Yes, it is possible to add new wood or composite decking over an old cement patio without tearing everything out first. This can be done using a variety of methods, including using sleepers or a substructure system.
Here's a general outline of the process:
Assess the condition of the existing cement patio: Make sure the patio is in good structural condition and free from any significant cracks or damage. It should also be sloped away from your house to ensure proper drainage.
Clean the patio: Thoroughly clean the cement surface, removing any dirt, debris, or loose material. You may use a pressure washer or a suitable cleaning solution to achieve this.
Install a drainage system (optional): If your cement patio doesn't have proper drainage, you may want to consider adding a drainage system to prevent water buildup. This can be achieved by creating gaps between the sleepers or using a specific substructure system that allows for water flow.
Create a substructure: The substructure provides the framework for your new decking. There are a few options to consider:
Sleepers: Sleepers are pressure-treated or composite boards that are placed directly on top of the patio. They act as the support structure for the decking boards. Ensure the sleepers are level and properly spaced to accommodate the size of your decking material.
Substructure systems: Alternatively, you can use specialized substructure systems designed specifically for installing decking over concrete. These systems often consist of adjustable pedestals or metal brackets that are secured to the concrete, providing a stable base for the decking.
Install the decking: Once the substructure is in place, you can begin installing the wood or composite decking boards according to the manufacturer's instructions. Ensure that the boards are properly spaced and fastened securely to the substructure.
Finishing touches: Finally, complete any necessary finishing touches, such as adding trim boards, fascia, or railing systems, as desired.
Remember to check with local building codes and regulations before proceeding with any construction project to ensure compliance and obtain any necessary permits.
It's worth noting that while adding decking over an existing concrete patio can be a viable option, it will increase the height of the surface. Consider how this might impact door thresholds and any surrounding structures before proceeding with the installation.