With the national economy seemingly getting softer by the day, one Lawrence-based company believes it has found a solid product to rest upon — concrete floors. Prosoco — which has its headquarters and manufacturing plant in the East Hills Business Park — has begun a $300,000 remodeling of its plant to give it more capacity to produce products for finished concrete floors. Among the several products Prosoco produces are stains, finishes and hardeners for concrete floors. In a down economy, that has ended up being a product line with an upside, said Gary Henry, a spokesman for the company. “In a contracting economy when everybody is looking at every conceivable way to save a buck, finished concrete flooring is looking better and better,” Henry said. Almost all commercial buildings have concrete floors, but in the past, office buildings, churches and other types of large users have usually covered the concrete with carpet, tile or wood flooring. Now, builders are realizing there are cost savings to be had by simply finishing the concrete with a colorful stain and a high sheen gloss. The remodeling project at Prosoco will increase the company’s warehouse capacity for the concrete finishing products by about 65 percent. The work also will include the construction of a new loading dock to allow the necessary raw materials to manufacture the products to be shipped in more easily. The project has had a small impact on jobs. The company in the last month added two new employees to its Lawrence operations to help keep up with increased demand. The company now employs 65 people at its Lawrence plant and headquarters facility.