How to install bitumen shingles on concrete roof decks – introducing Armourbase Thermo AD

A stable and smooth roof deck is crucial for obtaining a solid roof. The most popular material used on the European market for roof structures is wood. A full deck for shingles is often built from OSB, plywood or wooden planks, followed by an underlayment and bitumen roof shingles that are nailed with roofing nails into that deck.

But in some other parts of the world, such as Southern Europe, Africa, Middle East or Southeast Asia, the roof structures and decks are made from solid concrete (as lumber is not always available) People in these areas built solid houses and roofs to protect themselves against bad weather, strong winds and heat. Using concrete provides them certainty in these circumstances.

IKO Shingles on concrete sloped roofs

As from spring 2021, IKO will offer 2 solutions on how to apply asphalt shingles on concrete roof decks. Fixing the shingles with special concrete nails is a first solution for slopes > 15°. For slopes > 4° -15°, shingles cannot be fixed mechanically. IKO Shingles can be flamed on Armourbase Thermo AD, a new underlayment in the IKO product portfolio providing a waterproofing layer and a perfect upper face to stick/flame shingles upon.

Nailing method

The structure must meet the local national material standard and all applicable code requirements for local construction. The roof must be sufficiently supported to accommodate all anticipated roof loads during the installation of the tiles and the subsequent roof load. The concrete roof must be covered with a smooth layer of mortar with a thickness of 25 to 30 mm.

The mortar should be made on a ratio basis, with one part cement and 3 parts sand. The mortar must be covered with a layer of waterproof asphalt primer (Primer AD), which must be allowed to dry completely before installing shingles.

The roof details

On the hip and ridges, the underlayment is already covered with shingles. Therefore hips and ridges are installed with gluing the parts. On a concrete deck, a piece of 30cm is trimmed from Armourbase Thermo AD and torched on the top part of the roof over the last rows of shingles.  Then the capping can be torched over this membrane.


IKO has two quick solutions for the installation of shingles on a concrete deck. With durable concrete nails the application is very fast but it very much depends from the quality of mortar layer. An advantage here is that shingles can also be installed on slopes higher than 45°.

The torch-on application with Armourbase Thermo AD is a  progressive method which is capable of solving specific application (concrete roof decks, low slope roofs) and functional requirements. The method presents numerous and important advantages, such as an easy application with consequential savings on time but has limits on steep slopes (max. 45°).


NOTE: With this new method you can also install all types of IKO shingles on very low slope OSB decks. The deck should be made out of OSB with a tooth and groove locking system. This is to ensure that there are no gaps between the boards. The shingles then can be applied by the flaming of Armourbase Thermo AD without the use of roofing nails. Application slope for OSB decks with this method is from 4°- 15°.