For over 20 years, MJ Monahan Builders has been building and renovating on the Main Line and Suburban Philadelphia. Founded in 1990 by Mike J. Monahan, project-by-project, MJ Monahan Builders has established themselves as premier builders grounded in integrity, quality and service.

MJ Monahan Builders has made their mark with consistently superior construction. We are 100% committed to
meeting our clients’ expectations and achieving project goals with speed and quality.. in

Areas of expertise include Residential, Custom Homes, Additions Renovations and Historic Restoration.

MJ Monahan Builders has won numerous industry awards as well as back-to-back “Best of the Main Line” for construction in 2009, 2010 & 2011. We feel this speaks to our level of excellence and service as well as our commitment to our community.

Please contact Mike at for more information or to schedule an appointment to discuss your project.



  • MJ Monahan Builders - Devon, PA -  dumfounded

    Reviews: 1

    Worst builder!
    dumfounded (1 review)

    This builder is very unprofessional - does not return calls, texts, emails. Is extremely unorganized and unreliable. Does not show up for preset mtg times and if he does, he's late and only stays a short while so problems don't get resolved. Only makes himself available when payment is due and then disappears for days on end. Does not complete work that has been paid for. Hires below par subcontractors who are unprofessional and do poor quality work. Does not oversee the project so workers are flying by the seat of their pants. Project sits for days on end with nobody showing up to work. Does not repair or replace damage caused to your home even though he "promises" to do so.

    More »

    Was this review helpful?

    (0) (0)

Business details

Services & Repairs

  • Basement Remodeling
  • Bathroom Remodeling
  • Estimates
  • General Repairs
  • Kitchen Remodeling
  • Remodeling & Renovation
  • Restoration
  • Room Additions