Security grilles for windows and openings answer a precise practical need — preventing unauthorised access — and that translates into technical requirements going well beyond the appearance of a steel grid.
Spacing between the bars
The distance between the vertical or horizontal bars is a technical parameter determining how effective the barrier is: too wide a gap defeats the purpose. That requirement, together with the thickness of the bars themselves, should always be agreed explicitly with the customer before calculating materials.
The fixings matter as much as the bars
A grille with sturdy bars but poorly anchored to the wall with inadequate fixings offers only the appearance of protection. The type of fixing needed depends on the wall material — solid masonry, hollow block, reinforced concrete — and should be assessed case by case, not standardised across every installation.
Resistance to levering and pulling
Beyond static strength, a security grille should resist attempts to force it with a lever or pull it away, a requirement that affects both material thickness and how the intersections are welded. Telling the customer clearly what level of protection a given configuration offers avoids expectations that do not match what is actually supplied.