Create a new basement without rebuilding everything. Aldig provides expert retrofit basement solutions for difficult sites with limited access across Melbourne and Victoria.
We specialise in projects where families continue living on-site, using methods that minimise disruption and keep your home safe and accessible throughout construction.
Create a new basement without rebuilding everything. Aldig provides expert retrofit basement solutions for difficult sites with limited access across Melbourne and Victoria.
We specialise in projects where families continue living on-site, using methods that minimise disruption and keep your home safe and accessible throughout construction. Our tailored approach means your needs are considered at every step, giving homeowners peace of mind and a smoother renovation process.
Building a basement under or beside an existing property has different challenges compared to building on a cleared site.
The existing building must stay supported while digging, which often happens in small spaces close to other properties. We also check foundations, underground utilities, building weight, and site access before starting work.
With more than 20 years of experience in complex basement and structural projects, Aldig delivers retrofit basement solutions designed for each property.
A successful retrofit basement project begins with a clear understanding of the current property and how to do the work safely and realistically.
Aldig reviews building designs, engineering plans, soil reports, and site conditions to identify the main construction requirements.
Planning early helps spot risks with structure, access, and work order before starting. This makes building easier and gives everyone a clearer idea of what is needed.
Underpinning might be needed when digging goes below or near the base of an existing building.
Underpinning supports the existing building and safely carries its weight while digging and basement building happen below or next to it.
This step-by-step approach helps control movement, keep the site stable, and reduce risks to the building and nearby structures.
Temporary support systems hold up the surrounding ground and buildings while digging and permanent basement work are done.
The appropriate retention solution depends on the excavation depth, ground conditions, property boundaries, neighbouring buildings and available working space.
Combining these steps in one plan helps avoid gaps between workers and keeps the project moving smoothly.
Many retrofit basement projects are on existing properties where regular digging equipment cannot easily reach the work area.
Aldig plans digging and dirt removal based on the space available and support needs. Small machines, conveyors, and step-by-step material handling may be used where access is tight.
Digging is done in steps and coordinated with underpinning, temporary support, and props. This careful order keeps the site steady while building the basement.
Building a basement under an existing property may need changes to the original building structure.
These tasks must be carefully scheduled with underpinning, temporary support, and digging stages.
Aldig works with project engineers and consultants to complete structural changes according to the approved plans and construction methods.
Once digging and temporary support work are underway, Aldig can build the permanent basement structure.
Our team focuses on precise layout, placing reinforcements, concrete work, and connecting the new and existing structures.
Careful sequencing helps ensure a smooth transition from temporary support systems to the permanent basement structure.
The finished structural shell can then be prepared for waterproofing, utilities, interior work, and the next project stages.
It’s important to plan waterproofing early in a retrofit basement project because membrane systems often must be installed during building.
The specific waterproofing solution will depend on the basement design, ground conditions, groundwater considerations and project documentation.
For added peace of mind, our waterproofing installations come with a warranty that covers materials and workmanship, helping to safeguard your new basement against water ingress. Warranty terms and coverage details can be discussed and confirmed as part of your project plan.
Retrofit basement construction introduces structural, excavation and access challenges that are not typically present on an open site.
The existing property may stay above or next to the work area while digging happens. Nearby buildings, utilities, boundaries, and occupied spaces can also limit access and affect how the work is done.
Aldig brings all key structural and excavation work together under one clear, specialist scope.
Aldig handles the structural support, temporary holding, digging, and permanent basement work needed for a retrofit basement project.
Having one skilled team manage all these steps can:
This method gives you a clear path from the existing building and temporary supports to the finished basement structure.
Aldig uses a structured approach to plan and deliver retrofit basement projects throughout Melbourne and Victoria.
We start by reviewing the existing property, the planned basement design, site conditions, and any construction constraints.
From there, we work with the client and project consultants to develop a practical scope and plan for structural support, excavation, logistics, and permanent basement construction.
Aldig delivers reliable piling and foundation systems for high-end homes and multi-unit builds. We design and install cost-effective residential piles and foundations that meet Australian Standards and builder timelines.
Aldig specialises in delivering high-quality piling, foundations and underpinning for residential renovations across Melbourne. Whether you're extending, adding a basement, or strengthening an existing structure, our team provides safe, reliable solutions tailored to your site conditions.
Aldig provide high-capacity piling and foundation solutions for childcares, car parks, medical centres, retail, and mixed-use developments. Our systems handle complex loads and tight urban sites with precision, safety, and efficiency.
With years of proven results in Melbourne’s basement and concrete structure construction, Aldig brings expertise, quality and reliability to every project.
Backed by experience, Aldig uses proven data and costing models to ensure your project is accurately costed—minimising the risk of costly blowouts.
Our team specialises in overcoming challenging sites, tight access, and complex builds—using our own specialised equipment and in-house experience to deliver quality results.
Aldig is an accredited and fully insured waterproofing contractor, committed to quality and compliance.
Feedback from our clients highlights the care, coordination and technical skill behind Aldig’s basement and structural concrete projects. These testimonials reflect real experiences from homeowners, builders and developers who have trusted Aldig with complex excavation support and retention works across Melbourne and Victoria. Their words speak to our commitment to practical problem-solving, clear communication, safe site preparation, and reliable delivery from planning through to site works.
The cost of a retrofit basement varies significantly because every project involves different structural, excavation and access requirements. Key cost factors include the basement size and depth, existing foundation conditions, ground and groundwater conditions, underpinning requirements, temporary retention, site access, spoil removal, structural alterations, waterproofing and the level of internal fit-out required.
Projects beneath existing buildings generally require more specialised planning and construction than basements built on cleared sites. Aldig can review the available drawings, engineering information and site conditions to help define the required scope and provide more accurate project pricing.
The timeline depends on the size and complexity of the basement, the condition of the existing structure, site access, engineering requirements and the approvals needed before construction can begin.
A retrofit basement is normally completed in carefully controlled stages, including structural support, temporary retention, excavation, spoil removal, permanent concrete construction and waterproofing. Restricted-access sites or projects requiring extensive underpinning and structural alterations may take longer.
A more reliable construction timeframe can be developed once the design, site conditions and proposed scope have been reviewed.
Whether you can remain in the property will depend on the location of the works, the structural methodology, access arrangements and the level of disruption involved.
Retrofit basement construction can create noise, vibration, dust, machinery movement and temporary changes to access or services. In some cases, sections of the property may remain usable, while more complex projects may require the building to be temporarily vacated during critical construction stages.
Aldig considers occupied areas, site access and work-zone requirements when planning the project. Any expected disruptions and occupancy restrictions should be discussed before construction begins so appropriate arrangements can be made.
Retrofit basement projects commonly require architectural and structural documentation, a building permit and approvals relevant to excavation, structural alterations and the proposed use of the basement. Depending on the property and project, planning approval, protection work documentation, asset protection permits or additional council requirements may also apply.
The specific approvals will depend on the local council, property conditions and project design. Aldig works with clients, builders, engineers, architects and other consultants to ensure the construction scope aligns with the approved documentation. The responsibility for obtaining permits and approvals should be clearly confirmed during the planning and proposal stage.
Applicable warranties and guarantees depend on the agreed contract, scope of work, materials and waterproofing system selected for the project.
Structural work should be completed in accordance with the approved engineering documentation and agreed construction requirements. Waterproofing products may also include manufacturer warranties, subject to correct specification, installation and ongoing compliance with the manufacturer’s conditions.
As certified and insured CETCO waterproofing membrane installers, Aldig can coordinate eligible waterproofing systems with the basement construction. The specific workmanship warranties, product warranties, exclusions and maintenance requirements should be confirmed in the project proposal and contract before work begins.
Work with Aldig to create a retrofit basement solution that matches your property, basement design, and construction needs.
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