GMP Construction in Baltimore: Residential and Commercial Roofing with Detailed On-Site Estimates
GMP Construction is a licensed and insured roofing contractor serving Baltimore and surrounding counties, handling residential replacements, repairs, and commercial projects across asphalt shingle, metal, and flat-roof systems.
What GMP Construction actually is
GMP Construction operates as a full-service roofing firm with licensing and liability insurance required for work in Baltimore. The company handles the full scope of residential roof work—from emergency leak repair to complete tearoff and replacement—plus commercial flat-roof and metal-roof projects. Unlike national franchise roofing services or big-box contractor networks, GMP operates as an independent regional firm, meaning decisions and scheduling are handled locally rather than through call centers.
Materials, warranties, and what they install
GMP works with three primary material families. Asphalt shingles (the most common choice in Baltimore, where they account for roughly 85 percent of residential roofs) typically cost between $8,000 and $14,000 for a 2,500-square-foot house, including removal and disposal of old material. Metal roofing runs higher, typically $12,000 to $18,000 for the same footprint, but lasts 40 to 50 years versus 20 to 25 years for premium asphalt. Flat roofing for commercial buildings or additions uses EPDM rubber or TPO membrane, priced by the square foot and confirmed during the site visit.
Warranty terms vary by material and manufacturer. Standard asphalt shingle warranties cover 20 to 30 years for the shingles themselves, though labor and installation are typically warranted separately for 5 to 10 years. Confirm warranty specifics for any metal or specialty material during your estimate.
How to compare GMP to other Baltimore roofers
Baltimore has a dense roofing market. Major chains like Owens Corning and GAF operate through licensed dealers across the region; these outfits often advertise heavily online and field multiple crews. Regional firms like JM Roofing and local one-person operations fall on either side of GMP's scale. Key differences: national franchise networks offer uniform pricing and rapid scheduling but less flexibility on material choices; single-operator roofers are cheaper but often have longer wait times and no backup if the owner gets sick. GMP sits in the middle—established enough to carry full insurance and maintain a crew, but local enough to handle schedule adjustments and custom requests without routing decisions through a regional office. Choose a national brand if you need the work done within 3 weeks and want predictable pricing. Choose GMP if you have a complex roof (steep pitch, multiple valleys, old structural issues) and want someone who can problem-solve on site. Avoid sole proprietors if the job is urgent.
Inspection and estimate process
GMP's estimate process begins with an on-site inspection. A representative climbs the roof (weather permitting) to assess shingle condition, flashing integrity, gutter and soffit state, and any signs of leakage or structural damage. This inspection typically takes 30 to 45 minutes and is free. Photos are taken, and a written estimate is provided, usually within 3 to 5 business days. The estimate breaks down material costs, labor, removal and disposal fees (typically $1,500 to $2,500 for a full tearoff), and any additional work discovered during inspection (rotten decking, cracked flashing, inadequate ventilation). Baltimore requires a permit for roof replacement; GMP includes permit fees in its estimate.
Licensing, insurance, and what this means for you
GMP holds a Maryland roofing license and carries general liability and workers' compensation insurance. Verify both before signing any contract. This protects you legally if someone is injured on your property during the job or if a crew member damages your home. Uninsured or unlicensed roofers are common in Baltimore and undercut prices by 30 to 40 percent, but you assume all liability, and disputes over workmanship have no legal recourse.
Who this service suits and who it doesn't
GMP works best if you own a residential or small commercial property in Baltimore County, need a full roof replacement or repair within 6 to 12 weeks, and want experienced crew work with clear warranties. It suits homeowners who've found shingle damage after a storm or detected leaks inside an attic. It does not suit you if you need emergency 24-hour work (call a local emergency service instead), are shopping purely on price and willing to hire an unlicensed contractor, or own a large commercial property requiring a competitive bid process and architect approval.
Hours, contact, and logistics
GMP operates Monday through Friday, 7 a.m. to 4 p.m., with scheduling for inspections typically available within one week. On-site work begins early morning to allow for material delivery and crew setup. The company does not offer emergency night service; after-hours leaks should be tarped temporarily by the owner or a 24-hour emergency service. Parking for work trucks is required at your address; if street parking is not available, discuss access before the job starts.
GMP Construction fills a practical role in Baltimore's roofing landscape: experienced enough to handle complex jobs, established enough to warrant its work, and local enough to respond to scheduling needs without franchise-level delays.
