In case of ceiling’s thickness above standard 28cm the ladder features a metal grid equal to the space between floors.
Installation will be same as standard ladders, pulling up into the opening. 

The presence of a slab greater than 28cm (both fully load-bearing and composed of plasterboard) implies the need to overcome a significant difference in height. 

The difference in height is formed every time because the ladder is always hooked to the hinges of the panel and therefore cannot be hooked higher: it would be impossible to open and rotate the ladder correctly. 

It follows that the void cannot be overcome except with the aid of intermediate welded steps, which facilitate the ascent and descent in complete safety. Inside the superstructure, a number of steps equal to the risers present are welded, 30cm by law (e.g. slab thickness 90cm = 3 risers = 2 steps) 

For safety reasons the steps are welded to two diagonal bars, as you can see in the images and in the video. The bars with the welded steps will occupy a diagonal space along the length of the hole of approximately 10 cm for each intermediate step added. 

This method leaves a littler hole available for ascent and descent, since each intermediate step added in the superstructure needs approximately 10 cm to be welded diagonally. The usable hole will be inferior  (considering the original length).

Let's take a very common practical example: 

Total thickness of the supporting slab: 90cm 

Existing hole available: 100 × 70 

Rises required inside the hole: 3 

Intermediate steps: 2 (20cm of welded fixed part used to allow the diagonal installation of the 2 steps) 

Final usable hole: 80 × 70 

 In the estimate phase, the ideal  model for the new available length will be calculated. In addition, it is possible to estimate a drop-ceiling ladder for the "external roof access" model.

ATTENTION:  All technical assessments are carried out in the design phase of the final quotation.