Abstract: Side pillar assemblies may include trim straps for structural rigidity during deployment of side airbag apparatuses. During deployment, the airbag can deploy from behind the roof head lining, above one or more pillar garnishes of the side pillar assembly and into the occupant compartment. A rib along the back surface of the pillar garnish may be placed in tension during a deployment event and inhibit fragmentation of the pillar garnish and limit movement of the pillar garnish into the occupant compartment. The rib may include one or more strap portions that may be placed in compression in the event of an impact on the interior facing portions of the pillar garnish. The strap portions may buckle under the compression force and provide a level of cushioning or energy dissipation due to the impact.