Usually, slipperiness is caused by algae or dirt on top of the deck or terrace. A full cleaning treatment should restore the natural grip of the wood or stone. If slipperiness is a persistent problem, consider installing grip mats in high traffic areas of the deck.
Hebden Bridge
Hebden Bridge is a market town in the Upper Calder Valley in West Yorkshire, England. It is 8 miles (13 km) west of Halifax and 14 miles (21 km) north-east of Rochdale, at the confluence of the River Calder and also the Hebden Water. The town is the biggest settlement in the civil parish of Hebden Royd. In 2015, the Calder ward, covering Hebden Bridge, Old Town, and part of Todmorden, had a population of 12,167 the community itself has a population of about 4,500. It is recognized for being an LGBT-friendly community, as well as has actually been called the UK's "lesbian capital".