The task of framing a building has been estimated to take an average of 25 days with a standard deviation of four days. What duration should be used if there is to be a 90% confidence that the duration will not be exceeded? What is the proba- bility that the duration will actually exceed 23 days?

Q: What are master specifications?

A: Master specifications are a compilation of standardized, guide specifications or pre-written…

Q: What materials are included in Division 9 of the MasterFormat?

A: Some divisions of the Master Format are : Division 6 - Wood and plastics Division 7 - Thermal and…

Q: Write a few lines on RFI?

A: Request for information is a process of business in which the main motto is  to collect the…

Q: What is UBC Standards?

A: - Uniform Building Code (UBC) is building construction code guidelines book used in United states of…

Stair construction and layout

Stair is a type of vertical transportation in a building which consist of a series of steps in a flight of stairs that enable the vertical movement of people and materials from one floor to another. A staircase consists of steps that comprises of riser & tread, handrail, baluster, stair stringers, newel post and waist slab. The construction of staircase with all the components is termed as stair construction. A staircase is an enclosure that contains the entire stairway. The materials used for the construction of stairs are bricks, reinforced cement concrete, stone, lumber, steel and a combination of these materials.