BCGBC4007A Plan building or construction work

Organise materials

Timber calculations for framing a house
Step 1
Top plate length = total of lengths along the long wall of the second bedroom (include the 90 mm thickness of the timber at each corner). 
Length of top plate: 90 + 910 + 2500 + 90 = 3590 mm
Multiply by 2 to include the length of the bottom plate. 
Total length of top and bottom plates: 3590 x 2 = 7180 mm
Divide by 1000 to convert to metres: 7180 ÷ 1000 = 7.180 m

Question 1
What is the total length of the top and bottom plates of the short wall in the second bedroom?
A.     	2.500 m
B.     	2.680 m
C.     	5.000 m
D.     	5.360 m
The correct answer is D - 5.360 m. To obtain this answer, add 2500, 90 and 90, multiply by 2 and convert to metres. The total wall length is 2.680 m, multiplied by 2 which gives 5.360 m.
Step 2
The length of timber for the noggings is the same as for the top plate.
Length of noggings is 3590 mm = 3.590 m

Question 2
What is the length of noggings required for the short wall of the second bedroom?
A.     	2.500 m
B.     	2.590 m
C.     	2.680 m
D.     	2.770 m
The correct answer is C - 2.680 m. It's the same as the top plate length.
Step 3
Studs are positioned every 450 mm or less, depending on the length of the wall.
Long wall = 3590 mm with studs at a spacing of 450 mm.
3590 ÷ 450 = 7.98 rounded to 8
This gives 8 spaces and 9 studs. 
A diagram shows a plan of a room with positions of studs marked along the longer wall. There are double studs at each end of the wall, with 9 studs altogether and 
8 spaces in between, spaced out equally along the longer wall.
The corners use double studs giving 9 + 2 = 11 studs total.
Assume a ceiling height of 2.400 m.
This gives a total stud length of 11 x 2.400 = 26.400 m.
Question 3
How many studs do you need for the short wall of the second bedroom?
A.     	6
B.     	7
C.     	8
D.     	9
The correct answer is D (9). 2680 ÷ 450 gives 6 spaces and 7 studs plus 2 for the corners to give 9.
Step 4
As you will need to calculate the length of the window lintel in the frame for the topic activity, the method is given here. Measure the window on the plan in millimetres.
Window measures 9 mm.
Use the scale of 1:100 to convert: 9 x 100 = 900 mm.
Add 150 mm to each end of the lintel: 900 + 150 + 150 = 1200 mm.
Convert to metres: 1200 ÷ 1000 = 1.200 m.

Question 4
What length of timber lintel (in metres) would you need for the largest bedroom in this house?
A.     	1.900 m
B.     	2.050 m
C.     	2.200 m
D.     	2.350 m
The correct answer is C - 2.200 m. The window is 1900 mm plus the 150 mm x 2 to give 2.200 m.
Step 5
Working out the cost of these materials to frame the long wall is the final step in the process.
Top and bottom plates 90 x 45 mm MGP 10 pine $2.65 per lineal metre.
Noggings 90 x 35 merch pine $1.15 per lineal metre.
Studs 90 x 35 MGP 10 pine $1.95 per lineal metre.
Lintel 190 x 45 F17 $8.75.
Material cost calculations:
Plates: 7.180 m @ $2.65 per lineal metre = 7.18 x 2.65 = $19.03
Noggings: 3.590 m @ $1.15 per lineal metre = 3.590 x 1.15 = $4.13
Studs: 26.4 m @ $1.95 per lineal metre = 26.4 x 1.95 = $51.48
Total cost to frame the long wall of the second bedroom = $76.64
Note: The cost of the lintel is not included in this wall. Use the same method.
Lintel: 1.200 m @ $8.75 = $10.50
Question 5
What is the cost to frame the short wall of the second bedroom? Include the cost of the lintel in your calculation.
A.     $69.90
B.     $59.40
C.     $66.82
D.     $76.64
The correct answer is A - $69.90. Plates = $14.20, noggings = $3.08, studs = $42.12, lintel = $10.50 Total cost = $69.90

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