ENGINEERING CERTAINTY. DELIVERED.
Extending your home can create the extra space you need without leaving the property and location you already enjoy.
But an extension also changes the existing building. New walls, roofs, openings and foundations need to integrate with the original structure while satisfying the applicable planning and building requirements.
Engineering On Demand provides complete Home Extension Approval Perth support, helping homeowners, builders and designers coordinate extension plans, structural engineering and approval documentation before construction begins.
From a new bedroom or living area through to major ground-floor and second-storey additions, we can help establish the approval pathway and prepare the technical information required to move your project forward.
Most substantial residential extensions involve building approval because they create new building work or alter the existing dwelling.
WA local-government guidance identifies residential additions and alterations among the types of work for which Building Permits are usually required. Development Approval is a separate consideration and may also be required depending on how the proposed extension responds to the property’s planning controls.
The important part is establishing the correct pathway before the extension is built.
Engineering On Demand can review the proposed works, identify the technical information required and coordinate the structural engineering and drawings needed to support the applicable approval process.
WA Building & Energy — Building Approvals
Designed for WA requirements.
Familiar with WA approval requirements.
Designs that work with the existing home.
A House Extension Approval Perth project can involve more than one approval pathway.
The Building Permit process deals with the proposed building work and compliance with applicable building standards.
Planning requirements deal with how the development relates to the property and surrounding area. The WA R-Codes address matters including lot-boundary setbacks, building height, site cover, streetscape, landscaping and visual privacy.
A project can therefore require a Building Permit without requiring Development Approval, while another extension may require both.
Establishing this early can prevent the architectural and engineering documentation from being developed around a design that later needs significant changes.
Before designing the extension, we need to understand how the existing home is constructed and how the proposed works will interact with it.
Additional roof, floor and wall loads need a clear structural path through the building and into suitable foundations.
Creating larger openings between the existing home and new extension may require load-bearing walls to be removed and replaced with engineered beams or other structural support.
New foundations need to suit the proposed extension, site conditions and structural loads while appropriately interfacing with the existing building.
The new roof structure needs to work structurally and practically with the existing roof, including loads, connections and changes in roof geometry.
Upper-floor extensions introduce additional loads and may require assessment or strengthening of the structure below.
A Building Permit should not be treated as paperwork to sort out once construction is ready to begin.
The architectural plans, structural engineering and other supporting documents need to work together so the proposed extension can be assessed as a coordinated project.
For significant residential additions and alterations, that can mean resolving structural openings, new foundations, roof alterations and connections between old and new construction before the permit documentation is completed.
Engineering On Demand can assist with the engineering and documentation required to support your Extension Permit Perth application.
A Building Permit deals with the proposed building work and the applicable building standards.
For a home extension, the supporting information can include architectural drawings, structural engineering, specifications, energy-efficiency information and other project-specific documentation.
WA’s building approval system includes prescribed permits, certificates and forms under the Building Act and Building Regulations.
Development Approval is separate from the Building Permit.
An extension may need to be assessed against applicable planning requirements relating to matters such as setbacks, building height, site cover, privacy and the relationship between the development and surrounding properties.
Where a proposal doesn’t satisfy the applicable deemed-to-comply requirements, an alternative planning assessment pathway may be necessary.
YOU MAY NEED BOTH — Development Approval and a Building Permit are separate processes. The approval pathway should be established before the extension design is finalised.
Ground-floor extensions can add bedrooms, living areas, kitchens, bathrooms and other usable space.
The new construction needs to connect properly with the existing dwelling while the foundations, walls and roof are designed for the proposed loads and site conditions.
Building upward can make better use of constrained sites, but it introduces loads into a structure that may never have been designed to support another storey.
Existing walls, beams, footings and other structural elements may therefore need to be assessed before the upper-floor structure is designed.
Modern extensions frequently create large openings between the original house and the new living area.
Where an existing load-bearing wall is affected, a structural engineer can determine the required replacement beam, supports, connections and load path.
This is a natural internal link to your Load Bearing Wall Removal Perth page.
An extension can require substantial changes to the existing roof.
The engineering needs to consider how the new roof is supported, how it connects with the original building and whether alterations to existing trusses, rafters or supporting walls are required.
Extensions are often proposed because homeowners want to maximise the usable area of an existing property.
That makes setbacks and boundary relationships particularly important.
Current WA planning controls include requirements dealing with lot-boundary setbacks and amenity considerations.
Removing a structural wall isn’t simply cosmetic renovation work.
Schedule 4 of the WA Building Regulations excludes work involving removal or alteration of an element supporting another building element from the relevant renovation/alteration permit exemption.
The replacement structural support should therefore be properly assessed and designed before demolition.
Structural engineering can include foundations, slabs, framing, beams, lintels, columns, roof structures, bracing and connections.
The exact scope depends on the existing home and the proposed extension.
The architectural design and structural engineering need to tell the same story.
Coordinating them before approval reduces discrepancies between architectural drawings, structural drawings and the construction documentation used on site.
Where an extension has already been constructed without the required approval, the pathway is different from obtaining approval before construction.
Existing work may require measured drawings, structural inspection, engineering assessment and other supporting evidence depending on the circumstances.
The appropriate retrospective approval pathway should be established for the particular building and local government.
Substantial residential additions and alterations will generally involve building approval. Development Approval is a separate planning consideration and depends on the particular proposal and property.
Building Permits are usually required for residential additions and alterations. The precise requirements should be confirmed for the particular work.
Not necessarily. This depends on how the proposed extension responds to the applicable planning framework and any relevant local planning requirements.
No. They are separate processes. Planning assessment considers the development against applicable planning requirements, while the building approval process addresses the proposed building work and applicable building standards.
A structural engineer can design the structural elements required for the extension, including foundations, slabs, beams, columns, framing, roof structures and connections, depending on the project.
Yes. Engineering On Demand can assist with the engineering, drawings and technical documentation required for the agreed approval scope.
Yes. Where structural steel is required, engineering can determine the appropriate beam, column and connection requirements for the proposed structural arrangement.
Potentially, but the existing loads need to be assessed and replacement structural support designed. The relevant Schedule 4 exemption does not cover removal or alteration of a building element that supports another element.
Potentially. The existing building needs to be considered because the additional storey can introduce significant new loads into existing walls, beams and foundations.
That cannot be assumed. The existing structure and foundation system need to be assessed in relation to the proposed additional loads.
It depends on the proposed work and information already available. New foundation design may require appropriate information about the site’s foundation conditions.
Potentially, but the proposal needs to address the applicable planning and building requirements. Lot-boundary setbacks are specifically addressed by the WA R-Codes.
There are approval pathways for existing buildings and unauthorised work, but the required documentation and assessment depend on the circumstances. WA’s building approval framework includes Building Approval Certificates for existing buildings.