Dormer Design & Building Experts on Long Island
Enhance your home with custom-built dormers designed for added space, improved lighting, and timeless curb appeal. NJM delivers high-quality, code-compliant dormer construction for homeowners across Nassau and Suffolk County.
Available for All Residential Dormer Construction Projects
Professional Dormer Construction Backed by Decades of Experience
Whether you're expanding your attic, adding headroom, or creating additional living space, NJM Mechanical and Contracting provides expert dormer construction throughout Long Island, NY. Our licensed and insured contractors bring over 33 years of experience to each project, delivering safe, structurally sound, and seamless additions.
From framing and roofing to interior finishing, we build dormers that blend perfectly with your home while increasing functionality, value, and architectural appeal.
Maximize upstairs space with a shed dormer designed for open layouts, improved lighting, and increased headroom. This versatile style is ideal for transforming attic areas into functional, comfortable rooms with modern comfort.
Classic peaked gable dormers boost your home’s architectural character, improve symmetry, and bring abundant natural light to upper levels. A timeless design that enhances curb appeal while adding valuable interior square footage.
A durable, stylish dormer option that blends naturally with many Long Island home designs. Hip roof dormers add headroom, curb appeal, and weather-resistant strength — perfect for expanding usable space with a seamless architectural look.
Bring your vision to life with fully custom dormer builds tailored to your home’s layout and needs. Whether you’re creating a new bedroom, office, or living space, NJM ensures proper framing, structural support, insulation, and finish work for long-lasting results.
Expert Dormer Solutions Backed
by Over 33 Years of Experience
Why Choose NJM for Dormer Construction & Design...
Expert dormer construction backed by licensed contractors and decades of structural experience.
We operate with full licensing and insurance to ensure safe, compliant dormer additions for all residential projects.
Our team reinforces and frames dormers with precision to guarantee long-lasting strength and stability.
Roofing, siding, and exterior finishes are matched to blend naturally with your home’s existing design.
Proper insulation, ventilation, and high-quality materials ensure improved comfort and lower energy use.
Decades of professional experience mean we install fixtures, piping, and full systems correctly the first time — with workmanship that lasts.
No hidden charges or surprise add-ons. You’ll receive a clear estimate outlining exactly what your installation includes.
Structural Load & Support Evaluation
Assessment of load-bearing walls, roof structure, and necessary reinforcements for safe dormer installation.
Window & Egress Compliance
Verifying dormer windows meet safety, size, and emergency exit requirements for Long Island homes.
Roofline Alignment & Framing Inspection
Precise inspection of framing, trusses, and tie-ins to maintain structural integrity and prevent future issues.
Emergency Siding, Roofing & Flashing Inspectionhut-Off Valve Testing
Reviewing exterior materials, waterproofing, and flashing to ensure long-lasting weather protection.
Insulation & Ventilation Planning
Ensuring proper thermal protection and airflow to prevent moisture buildup and improve efficiency.
Code Compliance & Permit Assistance
Support with building permits and adherence to Nassau and Suffolk County regulations.
Trusted Construction Expertise for Long Island Homes
Our Dormer Safety & Structural Inspection Services Include:
NJM provides comprehensive dormer inspections, structural evaluations, and code-compliant construction services to ensure your addition is secure, efficient, and built to last.
Find Contracting Services Near You!
Service Area Links:
- Long Island
- Nassau County
- Suffolk County
What Our Long Island Clients Are Saying...
Kris
I couldn’t recommend Neil enough! From start to finish him and his team were professional, efficient and experienced. We had a job pulling up rocks and putting top soil down which I know can be a tedious job. We appreciate the work and look
Evelyn Powers
We had an ongoing issue with clogs. My daughter woke up to flooding in her bedroom from her toilet, which was not fun! This was our first time having NJM in our home. Neil was knowledgeable and gave us several options. we chose to have him use the camera to get to the root of the problem. He was able to pinpoint several issues and was able to fix clog and clean out the pipes. Neil and his crew were very professional,
Irene Cheung
I contacted NJM Mechanical because I didn’t have hot water anywhere in my house. Neil was able to diagnose the issue and get to work. My navien tankless water heater is only a year old and still under warranty. Instead of waiting on Navien to send the part so the issue can be corrected, Neil went out, found the part, purchased it,
William Lo
Great experience. Neil came out and took the time to explain everything thoroughly. He was able to fix all the errors on our Navien and have it back up and running. Following up a week later. Neil and Mike came out to redo the Navien system for proper instillation.
Unfortunatley, after there was a gas leak with our Navien system. Neil was able to get
James Farnworth
Neil from NJM was able to get my ac system up and running when others could not. He was honest with me right from the beginning and all costs were discussed before repairs began. Additionally, Neil spent time explaining to me how my system operates and the things I could do to help it run at peak performance. It was quite refreshing to experience a service technician who demonstrated the uppermost
Raul Chardon
Honest professional full of knowledge not BS. Takes pride in his craft and is a master of it.