UNIT CONVERTER
Measurements, waste factors and conversions
Despite EU regulations the
building and timber trades continue to use a combination
of imperial and metric measurements. This can be a
little confusing, but worse, can lead to some drastic
calculation errors.
To make life simple try to use one
or the other and stick to it.
For imperial we use inches (“),
feet (‘), cubic feet (ft3) and square feet (ft2).
For metric we use millimetres (mm), metres (mt), cubic
metres (m3) and square metres (m2).
The timber trade does not tend to use centimetres.
Wood is sold in variety of ways:
- Rough sawn wood is normally sold
by the cubic volume (ft3 or m3)
- Machined sections are normally
sold by the running length (ft or mt)
- Flooring and some cladding
is normally sold by the square area (ft2 or m2).
 Feet
to metres |
x
by 3.281 |
| Cubic
feet to cubic metres |
x
by 35.315 |
| Square
feet to square metres |
x
by 10.76 |
ROUGH CONVERSION TABLE
| |
1 METER |
1 FOOT |
1 INCH |
1 CM |
| METERS |
1 |
0.305 |
0.025 |
0.01 |
| INCHES |
39.37 |
12 |
1 |
0.394 |
| FEET |
3.281 |
1 |
0.083 |
0.033 |
| MM |
1000 |
304.8 |
25.4 |
10 |
| CM |
100 |
30.48 |
2.54 |
1 |
METRIC - IMPERIAL CONVERSIONS
COMMON CONVERSIONS
Metric
to Imperial |
Imperial
to Metric |
To convert millimetres (mm) to
inches (in), multiply by 0.039.
Example: 380 mm x 0.039 => 15 in
|
To convert inches (in) to centimetres
(cm) to, multiply by 2.54.
Example: 17 in x 2.54
=> 43 cm
|
To convert square metres (m2) to
square feet (ft2), multiply by 10.764
Example: 40 m2 x 10.764
=> 430 ft2
|
To convert square feet (ft2)
to square metres (m2), multiply by 0.093
Example: 180 ft2 x 0.093
=> 16.7 m2
|
To convert cubic metres (m3) to
cubic yards (yd3), multiply by 1.308
Example: 20 m3 x 1.308 =>
26 yd3
|
To convert cubic yards (yd3)
to cubic metres (m3), multiply by 0.765
Example: 20 yd3 x 0.765
=> 15 m3
|
To convert cubic metres (m3) to
cubic feet (ft3), multiply by 35.315.
Example: 2 m3 x 35.315 =>
71 m3
|
To convert cubic feet (ft3)
to cubic metres (m3), multiply by 0.028
Example: 200 ft3 x 0.028
=> 5.6 m3
|
To convert kilograms (kg) to pounds
(lbs), multiply by 2.205
Example:
25 kg x 2.205 => 55 lbs
|
To convert pounds (lbs) to grams
(gm), multiply by 454
Example: 2 lbs x 454 =
908 grams
|
An imperial ton is approximately the same as
a metric tonne. A more accurate conversion is:
|
| To convert tonnes (1000kg) to tons,
multiply by 0.984 |
To convert tons to tonnes (equals
1000kg), multiply by 1.016
|
To convert litres (l or ltr)to
gallons (gall), multiply by 0.22
Example:
25 litres x 0.22 => 5.5 galls
|
To convert gallons (gall) to
litres (l), multiply by 4.544
Example: 50 galls x 4.544
=> 227 litres
|
TIMBER PRODUCTS: METRIC
- IMPERIAL CONVERSIONS
Timber products are imported or manufactured in metric
dimensions and unless specifically requested otherwise,
they will usually be available in a size close to
the 'old' imperial equivalent. The most common dimensions
are summarised below.
TIMBER LENGTHS
Standard timber lengths are:
|
Metric
length
(metres)
|
Imperial
length
(to nearest 1/16 in)
|
Approx
Equiv
Size in Feet
|
0.9 |
2 ft 11 7/16
ins |
3 ft |
1.2 |
3 ft 11 1/4 ins |
4 ft |
1.5 |
4 ft 11 1/16 ins |
5 ft |
1.8 |
5 ft 10 7/8 ins |
6 ft |
2.1 |
6 ft 10 11/16 ins |
7 ft |
2.4 |
7 ft 10 1/ 2 ins |
8 ft |
2.7 |
8 ft 10 5/16 ins |
9 ft |
3.0 |
9 ft 10 1/8 ins |
10 ft |
3.3 |
10 ft 9 15/16 ins |
11 ft |
3.6 |
11 ft 9 3/4 ins |
12 ft |
3.9 |
12 ft 9 9/16 ins |
13 ft |
4.2 |
13 ft 9 1/4 ins |
14ft |
4.5 |
14 ft 9 1/8 ins |
15 ft |
4.8 |
15 ft 8 15/16 ins |
16 ft |
5.1 |
16 ft 8 3/4 ins |
17 ft |
5.4 |
17 ft 8 9/16 ins |
18 ft |
5.7 |
18 ft 8 3/8 ins |
19 ft |
6.0 |
19 ft 8 3/16 ins |
20 ft |
6.3 |
20 ft 8 ins |
21 ft |
6.6 |
21 ft 7 13/16 ins |
22 ft |
6.9 |
22 ft 7 5/8 ins |
23 ft |
7.2 |
23 ft 7 7/16 ins |
24 ft |
Longer lengths may be available to
special order.
TIMBER SIZES
All timber sections are quoted in 'nominal' sizes
- the actual size of sawn timber or the size of a
machined timber section before any planning
or moulding. The actual 'finished' sizes
of machined timber will be 4-6mm less
than those listed.
For example:
50x100 mm planed timber (PAR) will be approximately
45x95mm actual size
19x75 mm planed timber (PAR) will be approximately
15x70mm actual size
Common timber sections are
|
Metric Size
(mm)
|
Imperial
size
(Inches)
|
Approx Equiv
Size in Inches
|
12 |
0.472 |
1/2 in |
13 |
0.512 |
1/2 in |
16 |
0.630 |
5/8 in |
18 |
0.709 |
3/4 in |
19 |
0.748 |
3/4 in |
22 |
0.866 |
7/8 in |
25 |
0.984 |
1 in |
32 |
1.260 |
1 1/4 in |
38 |
1.496 |
1 1/2 in |
44 |
1.732 |
1 3/4 in |
47 |
1.850 |
1 7/8 in |
50 |
1.969 |
2 in |
57 |
2.244 |
2 1/4 in |
63 |
2.480 |
2 1/2 in |
75 |
2.953 |
3 in |
85 |
3.346 |
3 5/16 in |
88 |
3.465 |
3 1/2 in |
100 |
3.937 |
4 in |
115 |
4.528 |
4 1/2 in |
125 |
4.921 |
5 in |
138 |
5.433 |
5 1/2 in |
150 |
5.906 |
6 in |
175 |
6.890 |
7 in |
200 |
7.874 |
8 in |
225 |
8.858 |
9 in |
250 |
9.843 |
10 in |
275 |
10.827 |
11 in |
300 |
11.811 |
12 in |
|
