Outdoor tiles or pavers have been a mainstay of hardscaping for a very long time, especially in rooftop applications. Whether you install them with a pedestal system or use the more traditional adhesive method is up to you, but each offers a variety of benefits. Here are the advantages and disadvantages of each approach.
The Traditional Method: Porcelain stoneware (tiles or pavers) glued to the substrate. This system involves using adhesive to stick the tiles to the floor permanently. Glue is applied to the pavers, and then they are stuck to the waterproofing located on the screed beneath.
Once the tiles are stuck to the substrate, the gaps between the tiles are tightly filled with joint mortar (sometimes polymeric sand) to protect the exposed places from water penetrating under the tiles. The space beneath the glued tile must be fully filled, as any free space may cause future issues. Rain, humidity or temperature changes can cause water to accumulate in any remaining gaps. This water can, in turn, freeze, expand and cause irreparable damage.
Because anti-slip outdoor tiles are rigid, they do not play nicely with the settling and shifting of the surrounding landscape. This can create tension within the stone, leading to cracks in the stone and the surrounding joints.
With this system, no damage is a simple fix. Even a single broken tile or issue beneath one will lead to significant repairs. Generally, it means all materials must be replaced and the project rebuilt. If the damage is addressed quickly, it may be possible to replace only the stone, glue, grout and lining. If the damage is left too long, water may penetrate into the ceiling of the room below, causing significant structural damage.
Creating an outdoor raised floor can be complex if your substrate is uneven. You may find yourself dealing with plenty of waste, along with frustration.
The Pedestal System Method: Tiles are affixed upon adjustable plastic pedestals at regular intervals, with no glue, grout or joint compound required. The weight of the tile creates enough pressure to keep the floor level and strong.
The inherent nature of tiles mounted upon pedestals means that water is encouraged to drain below the tiles. Because pedestals create a raised floor, the water drains off between tiles and off the roof via the drain in the substrate below. No water remains to freeze & expand. Should a tile ever need to be replaced, each can be replaced separately without issue.
This raised floor created by the pedestals also offers a convenient way to disguise plumbing, electrical and HVAC services beneath, making excellent use of the space.
Because no adhesives are used, pedestals have no impact on expensive roofing membranes. There is also no waiting for things to set. Once your pedestal project is complete, it is ready for immediate use.
Adjustable pedestals can easily overcome the challenge when dealing with an uneven surface below your project. Most offer the ability to adjust for slopes of up to 5%, making flat, level floors a breeze.
The choice is clear. Modern pedestal systems simply make the job easier and faster while delivering better results.