3CR12 is proving to be a cheaper and easier option over the long term when considering other materials
Charles van der Heever is an accountant at a furniture company and has been living in a suburb of one of our larger cities for a number of years*. He lives in his own house with his family and recently became a crime statistic when his house was robbed while the family was away for the weekend.
The insurance company paid out on the condition that he must upgrade his wooden fence to a security palisade. This meant Charles would have to remove the current wooden picket fence and replace it with sections of palisading. The posts for the wooden fence are brick columns and Charles decided to keep them since they were conveniently spaced at exactly 3m intervals. He needed six panels to replace the old fence.
Like all families, Charles’s household is feeling the current financial pressure and the costs for erecting a newly bought security fence from a specialist company did not meet his budget. Charles knew that the money for this would have to come from a bank loan. However, Charles’s neighbour is quite the handy man and told Charles that he could most likely fabricate the panels of palisades for him at a much better price than the
Charles and Fanie Gouws, the neighbour, did some industrial espionage and in no time copied a design a few blocks down from a church hall. It was decided that the fence needed to be 1.8m high with upright members made from 40x40mm angle iron and spaced at 160mm would be adequate. The uprights will be mounted on 2 lipped channels forming horizontal members. The design weight for a 3m section was calculated to be 78kg. Charles now realised that the surface of the fence would need to be painted with care and with a good product because he didn’t want the paint colour to fade over time and he is aware that corrosion is an issue in the area. Charles, Fanie and most of the residents make use of ground water when irrigating their gardens and the water quality is not good. It has high levels of iron – staining walls and fences – and is fairly brackish. Charles started to look into better surface protection since he was in no mood to paint every year. During his investigation into powder coating he was told about 3CR12, a cost-effective stainless steel that was supposed to outlast mild steel at a reasonable additional cost.
After consulting Fanie, Charles did his homework on the stainless steel. No sections are available in 3CR12, but Charles discovered that services are available where 3CR12 sheet is laser cut and then formed into angles and lipped channels for a reasonable fee. This allows for mounting holes and the like to be profiled during the process, saving on assembly and installation costs.
Fanie can work with stainless steel, but warned Charles that the consumables like welding rods would be more expensive. Fanie also mentioned that the welding areas need special cleaning to protect the corrosion properties of the material.
Charles got his quotes together and started to compile a table to summarise and compare his options. He noted that he could powder coat mild steel or investigate the options of powder coated or uncoated 3CR12. While discussing the “aged” look of 3CR12 with a representative from Sassda, he learned that an application is available to do a life cycle costing for different options.
This made the process much easier than anticipated and Charles prepared the information to be processed in the application.
He spoke to his bank regarding a loan and was told that he can expect to repay the loan at an annual interest rate of 11%. He also assumed that the inflation rate will not deviate significantly from 6% for the foreseen future. As this is an attachment to his house, Charles decided to evaluate the project over the number of years that he expects to stay there. He estimated this to be another 15 years.
HE CALCULATED THE COSTS PER PANEL TO BE THE FOLLOWING:
Mild steel offers the convenience of ready formed profiles. The design made use of standard angles and sections. The panel will be powder coated and maintenance on it will entail cleaning off the peeling paint, treating rusted areas and repainting all affected areas. Charles realised that the maintenance will be fairly expensive and that it needs to be done every 3 years after having a look at the general state of similar fencing in the
Mass = 78kg
Material costs = R1620
Powder coating = R2340
Fabrication costs = R540
Installation costs = R120
Maintenance painting costs = R1404
Maintenance period = 3 years
3CR12 SECTION COSTS:
Due to the fact that some customised design could take place during profiling the sections from sheet, a slightly lower weight could be achieved. The fabrication cost is higher since Fanie had to use stainless welding rods and chemicals to treat the welds. The panel will also be powder coated, but since paint does not peel from stainless steel surfaces, the maintenance will be much less than on mild steel.
Mass = 75 kg
Material costs = R2100
Powder coating = R2250
Fabrication cost = R750
Installation costs = R120
Maintenance touch up painting = R375
Maintenance period = 3 years
Charles has the option of not powder coating the 3CR12. The Sassda expert told him that the material will age with a brownish patina that will get an even tone over time. This finish will not rust or give off metal particles, but will not be shiny. A good option in an environment that is anyway stained by irrigation water, Charles thought. He also realised that this fact will bring down his initial costs drastically with no powder coating required, but this will also mean no maintenance costs over the lifespan.
The Sassda expert also told him that at the end of the lifespan the stainless steel components would still have a high residual or scrap value. Fanie told him that rusty mild steel has got very little value. Charles decided to assume that the scrap value of mild steel will be zero and set a scrap value of R500 per panel for the 3CR12 option.
Charles and Fanie was amazed to learn that over the 15 year period mild steel will cost more than double that of the uncoated 3CR12.
After a few celebratory beers, Fanie proposed that they go for the powder coated 3CR12 option since it is around 30% less than the mild steel price over the life span, although the latter has a 13% higher initial cost.
Charles wanted to follow the low cost route and eventually consulted his wife, Helena, regarding the aesthetics of the planned fence and her decision was to settle for a “historic houses” green powder coated finish.
The material was ordered, Fanie did a fantastic job and the Van der Heever family was delighted with the end result.
And so was the bank manager and the insurance company.
Note: This case study is a fictional story based on actual figures. The case study is not intended to promote any material or surface coating, but rather to illustrate the value of doing a proper life Cycle evaluation before making any final decisions based on initial costs only. The full breakdown of data used and assumptions made are available from Sassda.