Ground level decks are generally suitable DIY projects
Raised decks involve structural engineering skills to ensure that they are safe
The construction of low-level decks is a project usually within the scope of most DIY enthusiasts. However, when building the deck, it is important to follow the recommendations of the product manufacturer and TDCA guidance if you want to ensure your decking will provide a long and trouble free service life. A professional installer will of course be more than happy to undertake any project, small or large, if you prefer to enlist some help.
If your plans are for a raised deck or include changes of level, specialist expertise is required to ensure the deck is structurally safe for the people using it. It is for this reason that the TDCA recommends experienced installers who will ensure that the deck is properly engineered and fit for purpose.