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One Call, Not Ten

Most construction problems happen in the gaps between trades, where one contractor waits on another and no one owns the delay. We close those gaps by keeping construction, mechanical, electrical, plumbing and specialized work under a single team. For a facility manager or a government client, that means one accountable partner, one schedule to track, and one company answering for the result.

Where Mistakes Are Not An Option

The clients who trust us work where errors carry real consequences: federal facilities, pharmaceutical plants, and industrial sites that cannot simply shut down. That work demands documentation, safety compliance and precision that not every contractor can meet. We have built our reputation in exactly those environments across Puerto Rico, and we hold every project to the standards those clients require, whatever the size.

Built On Repeat Business

A contractor is only as good as the next call from a client who already knows the work. We have grown by earning that call, through professionalism, integrity and a straightforward way of doing business that keeps clients coming back. Many of our projects come from people we have worked with before, or from those they recommended. That trust is something we protect on every job.

Douglas M. Rivera Cuevas | President & Mechanical Engineer

Capstone Mechanical & General Contractor LLC is led by its President, Douglas M. Rivera Cuevas, a mechanical engineer who founded the company in 2017 as Hurricane Maria approached Puerto Rico. In the months that followed, he built the firm around the island's recovery, taking on the construction, mechanical and industrial work that communities and facilities needed to reopen.

Since then, Douglas has directed projects across the federal, government, pharmaceutical, educational, commercial and industrial sectors, bringing an engineer's discipline to project management, budgeting, contract administration and risk management. That technical grounding is why the company self-performs so much of its mechanical, electrical, civil and specialized work rather than handing it to others. Under his leadership, Capstone Mechanical & General Contractor has grown into a full-service contractor known for quality, safety and reliability on every project.