Yes, carpeted stairs are generally considered safer than stairs with hard surfaces like wood, vinyl, or tile. Carpet provides more traction, which helps reduce the chances of slips and falls, and its cushioning can lessen the severity of an injury if a fall does occur. Hard surfaces often lack the friction needed for a secure tread and can be quite slippery.

However, it's worth noting that some carpets can also be slick, particularly if they are brand new, dirty, or made from certain materials. If any stair surface feels too slippery, traction treads can be added to most materials to increase grip and improve safety.

In most cases, you do not need to put padding or underlayment under carpet tiles. Unlike traditional carpet, which requires a separate pad, carpet tiles are designed to be installed directly onto a firm subfloor like plywood, concrete, or tile. Many carpet tiles come with a built-in underlay and attach with peel-and-stick adhesive, double-sided carpet tape, or glue. For a more comfortable, cushioned feel, especially in residential settings, you can opt for padded carpet tiles that have a thicker underlay attached. While it's generally not recommended to install a separate pad, a compact underlayment might be used in some situations, though this typically requires professional installation. An acoustic underlay may also be considered in commercial spaces or multi-level homes where noise reduction is a priority.

If the installer is unwilling to fix the problems and you’re not interested in seeking remediation, you could hide a visually unpleasant floor. This will only work if the floor is structurally sound and the only issue you have is the way it looks. The easiest way to do this is to use large area rugs. You can also paint the floor, although that’s a labor-intensive job if you want to go the DIY route.

When deciding whether to repair or replace your carpet, consider its age, the extent of the damage, and its location. It's often best to replace the entire carpet if the damage is extensive, such as large sections needing replacement, or if it's caused by water, which can lead to mold problems. Similarly, if your carpet is nearing a decade old, replacement is likely the more logical choice. On the other hand, consider repairing your carpet if the damage is localized to one spot, like minor rips or snags, the carpet is still relatively new, or the damage is in a low-traffic area of your home.