Designing a Deck for Six People

The task required is to design and measure out the costs for both a simple and complex deck using a range of 2D shapes to help generate the central idea. The client has specifically outlined that they request a decking area that would comfortably seat six people. The two option that will explored are limited to a $8000 budget, which includes all materials and labour costs (estimate, no need for calculation) that are required in order to construct both decks. When considering the shapes to involve within both designs, it is evident that rectangles and semi circles have been utilised in order to create the form of these decking plans. Materials involved include back plate, bearers, posts, joists, decking, concrete mix, and paint, decking oil, dynabolts, nails and stirrup bucket. In order to quote the client as to how much each deck will cost, calculations and measurements will be priced up within the folio. Mention appendix in introduction, mention scale drawings, draft, and costs

M A T H E M A T I C A L  I N V E S T I G A T I O N S

P A R T O N E

A typical dining room table is 4 feet wide by 6 feet long with each chair at 2 ft. square. Calculations of the dining table dimensions take into account the clearance and the distance from the table to sit comfortably when the chair is pulled away. Clearance is defined as the distance between the edge of the table and the nearest piece of furniture or wall. The first design applies a rectangular table measuring 4-foot-by-6-foot. When a chair is pulled away from the table, the distance required to sit comfortably is estimated to be 1 foot. The clearance required to walk around a chair that is pulled away from the table is taken to be 2 feet. Therefore the total width and length of the table to comfortably sit six people is calculated as follows.

The second design is L-shaped, with each rectangle measuring 6ft long by 2ft wide. The same estimation is applied for clearance and distance when chair is pulled away from the table. This gives the following length and width calculations.

Part 2

Deck footings are concrete columns that support the deck.  Depth of the footings varies from one area to another depending on the frost depth and varying ground conditions. The National Construction Code of Australia outlines different soil types and performance requirements for certain soil properties. It is recommended to dig down until ground changes from soft to hard i.e. when solid ground is reached. However, whether or not solid ground is reached, a minimum depth of 600 mm is considered standard. An extra 50 mm should be dug into the solid ground.

Joists are structural components made of either steel or timber that offer support to the deck. They are usually arranged in parallel. Size of the joists is determined by the number of beams and footings to be installed i.e. the size of the deck. Joist spacing centre to centre is recommended to be 16 inches. A deck can be constructed at ground level or elevated to a certain height. Ground level decks are advantageous over elevated decks due to their ease of framing and no requirement for guardrails. They also do not require frost- depth footings. This makes them more cost effective. Nevertheless, the height of elevation is recommended to be 6”, 12”, and 24” etc. Typical height of 30 inches is recommended since above this height guardrails are recommended.

 Building a deck requires materials such as timber as the main structural component. Hardwoods such as cedar and redwood are recommended for wooden boards since they withstand changes due to sun and moisture exposure. Concrete is also required for the footings. Precured and shaped concrete piers may also be used for this. Fasteners are required to join the various components. They influence the safety of the structure as stress from the structure’s weight is concentrated on these. Some fasteners include screws, bolts, not nails, etc. screws are applicable in sections with minimal stress, for instance at a connection between a board and a joist. Brackets are used as metal support plates for the joists and other structural members mainly for safety purposes. T-shaped brackets and joist hangers are used in deck building.

 Part 3

The rectangular deck is 16 x 12 ft. the materials are costed per square foot. Other costs are considered in addition to the materials. These include painting, UV sealing, rails, stairs, waterproofing, labour etc.

qty

description

unit price

1

BACK PLATE – 572mm x 200mm

$11.99

2

BEARERS – 3600mm x 600mm x 16mm

$36.22 EACH

2 x $36.22

$72.44

6

POSTS – 90mm x 90mm x 1500mm

$102 EACH

6 x $102 =

$612

5

JOISTS -360mm x 58mm

$21 EACH

5 x $21 =

$105

14

DECKING – 70mm x 20mm (3m)

$6.90 EACH

14 x $6.90 =

$96.60

3

CONCRETE MIX – 20KG

$7.90 EACH

3 x $7.90 =

$23.70

5 LITRES

DECK OIL

$98.90

3

DYNABOLTS – ONE FOR EVERY 100MM (10CM)

$1.82 EACH

3 x $1.82 =

$5.46

15 LITRES

PAINT – LEFTOVER WILL USE IN DESIGN TWO

$164

Subtotal

$1190.09

The L-shaped deck measures 7ft by 18ft for section A and 7ft by 9 ft. for section B

qty

description

unit price

1

BACK PLATE – 572mm x 200mm

$11.99

2

BEARERS – 3600mm x 600mm x 16mm

$36.22 EACH

2 x $36.22

$72.44

8

POSTS – 90mm x 90mm x 1500mm

$102 EACH

8 x $102 =

$816

6

JOISTS -360mm x 58mm

$21 EACH

6 x $21 =

$126

14

DECKING – 70mm x 20mm (3m)

$6.90 EACH

14 x $6.90 =

$96.60

5

CONCRETE MIX – 20KG

$7.90 EACH

5 x $7.90 =

$39.5

5 LITRES

DECK OIL

$98.90

7

DYNABOLTS – ONE FOR EVERY 100MM (10CM)

$1.82 EACH

7x $1.82 =

$12.74

15 LITRES

PAINT – LEFTOVER WILL USE IN DESIGN TWO

$164

Subtotal

$1339.27

Discussion

The rectangular design whose total cost is $1190.09is more cost effective as it requires fewer structural components to support the deck. Cost of the L-shape is $1339.27. The L-shape, on the other hand requires almost twice as much support especially because of the corner. The L-shape also introduces angles which means that these two have to be considered during construction. Therefore, it is recommended that the rectangular design is applied.

ADD IN CALCULATIONS FROM APPENDIX TWO ONTO FOLIO

EXPLAIN CALCULATIONS

AREA = 2.5M X 3.0M = 7.5M SQAURED

Quote The Client Introduction: Design Number One

qty

description

unit price

1

BACK PLATE – 572mm x 200mm

$11.99

2

BEARERS – 3600mm x 600mm x 16mm

$36.22 EACH

2 x $36.22

$72.44

6

POSTS – 90mm x 90mm x 1500mm

$102 EACH

6 x $102 =

$612

5

JOISTS -360mm x 58mm

$21 EACH

5 x $21 =

$105

14

DECKING – 70mm x 20mm (3m)

$6.90 EACH

14 x $6.90 =

$96.60

3

CONCRETE MIX – 20KG

$7.90 EACH

3 x $7.90 =

$23.70

5 LITRES

DECK OIL

$98.90

3

DYNABOLTS – ONE FOR EVERY 100MM (10CM)

$1.82 EACH

3 x $1.82 =

$5.46

15 LITRES

PAINT – LEFTOVER WILL USE IN DESIGN TWO

$164

Subtotal

$1190.09