Frequently Asked Questions

Depending on the order size, HYBUILT can usually deliver your materials within 2 to 3 business days after order confirmation. Larger or staged orders can take longer, and if that is the case we will tell you when you order rather than on the day it was meant to arrive. Quotes normally come back within one business day, and the dispatch clock starts once the order is confirmed. See Delivery and Installation for the detail.

We do not publish delivery prices, because a flat rate would be wrong for almost every order. Freight depends on the load size, the distance from our Rocklea yard, the site access, the vehicle required and whether your load can be shared with another delivery. Send us your material list and the suburb or town the material is going to, and our team will confirm your freight cost along with stock availability before you are asked to pay anything.

We deliver to Brisbane, the Gold Coast, Ipswich, the Sunshine Coast and Toowoomba, across the region from Gympie to Kingaroy, and south to Lismore in Northern New South Wales. If you are outside those areas, ask us anyway. We can often still get there, and our team will tell you what is possible for your suburb.

Drainage gravel is delivery only. We supply and deliver gravel to your site and do not provide a pickup option for it. For other products, contact us before you make the trip so we can confirm what is possible for your order and have it ready. Pickup runs from 6am to 4pm, Monday to Friday, and we will email you when your order is ready to collect. Bring your order number and a vehicle rated for the load. We are at 28 Shettleston Street, Rocklea QLD 4106, on (07) 3716 0191.

Soil, mulch, manure, hay and mining and quarry materials are regulated fire ant carriers in Queensland, and quarry materials specifically include gravel, fines, sand and crusher dust. There are two fire ant biosecurity zones in South East Queensland and the National Fire Ant Eradication Program reviews and updates them monthly, so what applies to a particular load depends on where the material came from, where it is going, and the zones on the day.

Two points that matter to you as the buyer. First, within a zone regulated material may be moved if it is moved within 24 hours of delivery, or the required storage or disturbance steps are followed, or it goes straight to an approved waste facility, which means if you stockpile delivered gravel or soil on site for longer than 24 hours those requirements and the record keeping become yours. Second, moving soil or quarry material out of the zones, or from Zone 2 into Zone 1, is prohibited unless a biosecurity instrument permit has been granted.

The program's advice to buyers is to ask the seller whether the material has been produced and stored in accordance with the regulation. Ask us, we would rather you did. Check the current position yourself at fireants.org.au on the day you order. Northern New South Wales operates its own separate emergency order for material coming from Queensland. There is more on this on our Delivery and Installation page.

Often yes, and you need to confirm it with your council or a licensed private building certifier rather than relying on a supplier.

Across much of South East Queensland the commonly applied trigger is one metre. Councils including Brisbane, Logan, Moreton Bay, Ipswich and the Gold Coast generally do not require building approval where all of the following are true: the total height of the wall and of the fill or cut it retains is no more than one metre above the wall's natural ground surface; there is no surcharge loading over the zone of influence, meaning nothing loading the ground behind the wall such as a driveway, a slab, a structure or another wall; the wall is no closer than 1.5 m to a building or another retaining wall; and it does not form part of the fencing for a pool. Individual councils add their own conditions, for example the Gold Coast also looks at combined wall and fence height under 2.0 m, walls over services, easement and covenant areas, and waterfront setbacks. The state level acceptable solutions behind these council positions sit in the Queensland Development Code NMP 1.7.

This is not a universal rule. Sunshine Coast Council is stricter, requiring a building permit before the construction, modification or repair of most retaining walls regardless of height, and council approval as a concurrence agency for walls over 2 metres. Thresholds and conditions vary between councils and are revised over time, and building approval is a separate process to planning approval, a siting variation, or amenity and aesthetics approval. Height alone does not settle it either, since easements, services, overlays, pool fencing and proximity to other structures can trigger approval on a wall well under a metre.

Confirm your own situation with your council or a private building certifier before you order materials. QBCC licensing is a separate question again for whoever builds the wall.

RPEQ stands for Registered Professional Engineer of Queensland. Engineering registration is a legal requirement in Queensland, not a voluntary badge. Under the Professional Engineers Act 2002 a person who is not a practising professional engineer must not carry out professional engineering services, and a registered engineer must not work in an area of engineering they are not registered for. An unregistered person may only do that work under the direct supervision of an RPEQ who is responsible for it. The Act also applies extraterritorially, so an engineer based interstate still needs registration to provide professional engineering services for Queensland.

Registration is administered by the Board of Professional Engineers of Queensland, and the register is public and searchable by name, location, area of engineering or registration number, so you can verify an engineer yourself rather than trusting a logo. Our concrete sleepers are listed as certified by Registered Professional Engineers of Queensland.

The important distinction: certification of a product is not certification of your wall. Ask exactly what the engineer signed off, what heights, soil types, surcharges and post spacings it covers, and whether your site falls inside those limits. If it does not, you need a site specific design from an RPEQ in the relevant area of engineering.

AS 4678 Earth-retaining structures is the Australian Standard that engineers and designers use to design retaining walls. The National Construction Code accepts it as one way to demonstrate that an earth retaining structure associated with a building or structure is structurally sound, and it was first brought into the NCC as an acceptable construction manual in NCC 2019. According to the ABCB, AS 4678 applies to earth retaining structures between 800 mm and 15 m in height, and it does not cover exceptional site conditions such as landslips, structures subject to sustained cyclic loading, or water retaining structures such as dams and reservoirs. It is a limit state standard, using partial load and resistance factors rather than a single global factor of safety, and the ABCB notes its design life provisions are normative rather than guidance.

It is a design standard, not a product stamp. A material engineered or tested to AS 4678 still has to be used in a wall designed for your own height, soil, slope, drainage and surcharge. The ABCB also notes AS 4678 is one acceptable method among several, so a designer may use other structural design manuals instead.

Standards and NCC clause numbering are revised between editions, so confirm the current edition of the standard and which NCC edition your certifier is working to. Whether it applies to your wall is a call for your engineer or certifier, not for us.

There is no automatic 50/50 split. In Queensland a retaining wall is not a fence. Section 11(2) of the Neighbourhood Disputes (Dividing Fences and Trees) Act 2011 expressly excludes retaining walls, so the cost sharing rules that apply to dividing fences do not apply to a retaining wall. The Queensland Government's position is that retaining walls usually benefit one neighbour more than the other, so they are not normally a joint responsibility.

In practice, who pays turns on who benefits from the wall, who built it, where the boundary actually sits on the survey, any easement or covenant, and any agreement between the owners. QCAT states it can only make orders about work on a retaining wall where repair of the dividing fence depends on that work, so a dispute purely about a retaining wall is generally handled by negotiation, mediation or a court rather than the fencing provisions.

Practical advice from councils: get a survey, build the wall entirely within one lot where you can, and talk to your neighbour before you start work that affects them. This is a legal question rather than a materials question, so get your own legal advice for your circumstances. As a supplier we cannot determine who owns or must maintain a wall.

They describe the concrete and the steel inside a concrete sleeper, and you will see both on our concrete sleeper listings.

MPa is the characteristic compressive strength of the concrete, measured on test samples at 28 days. Under AS 3600 and AS 1379 the standard strength grades are 20, 25, 32, 40, 50, 65, 80 and 100 MPa, so 40 MPa sits well above the grades used for general work and means a denser, stronger and generally more durable concrete.

N12 describes the reinforcement. Reinforcing steel is specified to AS/NZS 4671, where the letter indicates ductility class, so N means normal ductility, and the number is the nominal bar diameter in millimetres. An N12 is therefore a 12 mm deformed ribbed bar of grade 500N, with a characteristic yield strength of 500 MPa. Two of them means two bars running the length of the sleeper.

Why it matters: a sleeper spans between posts and has to resist bending in wet ground for decades, so strength combined with adequate concrete cover to the steel is what keeps it from cracking and corroding. A caution though. A higher MPa number on its own does not make a sleeper suitable for your wall. Bar size, bar spacing, cover, exposure classification and the wall design all matter, durability is driven by exposure classification as well as strength, and you should never substitute a different bar size or ductility class for what a design specifies.

Both are used in the same post and panel configuration, with sleepers stacked horizontally between posts, so the decision is usually about weight and handling, appearance, and what your design calls for.

Concrete sleepers are heavy, which is exactly why crane trucks and sleeper grabs exist, and they give a solid masonry look. Composite sleepers are lighter to handle and are made to resist warping, rotting and termites with minimal upkeep. Timber is the lowest entry cost and is graded by treatment hazard class. Sandstone blocks are a natural feature look rather than a post and panel system.

What we will not do is tell you one material is structurally better than another for your wall in the abstract. Height, soil, surcharge, post size and post spacing decide what is suitable, and above the exempt height that is a decision for your engineer. Tell us your wall dimensions and what you want it to look like and we will go through the options with you.

Treated timber in Australia is graded by hazard class under AS 1604, and the class tells you where the timber can safely go. Business Queensland describes H4 as appropriate for use where the wood is in contact with the ground or is continually damp, which covers fence posts and low landscape walls. WoodSolutions lists H4 as outside in-ground and subject to severe wetting and leaching, and H5 as the step up for extreme wetting and leaching or where the critical use requires higher reliability, listing structural retaining walls under H5.

The Timber Preservers Association of Australia puts H4 at general retaining applications such as low retaining walls less than 1 m in height, and says H5 is required where sleepers contact groundwater, exceed 1 m in height, or serve critical applications. WoodSolutions recommends only Durability Class 1 hardwood or H5 preservative treated timber for engineered retaining walls. So H4 and H5 are not interchangeable. Have your engineer or certifier confirm the hazard class for your wall.

Two other things worth knowing. Branding is mandatory: compliant treated timber carries the treatment plant registration number, the preservative identification number and the H class, and the TPAA is blunt about it, if the timber is not branded it does not comply with the standard. And CCA, copper chrome arsenate, may still be applied to timber for outdoor uses such as fencing and landscaping, but since March 2006 it has been an offence to sell CCA for treating timber intended for garden furniture, exterior seating, children's play equipment, decking or handrails. If your wall doubles as seating, CCA treated timber is not appropriate.

Because water is the single biggest reason retaining walls fail. Soil that cannot drain builds up hydrostatic pressure behind the wall, and that pressure sits on top of the earth pressure the wall was designed for.

The ABCB Housing Provisions identify retaining walls as a typical location where a subsoil drainage system may be needed, and where one is installed the subsoil drain must be graded with a uniform fall of not less than 1:300 and discharge into an external silt pit or sump. The Concrete Masonry Association of Australia's guide to gravity retaining walls states that a properly functioning drainage system is effective in removing hydraulic pressure, which is why drainage is a structural matter and not a finishing detail. That guide specifies nominal 10 mm to 20 mm poorly graded gravel to a minimum thickness of 300 mm against the wall stem, plus a 100 mm slotted PVC agricultural pipe with a geofabric sock or equivalent system, laid at a minimum uniform grade of 1 in 100 and connected to stormwater. A geotextile sits between the retained soil and the drainage aggregate so fines cannot migrate in and clog the drainage zone.

Two practical warnings. The drain has to discharge somewhere lawful, and connecting a subsoil drain to a council stormwater system or discharging across a boundary may need council consent or a plumbing approval. And where an engineer has produced a design for your wall, that design governs over any general figure quoted here. Our drainage management guide walks through the build sequence.

Start with the wall calculator on our home page. Put in your wall length, wall height and sleeper type and it returns a full bill of materials: sleeper quantity and the number of courses, post quantity and post lengths, pier holes, concrete bags, agi pipe size and length, geo fabric, drainage aggregate in cubic metres and wedges, with the matching products linked so you can see what each line costs.

Treat the output as an estimate. Our team confirms the final list before anything is ordered, because a calculator cannot see your soil, your slope, your access or what sits behind the wall. If you would rather not use it, send your wall length and height through Request a Quote and we will do the take-off by hand.

To understand where the numbers come from, our guides cover alignment and steel post positioning, which is where spacing and post counts start, installing steel posts for pier holes and embedment depth, and installing concrete sleepers for how the courses stack up. The installation cross section diagram shows how the components fit together.

Final post spacing, post size and embedment depth depend on the wall design. Where your wall needs an engineered design, use the spacings in that design rather than the calculator estimate or a rule of thumb.

HYBUILT offers a design and construct solution. We do not publish an installer list, because the right crew depends on the job and where it is. Contact us with the wall dimensions, the site and the suburb the job is in, and we will either take the build on ourselves or recommend an installer who works in your area. See Delivery and Installation for how that works.

If you would rather build it yourself, our installation guides run in build order: site preparation, alignment and steel post positioning, installing steel posts, installing concrete sleepers, drainage management, attaching a fence on top, and an installation cross section diagram. Keep in mind that council approval and QBCC licensing requirements may apply depending on the wall and the value of the work, so check before you start.

We do not publish a maximum retained height. Every retaining wall has its own conditions, and the height you can build to depends on the soil, the surcharge behind the wall, the post size and spacing, the footings and the approval path for your site. Contact us with your wall dimensions and what is going on behind it and we will give you clarity on the specifications for your wall.

It is commonly done, either with fence post brackets or by running the wall posts up higher. We supply the brackets and there is a guide dedicated to it: attaching a fence on top of the retaining wall.

Two cautions. Structurally, a fence on top adds load, including wind load, to the wall and the posts, so it needs to be allowed for in the design rather than bolted on as an afterthought. For approvals, some councils treat it as a trigger in its own right: the Gold Coast looks at whether the combined wall and fence height stays under 2.0 m, and Sunshine Coast Council requires building approval to increase the height of an existing wall or add a fence on top of it. Check with your council or certifier before you commit.

Yes. HYBUILT Trade Membership is built for tradies, landscapers and contractors working in civil, commercial and residential construction. Members get product discounts, priority service and early access to special offers. Apply through our Trade Membership page, where you will need your business and billing details. Once your account is set up, mention your account email when you request a quote so member pricing is applied.

Send your project details through the Request a Quote page and our team puts together a tailored quote including delivery to your site, usually within one business day. The wall calculator on our home page will build an estimated materials list from your wall length, height and sleeper type if you want a starting point before you send the form.

Include your products and quantities, or just the wall dimensions if you want us to do the take-off, plus your delivery suburb or town, whether you need installation, and your timeframe. Trade members should mention their account email. You will receive a formal quote by email with a secure payment link, and once it is paid we schedule your delivery.