I have gained a lot on most of write up on measurement, pls I want u to write on staircase measurement. Thank you.
Staircases are series of steps with their framework that leads human and materials to higher floor of a building. That is the building with stairs that links to the next floor from whatever floor you are in a storey building.
There are different building components that can take you from one floor of a storey building to the other like elevator/lift,escalator etc but we are concerned on staircases for this article.
There are different types of staircases by materials and designs.
(i)By materials-Staircases can be steel / iron,wood,concrete etc these are the three major ones but you can also design with other materials even bamboo and special glasses.
(ii)By design-This is about the style of your staircase which could be determined based on the purpose you want to use it for, we have L shaped,U shaped or doglegged,straight flight,spiral, elliptical etc
For the simple concrete type of straight flight which we are discussing all we need is to first establish the height of the room that is the length from the lower floor to the base of the upper floor, this will help to determine the type of staircase that can also be suitable.
The major components of staircases are risers,thread,stringer,landing,handrails,nosing etc
Risers are the vertical parts of the stairs that takes you up as you are climbing, this is usually in the range of 120mm-175mm, however 150mm is taken as the ideal height for each riser which must be equal allround to avoid accident or tripping when climbing by the users.
Thread is the horizontal member of the stair, this is usually between 250mm to 300mm, is the short platform you step on as you climb the stairs hence the reason for 300mm or 1 foot length to be able to accommodate substantial part of your foot (leg).
Stringer which may not be applicable in some staircases is the side support that the thread and riser are hinged or connected to which clip the staircase together from the ground to the upper floor.
Landing is a bigger portion of the staircase which you can rest for a while after climbing some numbers of stairs , usually they are in between U and L shaped staircases.
Nosing is that extra tip of thread that shoots out beyond each riser, though this is no longer common because of tripping/accident.
Handrails are used as support to help protect you from falling off the staircase, this also can be any material from wood,steel/iron,concrete etc
To determine the thread and riser of a simple staircase such as showed in image above, first consider the height from the ground,choose the thread width to know if the space available can take the staircase, if need be consider a landing too of a minimum width of 900mm especially for a U or L shaped staircase.
Remember the riser is between 120mm to 175mm but we can use 150mm which is most commonly used.
Also note that staircases that are steep can cause accident and not acceptable. But working within the acceptable dimensions for risers and threads will help to achieve a good slope.
For a floor of headroom height of 3m or 10ft,divide by 150mm, it gives 20 risers from the present floor to the base of the upper floor, now consider the thread which is one less to total numbers of risers to be 250mm, multiply 250mm by 20 risers, and you’ll have a length of 5meters as the space required for the staircase to run. For space constraints and design when you want to do your calculation you may opt for U or L shaped staircase. Remember additional minimum of 0.9m or 900mm for landing width.
To do the construction proper for concrete staircase of straight flight as shown above ,Lay a straight board consisting of planks nailed together and extend from the base of starting of staircase to the base of the upper floor where staircase will land. Using builder’s square and pencil, mark out the threads and risers on stringers or on supporting walls as the case may be then begin to place the planks cut to riser heights to each riser markings on the wall until you get to the top, though this is done when the iron rods that will support the concrete has been placed on top off the bed of plank.
After this you can do the concrete casting, allow to cure for 21 days just as it is with concrete decking before you remove the supporting board underneath which are also supported by bamboo sticks or 2 by 4 timber which serves as props.