The document provides information about setting out works for a building construction project. It discusses two common methods for setting out a building - using a circumscribing rectangle or the centerline method. The centerline method is commonly preferred. The procedure for the centerline method involves marking the centerlines of walls on the ground using pegs and string, then establishing the corner points by setting perpendiculars at intersections using techniques like the 3:4:5 method. An example problem demonstrates marking the positions of pegs on a plan to set out a rectangular building with dimensions and foundation details provided.

1. Royal University of Bhutan
Jigme Namgyel Engineering College
Department of Civil Engineering & Surveying
Tutor : Phurba Tamang
Designation: Associate lecturer
Department of Civil Engineering and Surveying
SETTING OUT WORKS
MODULE: SURVEYING
Spring Semester 2020

2. MID-TERM REVIEW, 2017
Setting Out Works
Introduction
Setting out is a survey undertaken in order to transfer onto the site, the plans prepared as a result
of some previous survey. Here, instead of using data from the site to prepare plans, the plans and
designs prepared by the designer are transferred accurately onto the actual site. It may be
described as the fixing of well defined points in the filed showing the horizontal and vertical
positions required by the plans.
To build according to the plan, a contractor must have reference lines and points established in
the field. This involves placing of pegs or marks to define the lines and levels of work where after,
the construction proceeds according to these marks. Some factors to be considered during setting
out works are:
1. The reference lines and points should be well defined, not easily perishable, close to the work
yet out of way or actual construction operations.
2. A very high degree of accuracy should be maintained and only extremely low tolerances
should be allowed. In order to achieve this, frequent and independent checking should be
done.
3. The instrument used should be checked frequently and discrepancies if any should be
removed.

3. MID-TERM REVIEW, 2017
Setting Out of Buildings
Setting out of a building involves the transfer of the architect’s plan form paper onto the actual
site. The objective of setting out a building is to provide the builder with clearly defined outlines for
excavation. Two methods are generally used for setting out a building.
A. By Using a Circumscribing Rectangle

4. MID-TERM REVIEW, 2017
Setting Out of Buildings
A. By Using a Circumscribing Rectangle
Since stakes cannot be set at the exact corner points of a building ( if set so, these will be lost
during excavation , these are fixed at the corner of a bigger rectangle circumscribing the actual
building. Any suitable distance of the outer rectangle from the building can be chosen, but a
distance of usually 2 to 4 m is considered to be ideal. The actual procedure consist of the following
steps.
a. Preparation of the foundation trench plan showing the width of the foundation for various
walls.
b. Temporary pegs are driven at the actual corner points of the buildings.
c. Then using these pegs as reference a parallel line say AB of required length is set out at an
arbitrarily selected distance ( say 2 m ) from the actual center line.
d. A chord is stretched between the pegs A and B. At A, a line is set out perpendicular to AB
( with a tape using 3, 4. 5 method ). On this line, the position D is marked by setting a peg.
e. Set (d) is repeated at point B so as to obtain point C.
f. Having now set out the reference rectangle ABCD, the actual corners can be marked using the
sides of the reference rectangle ABCD.
g. Once all the points are staked, a chord is passed around the periphery of the rectangle and the
actual excavation lines are marked using lime.

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Setting Out of Buildings
B. By Centerline Method

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Setting Out of Buildings
B. By Centerline Method ( Commonly Preferred )
Procedure
a. From the plan, the centre lines of the walls are calculated. Then the centre lines of the rooms
are set out by setting perpendiculars in the ratio 3:4:5. Suppose the corner points are A, B, C,
D, E, F and G which are marked by pegs with nails on top.
b. The setting of the corner points is checked according to diagonals AC, BD, CF and EG.
c. During excavation, the centre points A, B, C,…. may be removed. Therefore, the centre lines are
extended and the centre points marked about 2 m away from the outer edge of excavation.
Thus, the points A1, A2, B1, B2 . . . . . are marked outside the trench. The centre lines are shown
clearly by stretching thread or rope.
d. From the plan, the width of excavation is found out and set out around the centre. The
excavation width is also marked by thread with pegs at appropriate positions.
e. The excavation width is then marked by lime or by making a furrow with a spade.
f. If the plan is much too complicated and follows a zig zag pattern, the centre pegs are kept at
suitable positions according to site conditions.

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G
List of Equipment for Staking Out
• Ranging Rods
• Wooden Pegs with Nails on top
• Measuring Tape
• Thread or Rope
Ranging Rods
Wooden Pegs
Measuring Tape
Thread or Rope

8. MID-TERM REVIEW, 2017
G
3-4-5 Method
Note: Any Multiple of 3, 4, 5 can be used. Example: 6, 8, 10 or 12, 16, 20, etc.

9. MID-TERM REVIEW, 2017
G
3-4-5 Method
Source: http://auromafrenchvillaments.blogspot.com/2014/02/marking-of-excavation-pits.html

10. MID-TERM REVIEW, 2017
Setting Out of Buildings
Example:
Describe the procedure of setting out of a two storeyed building with 200 m thick load bearing
outer walls all around. The foundation width is 750 mm. The building is absolutely rectangular and
outside dimensions above plinth level are 12000 mm x 18000 mm. Draw the foundation plan of the
outer walls showing all the dimensions ( not to scale ). In the above plan show the positions of
different pegs required for setting out of the above building.
Solution:
The Outside Dimensions are 12000 mm x 18000 mm
Thickness of the wall: 200 mm
Center line dimensions are ( 12000 – 200 ) = 11800 mm and ( 18000 – 200 ) = 17800 mm
= 11800 mm x 17800 mm
With foundation width 750 mm, the outside dimensions of foundation wall are 12550 x 18550
Inside Dimensions are 11050 x 17050.
Here the OFFSET PEGS are used.

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Setting Out of Buildings
Wall thickness 200 mm

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Setting Out of Buildings
Reference line connected by Thread or Rope
Maintained at 2 m from the outer wall

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Setting Out of Buildings

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Setting Out of Buildings

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Setting Out of Buildings
Steps:
• Mark the centerline of the longest wall on the ground by stretching a string between offset
pegs 1 – 1.
• Similarly stake strings along 2 – 2, 3 -3 and 4 – 4.
• Pegs marked as red dots in the figure are the reference pegs for all the other pegs.
• These pegs are marked at 2 m offset from all sides of the building plan. The pegs should project
25 to 50 mm above the ground level.
• The intersections are maintained at right angle using the 3:4:5 method or tri-square.
• Referring to the reference pegs ( marked red ) other temporary pegs are established ( marked
purple ).
• Once all the pegs are fixed, the lines are marked with lime.
• Once the lines are marked with the lime, the pegs are removed except for the reference pegs.