ft rolls of corrugated lath strip create a rainscreen air gap in both horizontal and vertical siding applications. Rising along the underside of the angled purlin until it reaches a gap then rising up to the next purlin and so on to exit at the ridge or gable. Rainscreen between flat to wall siding and the water resistive barrier as a best practice. With the air gap we get drainage and the control of hydrostatic pressure.

Does not consider internal convection effects does not consider presence absence of reflective barriers does not consider directions of heat flow up or down nor winter summer conditions. Mti s sure cavity and corrugated lath strip create a capillary break that prevents entrapped water and promotes airflow to dry out the siding and substrate. That air space is a key element of building what we call a rain screen wall. The air space between siding and sheathing should also allow humid air to escape.

Providing an air gap between the stucco cladding and the exterior face of the foam sheathing prevents the debacle we got with face sealed exterior insulated finish systems a k a. Back vent fiber cement siding to prevent swelling reduce maintenance and extend its life.