DRAWING PRACTICE

LESSON OBJECTIVES

Explain the concept of drawing to scale

Use a scale rule to find a variety of measurements

State the commonly used scales for Block and Site plans

Explain the use of hatchings in drawings

THE CONCEPT OF DRAWING TO SCALE Buildings and parts of them are invariably drawn to a reduced scale. For instance, a wall 1 m (1000 mm) high may be represented on a drawing by a line 100 mm long which is a tenth of 1000 mm. The ratio of 100 mm to 1000 mm is more conveniently expressed as 1 to 10, and is normally written as 1:10 and called "the scale".

Using scale rules Scale rules are usually marked with eight different scales, two on each of four edges using both sides of the rule.

 Hatching is a term given to the markings on a cross sectional drawing used to indicate the material that it is constructed of.They are official British Standards and can be found in BS: 1192 which controls drawing practice across all sections of the Construction Industry 

Working DrawingsA working drawing and written specification should contain the total information required for a building team to convert the architects proposed building into a completed structure. To enable this to happen the following information should be found in the following locations.

ELEVATIONS: 1. External finish to walls and roof  2. Position of window and door openings Scale used 1:200, 1:100, 1:50

PLANS: 1. Overall dimensions of the building 2. Position of internal walls, room sizes door and window openings 3. Position of fitments, baths, sinks toilets, stairs etc

Scale used 1:200, 1:100, 1:50

Working Drawings

SECTIONS:  1. Provide vertical dimensions 2. Provide constructional details of foundations, floors, walls, roof, damp proof membranes and ground

levels

Working Drawings

SITE PLAN: 

Position of the building in relation to the site surroundings i.e. adjoining buildings, roads, boundaries, etc.Provision of access, Drains and main sewer. Shows North point

Working Drawings

The drainage layout should be used in conjunction with the drainage schedule, which will give details of manhole construction, cover and invert levels, and other relevant information.

BLOCK PLAN: 1. Location of site in relation to surrounding district. This is taken from local authority’s ordnance survey map

Working Drawings

The scale is usually 1:2500, 1:1250 and is too small to allow much more than an outline of the site and boundaries, road layouts and the other buildings in the near vicinity.

COMPONENT DRAWINGS: These show the basic sizes of standard components such as doors, windows and kitchen fitments. scales most commonly used are 1:100, 1: 50, 1: 20

Working Drawings

LEGAL or TITLE PANEL: 1. Site Address 2. Scales used on drawing 3. Drawing Number 4. Client 5. Date of drawing 

J & M BuildersDrawing No 235 W R Smith10 GreenwaysGreenhamScale 1:100 March 2003Drawn CPR

J & M BuildersDrawing No 235 W R Smith10 GreenwaysGreenhamScale 1:100 March 2003Drawn CPR

Working Drawings

DETAIL DRAWING: These drawings will include every detail required to make the product. The information from these details is used to manufacture various components .These drawings are usually produced by the architect and are produced in scales ranging from 1:1, 1;5, or 1:10.

Working Drawings

ASSEMBLY DRAWING: These drawings are very important to the builder. They show in detail how the architect requires the construction to be constructed and what materials should be used .The scales usually used for these drawings are 1:20, 1:10, 1:5 and should be fully dimensioned and annotated.

Working Drawings

Key Points• Select drawing required consulting Index if available

• Ensure it is the latest amended version

• First, get an overall picture before looking at details.

• Check the sum of intermediate dimensions equals the overall dimension

• Do not scale from drawings

• Take every opportunity to compare drawings with the current construction