A modular step system for in-ground swimming comprising a bottom central hub, a brace assembly, a top central hub, a tread support assembly, a step form and a liner. The components of the modular step system interlock and snap together without fasteners. Also, the components of the modular step system are obtained by molding plastic material or curing of a curable material. The modular step system is installed on a level concrete floor of a swimming pool and designed to be rigidly fixed from behind to adjacent pool walls. The modular step system is adaptable to a pool having a vinyl liner, structurally sound regardless of size, easy to assemble, consistent in size, and cost-effective.

A stairway includes a one-piece fiber reinforced plastic base having a plurality of riser surfaces and tread surfaces forming steps and a landing surface. The tread surfaces and the landing surface are configured to include an integral reinforcement surface region extending along a length of each tread surface and the landing. A preformed plastic tread member is fastened on a respective one of the tread surfaces of the base, and a preformed plastic landing member fastened on the landing surface. The base includes a front wall region, first and second side wall regions and a rear wall region integrally formed as one-piece and includes an outer filled resin layer and a plurality of fiber reinforced filled resin layers.

Improved mounting elements, mounting arrangements, and methods of mounting liners to structures, such as stair assemblies, in pools and spas are disclosed. One aspect is a mounting element for retaining at least a portion of a liner to a structure of a spa or pool, the mounting element including a face plate and a gasket mounted to the face plate. Another aspect is a mounting arrangement including a gasketed mounting element comprising a face plate and a gasket mounted to the face plate and means for mounting the gasketed mounting element to a structure wherein the liner is secured. Another aspect is a method of mounting a liner to a structure of a pool or spa. The invention facilitates the assembly of pools and spas by reducing the number of individual parts required and minimizing the potential for damaging the liner compared to prior art arrangements and methods.