Concrete Raft Slab Guide - Design, Cost and Construction

Concrete Raft Slab

What is a raft slab and how does it compare to waffle pod slabs? In this post, we examine the design, cost, construction and benefits of a raft foundation.

Request a Free Measure & Quote

Complete the form below and we’ll arrange a free quote with a Masta Concrete expert.

    SERVICES

    Concrete Raft Slab Guide: Design, Cost and Construction

    If your new home construction requires a raft slab design for its foundation, would you know what was required? How is this concrete slab constructed? And how does this type of slab compare to other concrete slabs? 

    In this post, we are going to look at just that. We will look at raft slab design, construction, costs and other associated benefits.  

    Let’s begin by looking at what a raft slab is. 

    foreman spreading sub base, preparing a site for concrete raft slab foundation

    Call On The Experts

    If you need high quality concreting services in Sydney or beyond, we'd love to provide the expertise, design and installation for your project! Contact us today to discuss your concreting needs and get a free estimate.

    Concrete Raft Slab Design

    The basic design of a raft slab is a concrete slab that is built onsite and strengthened by concrete beams spanning both directions. This type of slab is used in new home construction as well as extensions added to your home. 

    Raft slabs constructed in Australia comply with Australian Standard AS 2870. The beams that strengthen these slabs are the perimeter footing beams and the strip footing that run parallel to the slab itself. 

    The slab can vary in thickness from a minimum of 85mm (3.35 inches) to a maximum of 150mm (8 inches thick) depending on structure requirements. The perimeter footings and strip beams will vary in depth according to the particular set of characteristics the soil around the footing comprises. This strip footing design is also done in accordance with AS 2870. 

    That’s how a raft foundation slab is designed. Now, let’s look at how it is constructed. 

    Concrete Raft Slab Construction 

    Once the surveying equipment has determined the exact location of the home, perimeter footing can then be excavated. These footers can vary in size depending on soil conditions, but all footers start out at a minimum of 300mm (16 inches) wide. Then, reinforcing steel rods are added according to specifications and the concrete footings are then poured. 

    Once these footers have cured, a damp-proof membrane, granite or other supporting medium is added to the area where the ‘raft’ will be within the confines of the perimeter footing. Once these support mediums are sufficiently compacted and the steel reinforcements are added, the actual ‘raft’ of concrete can be poured inside the walls of the footers. 

    When needed, additives can be added to the concrete in the ‘raft’ so that it cures at the same rate as the footer. The actual curing time is 23 to 28 days. 

    Your Free Consultation

    Get fixed pricing and guaranteed workmanship, book us today to discuss your concreting project and get a free estimate.

    Concrete Raft Slab Cost 

    In a nutshell, the choice of slabs for your construction project comes down to a matter of requirements. Certain types of soil and other specifications may prevent you from choosing waffle pod slabs that tend to be a bit cheaper to produce. 

    That being said, raft slabs are chosen by far more contractors as the ‘slab of choice’ as the raft design tends to be more forgiving for contractors and designers alike. 

    The amount of concrete that makes up this slab design is quite a bit more than that required of its waffle pod slab counterpart. 

     

    Concrete Raft Slab Benefits 

    If the area under and around your home is subject to erosion, waffle pod slabs offer little protection in that event. Raft slabs are more efficient where areas of high erosion are commonplace. 

    Also, the raft slab design is cast against the ground itself whereas a waffle pod slab is cast around the polystyrene formers. If your slabs are overloaded, they are less likely to crack because they are cast against the ground. 

    Raft slabs are also a more favorable option if there is to be any type of gardening or landscaping that comes right up next to the house. 

    These are the basics of raft slab design and some benefits that are only found in that design. 

    HAPPY CUSTOMERS

    Our regular clients know our commitment to being available whenever we’re needed and reputation for high quality, reliable work. See what customers are saying about our Concrete Construction Company.

    

    Ali took care of the project, explaining the process and was super clear in terms of timeline and finished product. Ali and his boys did our foundation and suspended slab work internal support and car parks/driveways. Awesome bloke to deal with.

    CREWFIT

    Ali from Masta Concrete was very professional in all aspects of the job. The whole job run very smoothly and an outstanding product was delivered. Sometimes it can be daunting finding good, reliable tradesmen but when we found Ali it took all our worry away.

    Mark A Mello

    We are owner builders and got in touch with Masta Concrete to do our concrete slab and foundations for our new house build. They did a great job and all ways kept us informed of what was happening at each stage. They organised the engineering inspections and the whole job went smoothly. We highly recommend Masta Concrete.

    Naime Mustafa

    AREAS WE SERVICE

    When you need professional concreting services Sydney wide and across regional NSW, Masta Concrete has you covered.

    See our service area page for more details or contact us now.

    Metropolitian Sydney

    Wollongong

    Southern Highlands

    Penrith & Richmond

    Blue Mountains

    Sutherland Shire

    WHAT WE DO

    Our Services

    We cover all aspects of Formworks, Concreting and Excavation

    concrete driveway sydney banner

    CONCRETE SLABS

    Masta Concrete installs high-quality Concrete & Cement Slab Foundation all over Sydney, NSW. Request a free quote for Concrete Slabs installation now.

    concrete house slab construction sydney

    CONCRETE HOUSE SLABS

    Masta Concrete installs high-quality Concrete & Cement Slab in Sydney. Check out for Cost Of Concrete Slab Construction for your House now.

    concrete suspended slabs banner

    CONCRETE SUSPENDED SLABS

    Masta Concrete is a Sydney based company that specialises in Concrete Suspended Slabs, Footings, Steel Fixing & Excavations. Request for a free quote now.

    concrete basement construction banner

    CONCRETE SLAB FOOTING

    Masta Concrete installs high-quality Concrete Slab & Pad Footing all over Sydney, NSW. Request a free quote for all kinds of Concreting Services now.

    concrete basement construction banner

    CONCRETE BASEMENTS

    Masta Concrete most renowned Concrete Basement Construction Company in Sydney. Request a Free Measure & Quote for strong Concrete Basement Floor.

    WHY WORK WITH US

    We have the knowledge and experience to complete all types and sizes of concrete construction projects. We are fully licensed and insured and are committed to jobsite safety and practicing safe work methods.

    Contact us to estimate your next concrete project and learn why we are Sydney’s top concrete contractor!

    sydney concreting
    1 We have the knowledge and experience to complete all types of concrete construction projects from small to large.
    2 We are fully licensed and insured.
    3 We are committed and focused on practicing safe work methods.
    10Industry

    Experience

    142Completed

    Projects

    96%                    Happy

    Clients

    %

    Request a Free Measure & Quote

    Complete the form below and we’ll arrange a free quote with a Masta Concrete expert.

      Subscribe for a Newsletter

        WELCOME TO MASTA CONCRETE

        Masta Concrete is a Concrete Construction Company based in Sydney. We cover all aspects of concreting works including Excavation, Formwork, Steelfixing and Concreting. We are committed to and believe in delivering every project safely, on time and within the project budget. We are the leading concreters in Sydney and are reputed as one of the best concrete construction companies in Sydney.

        ENQUIRE NOW

        Fill the form below and we'll arrange a free quote with a Masta Concrete Expert

          © Copyright 2021 Masta Concrete

          Previous Next
          Close
          Test Caption
          Test Description goes like this