We do decking supply install, and varnishing with solid wood. Usually we will recommend to use Chengal Wood only. It is because this wood is more lasting for outdoor and is hardwood that can use outdoor.
Decking installation usually for garden and pool side. The base of the decking should be concrete flooring that we can nail the 1″ x 2″ batten as structure or some need to use 2″x 3″ depend on the condition.
Chengal decking has 2 type of installation, which is nail system or clip system. If you use mostly long wood, I will suggest you use nail system, because it will be more flexible for installation and outcome will looks nicer.
Decking grinding and varnishing work usually should carry out every 3 years, it is also to check if any rotten wood to be replace. But to revarnish decking, it should be done every year. It is because the coating on the decking will wear off from time to time under weather and traffic.