According to the statistics, carpets made with synthetic fibre have a market share of 99% in North America, which means negligible amount of wool carpets are sold. Of course, carpet cleaners still encounter wool carpets from time to time because they might be laid there decades ago. Wool carpet is facing a declined market share, and such trend should also exist in Australia. However, being a lucky country “riding on the sheep’s back”, my personal experience is wool carpet is still widely used in new buildings, particularly in newly developed city apartment buildings. Once I told a customer, a tenant moving out of his city apartment, the carpet fibre is likely to be wool based on my test. He dismissed my claim and said it should be made of cheap plastic. I had no intention to argue with him and said it might be a blend. The customer quickly delivered the news to the owner and minutes later, the owner texted back and asked the tenant to confirm from me that it is not pure wool, because he did not want to be cheated by the selling agent and the developer. The morale of this story is both the developers and the home owners probably regard wool carpet is the attachment of upper class taste.
From a carpet cleaner’s point of view, there are good reasons for wool carpet losing its market share. Except for relative expensive, wool carpet is notorious difficult to maintain and clean. Like all natural fibres, you cannot use high pH detergent on wool carpet, because the high pH (increased alkalinity), can destroy the cell membrane of wool, thus cause potential carpet browning. However, high pH maybe crucial in removing oily soil attached to the carpet. Generally, the higher the detergent’s pH, the better its cleaning effect would be. Carpet manufacturers often recommend wool carpet to be steam cleaned with pH detergent of 8.5 or less, but in reality, pH of 10 and above are often required to clean the oily carpet. To overcome the problem, most of carpet cleaning chemical manufacturers make dedicated wool carpet detergents (presprays) with increased concentrations of non-ionic surfactants and organic solvents to enhance the detergency, with the cost being increased significantly.