I get asked this from time to time by customers, particularly those who have never had their carpets cleaned, or customers who have heard scare stories from family & friends, who have experienced carpet shrinkage post clean. There is a risk from shrinkage but this usually down to operator error, or carpet cleaners who haven’t undertaken any formal training.
What Is Shrinkage
Shrinkage is found in carpets which contain natural fibres i.e., Jute. The main culprits are woven backed carpets, though hessian backed carpets can if seriously over wet, shrink.
What causes Shrinkage
Excessive moisture from cleaning, (pre sprays, DIY extracting) can run into the jute fibres which swell when they come into contact with moisture. Manmade fibres which do not absorb water are the most at risk as moisture can penetrate the backing with just pre spray and shrinkage can occur.
Woven carpets like Axminister’s & Wilton’s are at most risk of shrinkage, however as these have a woollen face fibre, they retain most of the moisture. However, there are woven carpets that have polypropylene face fibres, and these have no water retention, so any over wetting will bypass this and go straight into the foundation (backing) causing shrinkage. These polypropylene woven carpets are known as Belgium Wilton’s. When I come across a woven carpet, its important I ascertain what the face fibre is before any carpet cleaning is undertaken.
Once face fibre and construction has been confirmed I can then safely decide how to clean a problem carpet and continue safely without any shrinkage occurring.
