All the information and instructions you need for a construction task can be found in the plans and specifications for the project. In this chapter we will talk about:
Australian standard AS1100.301 for Technical and Architectural Drawing outlines the types of drawings that are commonly used in the building industry. You can refer to clauses 1.5.2.2 and 1.5.2.3 of the standard if you want to know more.
Drawings are described under two main headings:
Drawings at the design stage of a building project are generally pictorial views which present the designer’s ideas in what is sometimes called an artist’s impression.
These views can be either hand drawn or computer generated using drawing techniques such as perspective and isometric projection. The illustration above shows a hand drawn perspective sketch of a house. 145 Hand drawn pen and ink perspective sketch.
The illustration below is a typical computer generated image produced at the design stage of a project. AS1100.301 describes these types of design sketches as schematic drawings.
Other types of design drawings could look like aerial views of the project. These drawings are usually rendered views of the buildings and their surrounds which present the designer’s ideas for the layout of the whole project. Often called project or development drawings, they are used as a basis from which accurate working drawings can be made.
The illustration above shows a rendered development drawing used in the design stage of a retirement village project.
Production or construction drawings are accurate scale drawings. Together with the specification, they contain all the information that is required to complete the building project.
AS1100.301 describes drawings for the production stage of a project as follows:
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ tr /f ][ What is the australian standard that refers to drawings used in the building industry? (type it carefully) ][ AS1100.301 ][ AS1100.301 is the specific standard. ]]
[[ mr /r /f ][ Which clauses will give you more information? ][ * 1.5.2.1 ][ 1.5.2.2 ][ 1.5.2.3 ][ * 1.5.2.4 ][ Clauses 1.5.2.2 and 1.5.2.3 contain more information. ]]
[[ mr /f ][ Which of the following fall under the general classification of Location Drawings? ][ Floor plans. ][ Drainage plans. ][ * Fine construction detail. ][ * Special fittings. ][ Elevations. ][ Special fittings and fine construction detail would be classed as component rather than location drawings. ]]
The drawing below is a simple site plan for a pole house. Site plans show boundary dimensions of the block and the position of the building. Other information such as the direction of north, driveways, levels and scale will be required on site plans as well. A more detailed site plan for a construction project will be discussed later in this chapter.
A floor plan is the horizontal section of a building which is viewed from above. A floor plan of the pole house is shown below.
A fully dimensioned floor plan should show overall sizes, room function and sizes, window sizes and positions, door sizes, wall thickness, cupboards, appliances and fittings. Only overall dimensions have been included in the example on the previous page. We’ll look at a complete floor plan later.
Elevations are views seen from the front, back or sides of the building which show vertical dimensions such as the height from floor to ceiling, shape of the building and its features, windows and finish to external walls.
Dimensions and other information have been left out the following elevations at this stage so you can get a better idea of the shape and features of the building. We will look at more detailed examples of elevations later in this chapter.
Elevations are sometimes named according to the direction they face. The North Elevation would be the aspect of the building facing north (shown on the site plan). Elevations are also named Elevation A, Elevation B and so on.
The East Elevation of the house is shown above. The Site Plan shows the direction of north. To determine which direction is east, face north and east is on your right.
A section is an elevation cut through the building at a position shown in the floor plan. Have a look at the Floor Plan on page 147 for the position of Section A-A is shown below. These drawings give a cross section of the building through the footings, floor, walls, ceiling and roof structure.
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ mm /f ][ Match the construction drawing with the appropriate description: ][ Site Plan ~ Shows boundary position and building position. ][ Floor Plan ~ Horizontal section of the building from above. ][ Elevation ~ Front, back or side view of the building. ][ Section ~ A view cut through the building. ][ Site Plan => shows boundary / building position; Floor Plan => building seen from above; Elevation => Front, back or side view; Section => a cut through the building. ]]
The title panel or title block on a construction drawing generally contains the following information:
The layout of title blocks can vary quite a lot but all should include any amendments or revisions that may have been made to the drawing. A typical example of a title block is shown below.
Information about revisions or amendments may vary in the way it is shown in a title panel. It may be as simple as including the revision date or more information could be provided as in the example above.
Before you take any information from plans you should check to see that they are current. This means they should be the latest revisions that have been given final approval for construction. Look at the Revisions section in the example above.
Also have another look at the chapter on Planning Your Work to remind you that it is very important to check all task requirements.
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ mc /f ][ Which of the following is not likely to be included in a drawing's Title Panel? ][ The cost of the works. ][ * The client's name. ][ * The project name. ][ * The revision information. ][ * Initials of the draftsperson. ][ It is unlikely that the cost of the works would be included. ]]
[[ mc /f ][ How will you know that the plans that you have are the correct ones to use? ][ An "approved for construction" date is present. ][ * The correct initials are present. ][ * The drawing number is correct. ][ * The issue date is correct. ][ * The issue number is correct. ][ Plans must be approved for construction before they can be used. ]]
Australian standard AS1100.301 for Technical & Architectural Drawing recommends symbols for a number of items that are generally shown in the plans for a construction project.
Examples of some of these items and their standard symbols are shown in the table below.
Architects and engineers often use variations of these standard symbols.
Computer programs that are used to produce construction drawings generally have a range of symbols built into the program.
These symbols are usually more detailed than the basic standard symbols shown in the table above.
The drawing below shows part of a floor plan for a toilet facility.
You will notice that the symbols used for the basin and water closet (toilet) are not the same as the basic standard symbols in the table.
Some designers also create their own symbols for these items and other common drawing components using a CAD program which allows the operator to import the symbols into their drawings.
The table below shows standard symbols used for hatching and presentation of some common materials used in the General Construction industry.
These and other symbols were devised as part of an Australian Standard to make sure construction drawings are presented in a uniform manner.
Abbreviations are used in plans to convey information with the least amount of clutter. Cluttered drawings can be difficult to read.
The table on the following page lists some of the abbreviations that are used in construction drawings.
For example, a floor plan for a kitchen might include an oven, a refrigerator and a dishwasher.
Abbreviations for these items would be used on the plan if necessary, in preference to the full names which would tend to clutter the drawing in the limited space of the kitchen layout.
These items would usually be shown on the drawing as a rectangle or square with one or two diagonals drawn in if space permits.
A legend is a list of items in a construction drawing. When symbols and abbreviations are used in a drawing it is common practice to show a list or legend of these items. This is helpful where non-standard symbols and abbreviations have been used in a construction drawing.
The example above is a typical legend included in the floor plan of a house.
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ mm /5 /f ][ Can you match these abbreviations with their respective meanings: ][ WR ~ Wardrobe ][ WO ~ Wall Oven ][ WM ~ Washing Machine ][ WC ~ Water Closet ][ WMR ~ Water Meter ][ WP ~ Waste Pipe ][ WPM ~ Waterproof Membrane ][ WH ~ Window Head ][ WR = Wardrobe; WO = Wall Oven; WM = Washing Machine; WC = Water Closet; WMR = Water Meter; WP = Waste Pipe; WPM = Waterproof Membrane; WH = Window Head ]]
You will need to be able to read important information from scaled construction drawings when you undertake a construction task.
Plans are drawn smaller than full size so they will fit on standard size drawing sheets. If a building is drawn to a scale of 1:100 every detail on that drawing is reduced to one hundred times smaller than its full size. For example, a full size measurement of 3600 would actually measure 36 on the drawing but would be dimensioned as 3600.
The photograph below shows a cottage which has been constructed in a village development. To help you understand the importance of plan reading we will follow construction of the cottage starting at the site.
The site plan (scaled at 1:125 to fit the page) is shown below. This plan shows the boundary dimensions of the block, distance from boundaries to the building, direction of north, position of the driveway, lot number, water main, sewer main, contour lines and heights. Note also the datum points from which measurements can be taken to locate or check positions and levels on site.
Working from the site plan, construction workers locate the exact position of the cottage on the site so they can set out its shape in preparation for constructing the footings.
Other plans will be used to get information for the next stage of construction.
Foundation plans are prepared by civil engineers to council requirements. Soil tests are carried out first so the engineer can work out how strong the footings need to be to properly support the building on that site. The size, amount and design of reinforcing used will depend on the result of the soil test.
The plan for the footing layout (Dwg. No. 02) is shown on the below. The dotted lines on the plan give the positions of the reinforced concrete footings.
The footings will be constructed in trenches that are excavated to the depth shown in the plans.
The photograph above shows workers setting out the shape of the cottage and its footings from the construction drawings.
The footing layout (Dwg. No. 02) has a legend which contains coded information about footing types and reinforcing steel. You will need to understand these codes so you can read the drawings.
Explanation: The item P1 in the legend refers to ‘1-N12’. This is a method for showing number, type and size of reinforcing bars to be used.
1-N12 means ‘one piece of hot rolled deform bar twelve millimetres in diameter’. 2-R10 means ‘two pieces of structural grade plain round bar ten millimetres in diameter’.
The symbol above is from the top left corner of Drawing No. 02. It is a typical method of cross referencing information in a set of plans. The letters C-C stand for Section C-C and 03 means that Section C-C can be found in Drawing No. 03.
The engineer’s foundation plans contain all the graphic detail and other information required by the steel fixers who assemble and place the reinforcing steel before concrete can be poured.
Drawing Number 03 below shows just a few of the detail drawings that would be necessary to complete this task.
Study the footing details on Dwg. No. 03 then have another look at the footing layout on Drawing Number 02. Note the differences between the details for B1 and B2 and Section C-C.
Engineers generally refer to individual footings as beams, hence the abbreviations B1 and B2. One difference is that type B1 beams around the perimeter of the building are deeper than the internal type B2 beams.
Can you think of a reason why the R10 hoops aren’t as close together in the B1 beams as they are in B2 beams?
Section C-C shows that the B1 beam next to the carport is 400 wide. Can you see a reason for the extra width?
Before the slab can be poured all underground work such as waste pipes must be installed. Their exact locations are read from the plans. The kitchen and bathroom waste pipe locations can be seen in the photograph above.
The floor plan for the cottage (Drawing No. 04) is shown below, drawn to a scale of 1:100. Because of limited space, dimensions have been shown on a separate dimension plan (Drawing No. 05) on page 162. The dimension plan has been drawn to a non-standard scale of 1:140 so it will fit on the page.
The photograph below shows a concreter removing the formwork and putting the finishing touches to the edges of the slab.
Formwork must be set up accurately so the slab is the right size and shape, in the correct position on the site and at the correct level.
These are important measurements which must be carefully checked from the plans before concrete can be poured for the slab. You must always remember that the work of others will depend on the accuracy of the work that you do. A mistake made because a drawing was not read correctly could cause very serious problems as construction progresses.
In the next stage of construction, the wall frames of the cottage will be erected on the concrete slab.
The photograph above shows carpenters using a chalk line to set out the position of the wall frames by working from the floor plan.
The floor plan shows horizontal length and width measurements. You can find height measurements in the elevations.
The photograph above shows wall frames standing on the floor slab. Height from the floor to the ceiling and the height of the window heads have been taken from the elevations below.
Elevation A below is a two dimensional view of the front of the cottage. Compare the features of the cottage in Elevation A with the photo on the left. For example, look at the carport in the photograph then see how it is shown in Elevation A.
Elevation B below is a view of the back of the cottage. Compare this view with Elevation A on the previous page. You will notice that the carport is on the right and the pergola is on the left in Elevation B. In Elevation A the carport is on the left and the pergola is on the right. Why do you think this is so?
Elevation C on the page opposite is the view of the side of the cottage where the carport is to be constructed.
The photograph below shows some of the detail on this side of the cottage.
Elevation D on the page opposite is the view of the side of the cottage where the pergola is to be constructed.
The photograph above shows detail of this wall of the cottage and the pergola. Note also the sliding glass door that provides access to this outdoor area.
Section A-A on the opposite page is like an elevation but appears as if part of the building is cut away and you are looking at the part that is left. The position of this section is shown in the floor plan by the symbol on the right. The symbol tells us that the drawing of Section A-A is in construction Drawing No. 09.
The symbol below is used to subtitle the drawing of the section. This symbol tells us the position of Section A-A can be found in Drawing No. 04 (the floor plan).
Section A-A gives a cross section of the cottage through the footings, floor, walls, ceiling and roof structure. Much of the information in this drawing can also be found in other drawings or specifications. However, some information may only be shown clearly in a section.
Examples in this case are the insulation in the ceiling, the foil sisilation under the roof sheeting and the structure of the roof.
The photograph below shows the roof trusses and other framing members that are shown in the sectional view A-A.
Section A-A contains quite a few notes which provide important construction information. These notes are part of the overall specification for the project so you must read them carefully and follow them as the job progresses.
The drawings included in this text are not a complete set of plans for the project. Construction details for bracing of the framework, drainage and electrical layout are examples of other drawings that are generally required.
Minor details that are standard construction procedure are usually left out of the plans. Unnecessary details tend to clutter a drawing and make it more difficult to read. For example, wall and ceiling linings, cornices, skirtings and architraves have not been shown in Section A-A.
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ mc /r /f ][ The datum points on the site plan are clearly indicated by the letters "dp" on the corners of the building - true or false? ][ * True ][ False ][ The datum points are at the corners of the site; "dp" indicates the location of a downpipe. ]]
[[ mc /f ][ The footing layout has no dimensions on it. How do the concretors know / find the dimensions of the slab? ][ * They use the scale and measure the plan. ][ * They ask the building supervisor. ][ They refer to the site plan. ][ * They use their prior knowledge. ][ The site plan is the point of reference. ]]
[[ mc /f ][ The footing detail drawing has no units on the dimensions. How do you know / find out what the units are? ][ The units are understood to be mm. ][ * Use the scale to work it out. ][ * Ask your supervisor. ][ * Concretors have their own units. ][ Construction dimensions are understood to be mm if none are included. ]]
[[ mc /f ][ On the floor plan, where is the electrical meter box located? ][ Under the pergola. ][ * Next to the front door. ][ * Outside the bathroom. ][ * In the carport. ][ * Outside the storeroom. ][ The electrical meter box is just outside the kitchen, under the pergola. ]]
[[ mr /f ][ Looking at Dwg. No. 09 (the section drawing), what thermal insulation is included in the building? ][ Sisalation under the roof sheeting. ][ Bulk insulation above the ceiling. ][ * Wall insulation. ][ * Underfloor insulation. ][ The only insulation mentioned is under the roof and above the ceiling. ]]
Specifications are the written instructions which you must read in conjunction with construction drawings. Specification documents detail the work for each trade involved in the construction project as well as giving other general information.
The setout of specifications may vary to some extent but a standard specification will generally include instructions for the following trade areas:
Specifications for a project can range from a few pages of notes to a large document of one hundred pages or more depending on the project. To give you an idea of the kind of information and instructions that can be included in specifications, the following extracts have been taken from several different specification documents. Always check that a specification is the current revision before you use it.
This example of siteworks instructions is an extract from a brief specification document for a small residential building project.
All topsoil containing vegetation and organic material is to be stripped from the confines of the construction site. The fill material and the top 150mm of natural material in any cut section are to be compacted (in layers for fill material) to attain a uniform field density of 95% standard compaction.
The degree of compaction is to be verified using a compaction test. Compaction testing to be carried out to AS1289 ‘5 Series’ to achieve 95% standard compaction. All works to comply with AS3798 ‘Guidelines For Earthworks For Commercial And Residential Developments’.
If ground water is encountered or the site is known to have a history of ground water problems, a sub-surface rubble drain with slotted agricultural pipe will be required. The drain to have a minimum depth of 1200mm or to the maximum depth of fill.
The building platform is to fall away from the house at 1 in 20 minimum. If fall is to be achieved by placing topsoil after footings are constructed, over excavate these areas as required to comply with local authority requirements regarding difference between slab height and finished ground level. (Generally 250mm minimum). Drainage on flat sites is to be achieved by increasing slab lift by using imported fill platforms.
Discharge downpipes as per hydraulics drawings.
Refer to CSIRO Information Brochure 10-91 for site foundation maintenance.
The following is an extract from a detailed specification document for a large commercial building project. This section covers painting and clear finishing of surfaces.
5.04 Painting And Finishing
(a) Standard
To AS 2311 Sections 3, 6 and 7, or to AS 2312 Sections 5, 8 and 10, as applicable.
(b) Order of work
Complete clear timber finishes before commencing opaque paint finishes in the same area.
(c) Protection
Remove door furniture, switch plates, light fittings and other fixtures before starting to paint and refix in position undamaged on completion.
(d) Restoration
Clean off marks, paint spots and stains progressively and restore damaged surfaces to their original condition. Touch up damaged decorative paintwork or misses only with the paint batch used in the original application.
(e) Substrate preparation
Use filler tinted to match the substrate if the finish is transparent.
Previously painted surfaces:
(f) Paint application
Apply the first coat immediately after substrate preparation and before contamination of the substrate can occur. Ensure each coat of paint or clear finish is uniform in colour, gloss, thickness and texture, and free of runs, sags, blisters, or other discontinuities.
(g) Spraying
Clear finishes: Do not use airless spray for clear finishes.
Do not spray touch up paint to Colorbond finishes. Use a soft brush for application only if directed by the Architect.
(h) Repair of galvanising
Where galvanised surfaces have been subsequently welded, prime the affected area with two coats zinc rich organic binder and a finish coat to match galvanising.
(i) Paint system description
If a paint or clear finish system is referred to only by its final coat (for example by the manufacturer’s brand name, or the generic name) use in addition to the final coat, the appropriate stains, primers, sealers and undercoats, suitable for the substrate and compatible with the finish coat and each other.
(j) Number of coats
Unless specified as one coat or two coat systems, each paint system consists of not less than three coats. Provide additional coats if necessary:
(k) Tinting
Tint each coat of an opaque coating system so that each has a noticeably different tint from the preceding coat, except for top coats in systems with more than one top coat.
(l) Colour scheme
All painting work shall be carried out in accordance with a future Colour Scheme which will be issued by the Architect.
This example is typical of a simple concrete specification for a small residential construction project.
All work and materials shall be in accordance with the current edition of AS3600.
Minimum cover of reinforcing steel to be as follows: Footings 50mm top and bottom, sides 75mm; Internal Slab 20mm; External Slab 30mm.
Lapping and tying of mesh is to be in accordance with the current edition of AS3600.
Lap all reinforcement bars as follows: N12 600mm, N16 700mm, N20 900mm.
All reinforcement is to be supported in its correct position so that it cannot be displaced during the concrete pour. Bar chairs supporting reinforcement shall be no less than 600mm apart and 400mm at laps.
All concrete to be N20 grade minimum.
All concrete is to be vibrated.
Concrete faces are to be scabbled at construction joints before placement of adjoining concrete.
For finishing slabs poured in rapid drying conditions such as high temperatures or high winds, use Confilm Evaporative Retardant and finish in accordance with the manufacturer’s specifications.
This example is typical of a carpentry specification for a small timber framed residential construction project. Because standard specifications are listed in detail in the industry references, very few additional requirements need to be included in a basic specification document.
Notes on the construction drawings will generally contain most of the additional information the carpenter requires.
All work and materials shall be in accordance with the latest editions of the following industry standards and references:
AS1684.2-1999 Residential Timber Framed Construction (non-cyclonic areas)
AS1686.3-1999 Residential Timber Framed Construction (cyclonic areas)
ADCM Australian Domestic Construction Manual
BCA96 Uniform Building Code Of Australia
All timber framing and associated construction materials shall be the best of their type available for the nominated stress grades.
Standard specifications often include only basic general information about cupboard work. Many architects prefer to include comprehensive notes on the detail drawings. The specifications in this example were taken from joinery drawings for a large commercial construction project.
General Notes
Cupboards And Benchtops
Open Shelving
General Notes – Fixed Furniture
Example 6 - Brick/Blocklayer
The mortar mix is to conform to the latest edition of AS3700 class M3 or M4. Typical mix consistencies are as follows:
M3 - 1 x Cement 1 x Lime 6 x Sand
M4 - 1 x Cement 0.5 x Lime 4.5 x Sand
Mortar joints should be not more than 10mm thick.
Raked joints should be less than 3mm deep and have a tooled finish.
Mortar must not contain organic material or have any visible defects.
Bricks are to be laid with full perpends and mortar bed.
All brickwork should be cleaned progressively during laying.
The damp proof course should be installed below the floor slab level.
All openings should be caulked to seal any gaps between brick or blockwork and timber framing.
Sill and sash bricks/blocks should be laid on full mortar beds using full perpends.
Before leaving this page, think of what you've just been reading, and test yourself with these questions.
[[ mr /f ][ Which of these trade areas would typically not be included in building specifications? ][ * Concretor ][ Soft Furnishings ][ * Tiler ][ Whitegoods Supplier ][ * Masonry ][ * Floor Coverer ][ Soft furnishings and whitegoods aren't considered part of the building process - all the others are. ]]
[[ mm /5 /f ][ Match the following specifications to the work / trade area that they relate to: ][ Siteworks ~ The degree of compaction is to be verified ... ][ Painter ~ Use filler tinted to match the substrate ... ][ Concretor ~ Lap all reinforcement bars as follows ... ][ Carpenter ~ BCA96 Uniform Building Code of Australia ][ Joiner ~ Interiors - 16 MHR Aquabond White ][ Bricklayer ~ Raked joints should be less than 3mm deep ][ Siteworks => degree of compaction; Painter => tinted filler; Concretor => reinforcement bars; Carpenter => BCA96; Joiner => interiors; Bricklayer =>raked joints. ]]