What Should Australian Contractors Expect in a PEB Erection Drawing Package?

Key takeaways

• A PEB erection drawing package is the on-site erection working guide and should be checked for completeness and revision before erection.
• These connection details, anchor bolt plans, and bolt schedules are the closest to be reviewed because they lead to the most delays and safety concerns when found to be incorrect.
• Eliminating disputes, rework, and enabling the site team to work from a single set of information by having a clear specialist detailing the support process.
• Drawing providers are to be chosen based on experience, not price, not only because of the individual's expertise with the subject, but also because of the checking process and the approach to revisions.

What is a PEB erection drawing package?

A pre-engineered building is the shortened name for a building constructed from factory-cut steel components that are assembled on site. The drawings are much more important than they would be on a typical steel building where some components have to be fitted by hand. The erection drawing package serves as a link between the engineering design and the works on the ground.

There is a lot of confusion between erection drawings and fabrication drawings. Fabrication drawings are used to explain the procedures used to cut, drill, weld, and finish each piece in the workshop. Erection drawings illustrate the way in which those completed items fit together on site. They indicate where each member goes, how it is lifted, and designate bolts and the sequence of standing the frame up. A contractor with only fabrication drawings may have an idea of what the parts are, but not be aware of how to construct the building safely.

However, commercial and safety aspects of the project are also added to erection drawings. They assist the site manager with planning crane hire, staffing, and inform the client about the progress. They provide a reference for temporary bracing and fall protection for the safety officer. Once the package is ready, all team members use the same information. If it is not done, each person on the site makes assumptions, and assumptions are the source of errors.

That is why it's so important that seasoned contractors look at the package before any trucks are loaded. They verify the sheets are in accordance with the approved design, that revision numbers are up-to-date and quantity on the drawings are consistent with the delivered material. This review can be done up front, but saves on costly delays later.

Core documents included in the package

A typical package is designed as a set of sheets, with each sheet covering a different portion of the structure. Most packages consist of the following essential documents, although the number will depend on the size of the building.

General Arrangement Drawings

General Arrangement Drawings are drawings that depict the overall layout of the building. They involve plan views, elevations, and sections that present lines of columns, spacing of bays, roof slope, wall heights, and window and door openings. Before the crew looks at any detail, these drawings provide them with an overall view of the entire structure. They play a key role in ensuring that the building conforms to the site plan and the approved design.

Foundation Layout Plans

A foundation layout plan will indicate the location, size, and elevation of each footing or pad. They also show the necessary concrete strength and reinforcement information. The positions of foundations must be correct before erection commences, and even a slight mistake in position may prevent the steel frame from being fitted. Good packages contain dimensions from a fixed reference point, and it is clear what tolerances are called for.

Anchor Bolt Plans

One of the most vital sheets that make up the package is the anchor bolt plan. They indicate the exact location, diameter, projection, and embedment of every anchor bolt, and the layout of the bolt group and the template to be used. One of the biggest time recorders on PEB projects is improper anchor bolt placement, and these plans should be confirmed with the concrete contractor prior to pouring.

Member and Connection Details

Each member is connected to another member through the connection details. These include end plates, cleats, gussets, bolt patterns, weld symbols, and stiffeners. A lot of times they're drawn at a larger scale so the crew can see exactly how the pieces are going to fit together. The connection should be the same as the part marks on the member drawings and the amount of the bolt schedule.

Bolt Schedule

The bolt schedule contains a list of all of the bolts in the structure. It contains bolt size, grade, length, type, and number of washers required for each location. Bolt schedules are used to order the correct fasteners and ensure that no fasteners are being missed prior to erection. They also indicate if a bolt must be pre-tensioned to be tightened, which will impact what method is used to tighten and the inspection records.

Erection Sequence Notes

Erection Sequence Notes are notes that explain the sequence in which the structure is to be erected. They describe the order of erection of the first frames, installation of bracing, installation of purlins and girts, and the commencement of roof sheeting. Sequence notes are used to secure stability of the building during construction, as a partially completed frame may be open to wind and to accidental overloading.

How are erection drawings organised?

Most PEB erection packages are numbered in a logical way for the site team to be able to easily locate the correct sheet. Sheets are usually organized in sets to include general drawings at the front and detailed connection sheets at the end. The table below summarises the typical grouping and what each group is used for on site.

Another component of a well-organized package is a sheet index and a revision history. The index includes a list of all the drawings, their number, title, and current revision. The change history shows the changes, and when and why. The site team should make sure that all sheets on site are in the same revision as the index before starting work. A common mistake made is to have two different versions of a drawing: one in the site office and one elsewhere.

A good contractor will also seek out a distinct title block on each sheet. The title block must include the project name, client, building number, scale, date, building status, and name of the approving engineer. In cases where one of these elements is missing, the sheet should be discussed before use.

What details should contractors check first?

Not all specifics of a package require the same type of focus. Some have a direct impact on safety and structural performance; others primarily have an impact on speed. The following checks are best conducted before the site visit and are a good use of time.

Connection Details

The first and foremost element to review is the connection details. Verify that the bolt sizes, plate thicknesses, and weld sizes that have been mentioned in the connection drawing are correct from the member drawing and bolt schedule. Make sure the bolt holes are aligned with the bolt holes on the mating member, and there is adequate edge distance and spacing for the bolts to be driven with a spanner or wrench. A complicated connection is a difficult connection – it will be difficult on site if it is difficult on paper.

Member Marks

Every member of a PEB possesses a part mark that is the code that connects the physical piece to its drawing. Before erection, the team must verify that each member possesses a legible mark, the mark corresponds to the delivery list, and that the same mark is used on all sheets. Where marks are not consistent, it may be possible for a rafter to be placed in the wrong bay, and only be realized when the part of the cladding is in place.

Bolt Schedule and Quantities

Bolt schedule should be counted on the delivered bolts prior to the beginning of work. In many cases, it's simply the bolts that are missing, and this is especially true when installing in a remote location; a bolt can take days to reach the site. Check to confirm the lengths, grades, and coatings, as well as quantities, as a bolt that fits the hole but is not the correct grade can pose problems at inspection.

Dimensions and Tolerances

Verify key dimensions on the General Arrangement are consistent with Foundation Layout and Site Survey. Be mindful of the clear height, bay spacing, and the total length. Typically, erection tolerances are specified on the drawings or in the specification, and the site team should be aware of them before the first column is lifted. If the frame is only slightly out of tolerance, it can cause stress in the connections and be a challenge to secure cladding later.

Lifting and Handling Points

For heavy members and assemblies, the erection notes should mark out points for lifting. The crew should ensure that the lifting points are well-marked, that the weight is known, and that the crane has enough capacity for the radius and height of lift. Any lifting points marked anywhere other than on the drawings should not be established on the site without engineering approval.

Which standards apply to PEB drawings in Australia?

PEB drawings in Australia are created based on standards recognised in design and construction. AS 4100, the main steel design standard, applies to the design of steel structures. Loading requirements are normally derived from any of the AS 1170 series standards which prescribe the wind action, live and other actions the building should be able to withstand. The National Construction Code will also establish performance criteria which the finished building will need to comply with, such as structural capability, fire resistance and accessibility as appropriate.

It doesn't matter if contractors are not design engineers; understanding these standards is beneficial. Simple awareness is a means for the team to be more confident in reading the drawings and asking more questions when they aren't sure what is happening. For example, if a wind classification or a design life is indicated in the drawings, the site team should be aware that this information is based on the design and cannot be altered on site without authorization.

Additionally, the package needs to also include the specification for the project, including reference to material grades, coating systems, welding criteria, and hold points for inspection. The drawings and specifications often conflict, resulting in many disputes on site. In this instance, the contractor should make a formal enquiry instead of deciding on the interpretation that will fit the schedule. It is the responsibility of the engineer of record to decide on the solution and provide a written answer; this should be attached to the drawing package.

Standards are important in coating, as well. Galvanising, priming, and topcoat systems are typically specified in the project documents and should match the environment. Corrosion protection systems will be more critical in a building located near the coast or in an industrial area versus a dry inland area. The cost of these repairs is likely to run from a few years after handover for contractors who fail to take the step.

How do detailing services support site work?

Not all contractors have an in-house team to create or review erection drawings. In such cases, expert assistance is beneficial. Good PEB detailing services in Australia are there to fill the gap between what is intended in the design and the site's requirements. They take engineering data and make it into drawings that are easy to build, and verify that every connection and member can be joined as depicted.

Typical activities for detailing support include creating fabrication and erection drawings, creating bolt and material schedules, and checking for clashes and missing information. Many projects require the detailer to also make erection sequence notes and to help coordinate revisions to the design when design changes are received late. The work minimizes on-site questions and speeds up the time to completion from delivery.

Quality detailing also helps in communicating between the two parties. If it is a well-checked package that the contractor, fabricator, engineer, and client all work from, the number of disputes will go down. The detailer can be the one who receives all technical questions from users, thus saving the site manager time. The package is made simpler to use for everyone by clear sheet numbering, consistent naming, and accurate cross-references.

Contractors should inquire with their possible detailing partners regarding their checking procedure. A solid provider will be able to outline how they verify members with connections, how they track revisions, and how they handle revisions post-approval. They are also expected to provide examples of the past packages they have worked on that are comparable to the building in question to determine the amount of detail the contractor should expect before committing.

What are the common mistakes on site?

In spite of an excellent package, some of the errors recur on a PEB project. It's much easier for the team to prevent these problems than to resolve them after they have occurred.

• Using superseded revisions that were left in the site office after an update was issued
• Placing anchor bolts at incorrect depths or projections, usually due to the lack of a template on top of the newest foundation drawing.
• Blending right- and left-hand members that are nearly identical but connect at different points.
• Bolting parts in the incorrect sequence to cause the frame to be warped and difficult to connect later on
• Lifting of temporary bracing before the frame is sufficiently stable to carry the building's wind and construction loads
• Using components that are similar, but not approved, for making substitutions without consulting the engineer.
• Overlooking small dimensional variation along a series of bays which eventually lead to misalignment of the cladding.

Many of these errors are just a matter of simple habits – check before cutting, lifting, or tightening. It's much more cost-effective to take 5 minutes to review the relevant sheet before the activity than to spend a day fixing an error. Supervisors should also ensure that all crew members are aware of the location of the current drawings and how to ask for clarification.

A frequent issue is lack of communication between the Office and site. Drawings can be changed in the office as work progresses and is completed using the printed copies. This can be solved with a simple system of dated, controlled copies, old copies clearly marked with a date or removed. A few contractors will also maintain a brief record of questions and answers, allowing for a record of decisions and to safeguard all parties.

How can contractors verify a package before erection?

To ensure that the package is complete, correct, and usable before erection is called verification. A structured approach is time-saving and will build the team's confidence. The sequence outlined below is a practical application that most contractors can follow.

1. Verify that all the sheets have been revised, and that the latest issue register has been followed by the designer.
2. Ensure the general arrangement is consistent with the site survey, building outline, and planning conditions.
3. Check the setting-out points against the surveyor and compare the layout of the foundation and anchor bolt plan with the concrete drawings.
4. Count the delivered members against the material list and ensure that each part mark is on a drawing.
5. Verify the number of bolts, nuts, and washers against the bolt schedule; verify grades and coatings on delivery notes.
6. Go over the erection sequence with the crew and the supervisor, making note of any step that will require temporary support or special lifting.
7. Write down any questions and get them answered from the designer or detailer prior to any work being done on the affected vehicle.
8. Ensure the approved package is stored in a controlled area and superseded copies taken from the working area.

For a typical building, these steps can be carried out by a small team in one or two days. More complex or larger projects may require a longer review period, particularly when the structure features unusual roof geometry, or crane beams and mezzanines. Time to be spent on verification should be included in the project programme and not squeezed out when the schedule is tight.

It's also beneficial to have a brief pre-erection meeting as well. Bring the site manager, foreman, crane operator, surveyor, and one of the detailers or fabricators. Do the first couple of lifts as a group and make sure everyone knows the sequence. A host of problems which would otherwise have come up on the first day of erection are raised and solved at this meeting.

How should contractors choose a drawing provider?

The right provider for drawings will influence the quality of the package and the smoothness of the entire project. Contractors that work with PEB erection contractors Australia frequently experience the best outcome when the two groups are familiar with both design and practical aspects of PEB erection. A provider who has previously worked on buildings in the region will have an idea of what to expect with regard to wind and coating requirements and will be alert to these issues early.

Contractors should consider a number of aspects when comparing providers:

• Experience: The first is experience of the type and size of the building. The team that has successfully created packages for warehouses might not be a suitable choice for a multi-storey steel structure where connections are complex.
• Checking Process: The second is the quality of the checking process. Inquire about the process used to double-check work, the person who reviews the work, and the amount of time required for the review.
• Communication: The third is communication. A quality provider is fast to attend to inquiries, clearly explains their drawings, and is willing to visit the site.

Price is important; however, it should not be the deciding factor. A low-cost package that is incorrect will be significantly more expensive due to delays, rework, and disagreements that will occur as a result of the initial error. Contractors should request a definitive scope of work that specifies the sheets to be produced, revisions to be included, and post-issue support. This allows for easier comparison of quotes on a like-for-like basis.

Finally, contractors should take into account the provider's attitude to change. Construction projects are subject to design changes, and a provider that can keep up with the changes and issue an updated package in a timely and precise manner is more valuable than one that takes weeks to reissue sheets. Inquire about how long it takes for revisions to be made and how the changes are communicated to the site. A clear change process safeguards the programme and minimises the risk of operating on the basis of out-of-date information.

Final verdict

The PEB erection drawing package is essential for contractors in Australia to make any steel building project successful. It contains all the details such as layout, connections, and sequence, among other information that is required by the site crew to make the project safe and accurate. The knowledge of what a package needs, as well as which sheets are important and how to verify them before starting the work, helps the crew in their planning.

Proper detailing assistance, efficient communication, and a responsible attitude towards changes in the drawings complete the whole picture. The contractors, who understand their drawings, will be able to make the art of erection easy and to finish the project within the set budget and on time.

Frequently asked questions