As part of the building process when the Architectural or Building Design plans are complete the Structural Design needs to be carried out.
The large majority of the structural design is unseen in the final home structure. The foundation is in the ground and under the floor coverings, the framing, lintels and beams are covered with wall sheeting, and wind bracing panels are quietly working doing their job when the wind blows without being seen.
Do not leave structural design to the inexperienced. Although the structural aspects are not seen they are extremely important for your safety and the durability of your home.
Soil Test
We always start with a soil test. The load of the house on the soil is significant but the forces the soil pushing up on the house can be even greater. It is when uneven forces due to differential moisture conditions occur, that the forces are at their greatest. Through these differential movements the soil tries to bend the house. The soil test allows a calculation to be made to give a numerical value of the movement in millimeters. The Australian Standard AS2870 provides classifications based on this differential movement.
Foundation Design
There are predominately two types of footing systems used in the foundation preparation.
- Conventional – which involves a steel reinforced concrete footing with a steel reinforced concrete slab.
- Waffle Slab – which involves a steel reinforced concrete slab with steel reinforced concrete stiffening beams, known as “stems” in a grid pattern.
For both systems, the type, size and amount of steel and concrete is based on the Soil Test Classification.
So as the soil moves the correctly designed foundation bridges over and smooths out the movement effects of the soil. The Structural Designer and Engineer are very aware of this aspect and they work together to create a foundation design that will work for your specific site soil materials and structure size and shape.
Our designs are RPEQ (Registered Professional Engineer of Queensland) reviewed & certified as required by Law by our third party Affiliate Engineer. So you can know that your foundation has been designed right.
Structural Design
This refers to the part of the structure above the foundation which may be made of many different types of materials.
We design the following items, however, the list is not exhaustive.
- Truss layouts
- Pitched roofs – rafters, hanging beams, pitching beams etc
- Timber framing – walls framing members, lintels, beams, posts, bearers & joists
- Wind bracing
- Tie-down to resist wind uplift forces
- Structural connections as required with drawn details. This is necessary to ensure that the builder is not left on site to guess any connections.
(C&A Doherty Building Consultants are not Registered Professional Engineers of Queensland by name or any other form, nor do we portray or imply this respected status. Complex designs are carried out where necessary under the direct supervision and review of our third party Affiliate Engineers with RPEQ status who we are the Sunshine Coast Representatives)
Effluent Design
If you are building in an area that is not serviced by the Local Authorities sewerage system you will require an on site effluent disposal system.
The process involves a number of stages-
- We investigate the on site soils in the area of the Land Application Area
- The soils found are categories to AS1547
- Information collected regarding the home then establishes the remainder of the design parameters
- An Effluent Disposal Concept is then calculated and documented for the client.
The report provided can then be used by any system supplier who supplies a system as noted in the provided report.