H-5 Task 3

Question 1

what is total rise?

Answer 1

the starting point for all staircase calculations, measured from finished floor level at the bottom of the stair to the finished floor level at the top

Question 2

what is desired rise used for?

Answer 2

you use it for the next step in calculating stair dimensions, take your desired rise ( example. 180mm) and divide that by your total rise for number of risers

after desired rise, round up or down depending on decimal and stay within the min and max of building code

Question 3

how do you get rise per step?

Answer 3

after you have number of risers, divide number of risers by total rise for the rise per step

(2650mm/15=176.667mm) Rise per step= 177mm, round to the nearest millimetre

Question 4

what is a trapped run?

Answer 4

is a condition where the total run of the stair is fixed

Question 5

what is the allowance you add for finished opening?

Answer 5

75mm or 3”

Question 6

Staircase Rough Opening Formula?

Ratio proportion R.O. formula?

Answer 6

R.O.=
(UnitRun/UnitRise) x (headroom+floorthickness) + 75mm

FSO Unit Run
———————— = ————–
FT+Headroom Unit Rise

FSO=Finish stairwell opening
Ft= Floor thickness

Question 7

Unit of bridge formula?

Answer 7

Square root the √Rise^2+Run^2

√(177^2 + 273^2)