STAIRS 3 rd YEAR TRADE Lesson Two M.S. MARTIN March 2005 Reviewed 2011 M.S. MARTIN March 2005 Reviewed 2011

Review Calculations Determine suitable rise & going of step to construct a closed riser timber staircase given the following. Rise of flight – 2.400m Going of flight – 3.900m Assume rise of – 170mm No. Risers = = say 14 Height of Riser = = say 171 No. of Goings = 13 (one less) Length of going = = 300 Check for easy going 2R + G = 550 to 700 (2 x 171) = 642 OK

Revise Definitions Handout Complete names on handout & review on completion

Types of Stairs Ref: Carp 18 Textbook – from P6

Straight Open Riser

Dogleg

Quarter Turn

Geometrical circular

Spiral or Helical

Types continued – from P5 - 9 Review text for type combination Brick Concrete Steel or Iron Other types Timber

BCA Your 2011 workbook on stairs (first section) Your text and other printed information, makes frequent reference to BCA requirements, review some of these in the handout

Timber Stairs Ref: Carp 18 textbook – P25 – 29

Open Riser Stair From P27 Also your first practical exercise Review these few pages in your textbook

Closed Riser Staircase Your 2011 workbook from P 36 Review Handout, this will be your second practical project

Rise of step Margin line Closed Riser Stair Set - out

Wedge Detail & Size Nosing line

Tread Detail of Housings

Closed Riser Staircase

Template you made in the workshop

Tenon Details Copy into your handout

Newel set - out

Newel set – out continued, also P23 carp 18

Stair calculations including length of string Example P31 – carp,18

Stair calculations Review example of calculations on P31 of your textbook

Complete exercises Workbook from P 17

“Extra” Calc’s exercise No. 1 Copy the following and complete Calculate the quantity of timber required for the open riser stair with following spec: –Rise of flight850mm –Going of flight1.100m –String material250mm x 38mm sawn H/W –Treads40mm thick sawn H/W –Width of stair1.200m –Assume rise160mm

Answer – note: this symbol √ below means square root No. of Risers = =5.312 say 5 risers Height of riser =.850= 170mm 5 No. of Goings = 4 Width of going = =275mm 2R + G =(2 x 170) OK Length of string √ (rise of flight)² + (going of flight + one going of step)² √.850² + ( )² √.850² ² √ √ = Order 1.8m lengths String 250 x 38 H/W 3.6 Treads 275 x 40 H/W 4.8 You don’t have to show all the working, but for this example it shows you the full answer

Calc’s Exercise No. 2 Copy the following & complete Calculate the timber order for a closed riser flight of stairs to suit the following spec: –Rise of flight2.450m –Going of flightunrestricted try 280mm –Rise of step approximately 160mm –Riser boards19mm thick maple, 20mm nosing –Treads40mm maple –Stringer350 x 40mm Maple –Width of stairs2.600m

Answer No. 2 No. of Risers = = say 15 risers Height of riser =2.450= 163mm 15 No. of Goings = 14 Width of going - unrestricted =280 =280mm 2R + G =(2 x 163) = 606 OK Length of string √ (rise of flight)² + (going of flight + one going of step)² √ 2.450² + ( )² √ 2.450² ² √ √ = Order 5.1m lengths String 350 x 40 Maple 5.1 Treads 300 x 40 Maple 5.4