What is structural damage?
Tub and showers are built to withstand a good amount of weight, which for tubs includes the weight of water. Normally this is done with particleboard underneath the unit, fiberglassed in as the unit is manufactured. Over time, these boards can separate from the floor of the tub, causing the floor to move and flex during use. The deteriorationcould be gradual, or be sudden. Once there is movement in the floor, ultimately it will lead to cracking in the floor, which could potentially let water under the unit.
How we repair structural damage
To repair a weak floor, with or without cracks, we must support the floor from below. We accomplish this using a structural foam designed to expand under the unit, bridging the gap between the floor and the bottom of the unit. We drill small holes in the floor for injecting the foam under the floor, which when we are done, are repaired like any other damage to where you can't see them. This can either be local to a damaged area, or across the whole floor depending on how severe the movement is.
The foam we use is a structural foam designed specifically for weight-bearing. We do not use foam intended for insulation or gaps around doors and windows, as these remain flexible and are not strong or durable enough for repairing floors.
After the repair process, you will have confidence in the ability to use the unit again without damaging the floor. It will feel solid, not make any sounds, and appear just like the original floor did before.