JonMas Construction is a family-run general contractor serving St. Louis and the surrounding area. From whole-home remodels to small fixes, we show up, do the work, and leave the place better than we found it.
We're generalists by trade and specialists in showing up. Here's what we're hired for most.
End-to-end renovations — design, demo, build, and finish. One crew, one timeline, one point of contact.
Cabinetry, tile, plumbing, fixtures. The rooms that sell a house, done with care for the rooms you live in.
Mother-in-law suites, sunrooms, second stories, basement finishes. We handle permits and engineering.
Drywall, trim, paint, flooring. The detail work that makes a room feel finished, not just done.
Composite and wood decks, railings, siding, and exterior repairs that hold up to St. Louis weather.
Got a list of small things that have piled up? We knock them out in one or two visits — no minimum.
Every project starts with a conversation about the space, the budget, and the timeline. Here's what those conversations turned into.
We work on a handful of projects at a time so each one gets real attention. Want to walk through one in person? We'll set it up.
We stay close to home — usually within a 30-minute drive. That means quick site visits, faster response when something comes up, and a crew that knows the local code officials by name.
Don't see your neighborhood? Give us a call — we travel for the right project.
The bar to call yourself a contractor is low. We hold ourselves to a higher one.
Free estimates, no pushy sales pitch. We'll tell you straight up if we're the right fit — and recommend someone if we're not.
Fill out the form or give us a call. We typically reply within one business day.