There are so many different types of ladders,

by:SanTong     2020-04-23
With so many different types of ladders the terminology can be confusing. Here are a few examples of transportable ladders to help you. Extension ladder - Constructed in several lengths, extension ladders can be extended, part by part to their full size. They sometimes have a rope and pulley system for easy extension with someone standing on the ground, locking securely in position. Step ladder - Invented in 1862 in the US, John Basely put a hinge in between two sides of a ladder for easy storage. Today, they remain at a locked angle using a mechanism. Multi purpose ladder - With one to three hinges multi purpose ladders can be folded into different shapes and configurations. They are ideal for uneven ground. Loft ladder - Used to gain entry into the loft or attic area, loft ladders are pulled downward from a ceiling and usually extendable or concertina design. Telescopic ladder - These ladders fit into themselves, much like telescopes. However, this does not necessarily detract from telescopic ladders strength or height and can be extended up to 380cm. They are ideal portable ladders. Hook ladder - These have hooks at the end to grip window sills and are usually used by firemen. Roof ladders - Specifically for climbing inclined roofs, roof ladders are lightweight, with a shaped hook and rolling wheels in order to attached it. Combination ladder - Combining the functions of extension ladders and large step ladders, combination ladders are regularly used in theatres to rig up lighting equipment. Fibreglass ladder - These are for safe working electricians to avoid conducting electricity. A brief summary of ladder development A ladder is such a common and ordinary object that not many people consider its origins. The word can be traced back to a similar Old English word meaning 'something that slopes' as well as being linked to the latin word 'clathri', referring to a set of bars. Its invention cannot be attributed to any one person since it can be traced back before recorded history. Ladders, as we know them, have been in use for over 10,000 years. Cave paintings in Spain were discovered depicting a long, rickety ladder, made from woven grass, against a tree housing a bees nest in order to collect honey. As tools progressed, wooden ladders emerged on the scene. They were used throughout the medieval era to invade castles so soldiers could scale walls to get inside to open the doors. At the same time, defenders would try and stop the army getting in using arrows and other projectiles. This meant the method was costly in terms of men. Modern ladders are much more versatile. Common materials include wood, aluminium or fibreglass and can be transportable or fixed.
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