Structural steel fabrication prices in Melbourne can vary widely, even just from one day to the next. Considering that major construction projects take months to years to complete, failure to account for potential fluctuations across the proposed time span of the project can throw your budget and the entire project into a tailspin.
Having a good and accurate estimate is crucial to competitively bidding and winning major projects, but unexpected purchase prices for the steel can whittle away at your bottom line at the end of the road, compromising the value of any win to your own bottom line. Here are a few tips and some examples on how to arrive at the best estimate for structural steel.
Some Things to Keep in Mind
Material purchase location and quantity being purchased are central considerations when estimating structural steel. Warehouse prices generally apply to small orders, while mill prices apply to large orders, and pricing for each respective type of outlet varies.
Keep in mind that prices offered by a supplier or manufacturer are quoted as of the time of delivery, which means future deliveries are subject to the same laws of fluidity in pricing. Incorporating an escalation clause into a contract to deal with unexpected rising material costs may help absorb any increases. The framing system of a building typically contributes a minimum of 10 percent to 12 percent, sometimes more, of the total building cost.
Overview of Labor, Material, Equipment, Indirect Costs and Approach to Mark-ups
The example in this technical paper will be a straight-forward demonstration of how to takeoff andc develop pricing for a two-story steel framed medical office building. The structure will include beams, columns, composite metal decking and miscellaneous connections. Because the example is presented in
the design development stage, the framing plans and details do not provide all beams and connections. Therefore, the estimator will need to work up additional allowances based on historical data and an analysis of the takeoff and pricing to ensure that all potential costs are covered.
Material Structural steel members are taken off by linear footage, either manually on hard copies or by using electronic plan reading/takeoff software such as On-Screen Takeoff. Structural BIM models may also be used, such as from Autodesk’s Revit, and can be taken off automatically by specialized software such as Innovaya. One must be careful that the data in the BIM model is accurate, and even with automatic takeoff software it is good practice to perform some spot checks and ratio analysis of quantities from plans. Total length for each beam or column type is then multiplied by that member’s weight per linear foot in pounds to arrive at a total weight, which can then be converted into tons. Metal decking and concrete topping will be quantified by calculating the floor and roof areas. Lastly, allowances for undeveloped beams/design will be accounted for that can reasonably be assumed to be included, as well as an overall percentage of additional tonnage for miscellaneous connections, plates, bracings, etc.
The labor costs are the costs of the erection crew on-site, as structural steel is fabricated and rolled in
the shop. Per RS Means and as generally accepted, it is assumed that for erection a crane can pick
between 35 and 60 pieces a day, with the average being 45 picks per day. With a general assumption of
typical sized beams, girders, columns and connections this would amount to approximately 20 tons
installed per day.
Structural steel erection crews use specific equipment to construct multi-story buildings, typically either
mobile or tower cranes. Special cranes can be used in unusual conditions or where clearances and
access to the jobsite are limited. The equipment can either be owned by the erection company or
Indirect Costs / Mark-ups
There are secondary, indirect costs associated with the erection of structural steel. There are safety
factors to consider, such as perimeter fall protection among others. Also, supporting foundations and
power must be provided when tower cranes are to be used. Another cost that must be factored into the
subcontractor’s price is their overhead and profit, sales tax, performance and payment bonds, and also
Cost Estimation software for steel estimation of constructions
The ConstruSteel solution Cost Estimation is used for cost estimations of steel structures, aluminum structures, roof and wall cladding, etc. This steel fabrication estimating software is much more advanced compared to a steel beam calculator or construction calculator. All the details of construction and cladding such as: materials, hours, stock, etc. can be entered quickly and very detailed creating an instant quotation of the structure. With ConstruSteel’ s Cost Estimation it is possible to import 3D projects from CAD / BIM systems such as Tekla Structures. Steel fabrication estimating in Excel or other steel estimating spreadsheets are no longer needed, but still steel estimations can be imported into ConstruSteel.
Use Cost Estimation as stand-alone or as part of ERP Package
The specific Cost Estimation solution can be used in structural steel companies for one or more steel fabrication estimators as a stand-alone application, but is also included in the ERP Packages. Materials can be imported automatically (manual input is also possible), including advanced shortcuts for structural steel materials and operations. With the steel fabrication estimating software by ConstruSteel every part of a solid cost estimation for a steel construction is included and will save a lot of time for a steel estimator. Cost estimators will discover the ease of how to make a good steel estimation in ConstruSteel.