Advanced Structural
Designs ACN 097 789 87
92 Vasey Cres CAMPBELL ACT 2612 Telephone
61612171
Facsimile 61612170 Email mal@structuraldesigns.com.au
Flooring
Material spanning over joists
The most
critical loads for flooring systems spanning between joists are the point loads
that will be imposed on the floor system.
The point loads to be carried are codified in AS1170.1 and are applied
by a 100mm by 100mm pad load applicator.
Some typical
values are
|
Flooring Application |
Uniformly Distributed Load (kPa) |
Point Loads (kN) |
|
Residential |
1.5 |
1.8 |
|
Assembly Areas |
3-5* |
2.7-3.6 |
|
Public Corridors and spaces |
4-5 |
4.5* |
|
Stages |
7.5 |
4.5 |
|
Offices |
3.0 |
6.7 |
|
Retail Sales Areas |
5.0 |
7* |
|
General Storage |
2.4* /m ht |
7* |
|
Drill Rooms and Halls |
5.0 |
9* |
* Minimum requirement, maximum to be determined
When
looking to span a flooring material between joists the spacing between the
joists is the other critical factor.
Most manufacturers work out capacities based on solid supports such as
50 mm wide timber joists so if your joists are cold formed steel you should
decrease the joist spacing by 50 mm to allow for the top flange rotation under
load.
|
Material Type |
Sheet Thickness (mm) |
Joist Centres (mm) |
Max UDL (kPa) |
Loads (kN) |
|
|
15 |
450 |
4.4 |
2.7 |
|
|
15 |
400 |
5 |
3.2 |
|
|
18 |
600 |
4.8 |
3.0 |
|
Hardy’s FC |
18 |
450 |
6.4 |
4.5 |
|
|
18 |
400 |
7.2 |
5.4 |
|
|
24 |
600 |
8.6 |
6.8 |
|
|
24 |
400 |
12.8 |
12.4 |
|
Structafloor |
19 |
450 |
1.5 |
1.8 |
|
Particleboard |
22 |
600 |
1.5 |
1.8 |
|
Flooring |
25 |
600 |
3 |
? |
|
|
25 |
450 |
4 |
4 |
|
|
15 |
600 |
15 |
1.5 |
|
|
15 |
450 |
35 |
2.7 |
|
F22 Plywood |
19 |
600 |
35 |
3.0 |
|
|
19 |
450 |
63 |
5.3 |
|
|
25 |
600 |
48 |
8.0 |
|
|
25 |
450 |
75 |
14.2 |
If you need
advice on commercial tongue and groove strip flooring this is a little more
complicated as the flooring comes in 19, 25 and 30mm thicknesses, 5 different
strength grades and spacing varies depending on whether you butt joint over
joists (minimum width 50mm) or use end matched flooring profiles. This represents
a little more information than can be conveniently be presented in one table
but if you call us with the details of the species of timber you have selected
we will quickly establish the spacing.
It is also
possible to spread compactus loads, strengthen existing floors or use different
grades and thicknesses of plywood, so if you need further structural
engineering advice in Canberra ACT or
the surrounding district just give Mal Wilson
from Advanced Structural Designs a call on Ph 02 61612171