Modern HVAC systems live or die on details: airtight seams, correct transitions, flat flanges, compliant insulation, and components that actually fit once they reach the roof or mechanical room. Off-the-shelf duct or curb hardware often forces installers to “make it work” on site—costly time that risks leaks, vibration, and callbacks.

3D Vector solves this with custom sheet metal fabrication designed specifically for HVAC contractors, OEMs, and facility teams. From laser-cut blanks to fully insulated, gasketed assemblies, we deliver production-quality parts engineered to SMACNA best practices and tailored to the realities of field installation.

What We Fabricate

We build single components and complete kits, labeled and ready to install:

  • Rooftop curb adapters (pitch-correcting, insulated, gasketed; with lifting points and knockouts)
  • Custom plenums (supply, return, and mixed-air), straight or offset, single-wall or double-wall
  • Transitions & offsets (square-to-round, eccentric, lateral, tapered, with turning vanes as required)
  • Rectangular & round duct (TDC/TDF, S-&-drive, Pittsburgh, spiral, and welded)
  • Equipment bases & frames (fan/filter racks, coil housings, and rooftop equipment stands)
  • Drain pans & drip trays (stainless or coated, sloped with threaded outlets)
  • Hoods & cowls (intake, exhaust, and louvered assemblies with bird-/insect-screen options)
  • Access doors & service panels (double-wall, insulated, hinged, or tool-release)
  • Acoustic & thermal enclosures (lined, vibration-isolated, with removable sections)

Materials We Use and Why

Choosing the right metal and thickness is fundamental to performance:

  • Galvanized steel (G60/G90): The default for most rooftop and duct components—great corrosion resistance and value.
  • Aluminum (3003/5052): Lightweight with excellent corrosion resistance; ideal for coastal installations and large covers.
  • Stainless steel (304/316): Hygienic, chemical-resistant; used for drain pans, food-grade spaces, and harsh environments.
  • Aluminized steel: Heat and corrosion resistance around high-temperature exhaust.

Typical gauges (guided by size, span, and pressure class): 24–22 ga for light duct sections; 20–18 ga for curb bodies and plenums; 16–14 ga where spans are long or loads are high. We size stiffeners and hemmed edges so the finished assembly stays flat and rigid during handling and after anchoring.

Fabrication Processes

3D Vector combines digital precision with shop-floor craftsmanship:

  • CAD/CAM & nesting: We accept DWG/DXF/STEP models and generate cut programs that minimize scrap.
  • Laser cutting & CNC punching: Clean edges, accurate holes and knockouts, repeatable tabs and alignment features (as seen in your laser-cut post fixtures).
  • Forming & rolling: Press-brake forming with tight bend radii; roll-forming for cylindrical parts and gentle tapers.
  • Joining: Pittsburgh and snap-lock seams, TDC/TDF flanges, spot welding, MIG/TIG welding, rivets, and clinching, depending on load, seal, and appearance requirements.
  • Sealing: Butyl and urethane mastics, pre-applied gaskets (EPDM/neoprene), and sealant beads in hidden seams for airtightness.

We deburr all cut edges, knock down corners, and add stiffening beads or hat channels where spans require greater rigidity.

HVAC Insulation

Insulation, Liners, and Thermal Breaks

Thermal and acoustic performance is often as important as airflow:

  • Internal liners: Fiberglass duct liner (1″–2″, 3–6 lb density) with antimicrobial facers for supply and return plenums.
  • Board insulation: Foil-faced polyiso or mineral wool panels for curb walls and housings; mechanically fastened or adhesive-bonded.
  • Closed-cell elastomeric foam: Where moisture resistance matters (condensate, cold decks).
  • Double-wall assemblies: Solid or perforated inner liners with outer sheets and an insulation airspace.
  • Thermal breaks & isolation: Non-conductive spacers, vibration isolators, and gasketed flanges to cut noise paths and sweat.

We align insulation specs with project goals, temperature control, sound attenuation, condensation management, or code compliance.

Finishes and Corrosion Protection

Environment and appearance drive finishing choices:

  • Mill galvanized or aluminized: The economical default.
  • Powder coat: Durable, uniform color (any RAL), ideal for visible rooftop equipment and indoor architectural plenums.
  • Hot-dip galvanizing: Extra corrosion protection for structural outdoor hardware.
  • Stainless passivation & brushed finishes: For sanitary or corrosive settings.
  • Sealants & clear coats: On cut edges or inside curb bodies to extend service life.

We also apply PEMs and threaded inserts where field disassembly or service panels are needed, maintaining the finish and saving installer time.

Engineering to SMACNA Best Practices

Airtightness and structural integrity are non-negotiable. Our designs follow SMACNA and common ASHRAE recommendations for:

  • Leakage classes & pressure ratings appropriate to the system (UL 181/ASTM E84 equivalents can be supported where specified).
  • Deflection limits on long spans, reinforcing with formed flanges, channels, and angles.
  • Access & service clearances for filters, coils, and fans.
  • Drainage (pitched pans, threaded outlets, weep holes where needed).
  • Safety (hemmed edges, rounded corners, lift points).

Every job includes QC checkpoints: dimensional verification against CAD, flange flatness checks, dry-fit of mating pieces, fastener sampling, seal continuity, and, if requested, shop leak testing before shipment.

HVAC metal fabrication

Spotlight: Custom Curb Adapters

Replacing a rooftop unit rarely aligns perfectly with the existing curb. 3D Vector curb adapters are built to solve that mismatch:

  • Pitch-correcting frames keep equipment level on sloped roofs.
  • Insulated, foil-faced walls improve thermal performance and reduce condensation.
  • Gasketed top flanges speed the set and help achieve airtightness with minimal field sealant.
  • Integrated rails & stiffeners maintain flatness for equipment gasket compression.
  • Knockouts & access windows for electrical and controls, sized and located from your submittals.
  • Lifting eyes and handling pockets (as shown in your photos) to make crane picks predictable and safe.

Adapters arrive kitted, labeled, and ready to bolt up with the hardware package you specify. Where constraints are tight, we design knock-down sections that assemble on the roof with alignment tabs and pre-punched holes.

Design for Manufacturability (DFM)

Getting the design right upstream saves hours on site. Our engineers collaborate with your team to:

  • Verify airflow areas, transitions, and offsets so pressure drop stays in spec.
  • Add slotted holes for adjustability and locator tabs for one-way assembly.
  • Choose seam types that balance cost, rigidity, and airtightness.
  • Define service access (hinged doors, removable panels) for future maintenance.
  • Provide shop drawings and 3D views for field approval before we cut metal.

We work from CAD, markups, site dimensions, or laser scans and can mirror or revise older parts when drawings are unavailable.

Digital Traceability, Kitting, and Packaging

Installation is faster when parts are easy to identify:

  • Itemized BOMs with matching labels on every piece
  • QR codes linking to drawings or installation sheets
  • Hardware kits bagged by sub-assembly
  • Protective packaging (edge-guard, foam, shrink, and skids) suitable for rooftop craning and job-site handling

Assemblies ship in the order you’ll set them, so crews can stage and install without hunting.

Where Custom Fabrication Adds the Most Value

  • RTU changeouts & retrofits: Adapters and transitions that minimize roof penetration changes and downtime.
  • Data centers & labs: Tight leakage targets, double-wall plenums, and acoustic enclosures.
  • Healthcare and pharma: Stainless drain pans, smooth liners, cleanable access.
  • Food & beverage: Wash-down-ready housings and hoods.
  • Large commercial & institutional: Long runs of consistent, labeled duct components that reduce rework.

Specifying a Job: A Practical Checklist

To quote and fabricate accurately, the following details keep projects moving:

  1. Component type (curb adapter, plenum, transition, duct, hood, pan, enclosure)
  2. Unit make/model and connection sizes/locations (supply, return, OA, exhaust)
  3. Site conditions (roof pitch, curb height, clearances, crane limits)
  4. Air volume & static pressure (guides pressure class and seam selection)
  5. Material & finish (G90 galvanized, aluminum, stainless; powder coat color if required)
  6. Insulation & liner (type, thickness, facing; double-wall or single-wall)
  7. Sealing (gasket material, mastic preference)
  8. Hardware preferences (TDC/TDF, S-drive, nuts/bolts, PEMs, captive fasteners)
  9. Packaging & labeling needs (kitting, QR, install order)
  10. Submittals (shop drawings, 3D models) and any test/inspection requirements

If you’re replacing legacy equipment, a few photos and rough dimensions are often enough for us to draft a starting concept and validate fits before fabrication.

Sealing gasket material

Why HVAC Teams Choose 3D Vector

  • Precision: Laser-cut parts, consistent bends, and flat flanges that seal without wrestling.
  • Speed with control: A digital pipeline from CAD to cut allows quick iterations while keeping revision control tight.
  • Installer-centric design: Slotted holes, access panels, and labeled kits reduce rooftop time.
  • Quality assurance: SMACNA-driven designs, documented inspections, and optional leak checks.
  • Flexibility: One-off prototypes, matched replacement parts, or coordinated production runs.

From Cut Sheet to Set-and-Seal

Whether you need a single curb adapter or a complete mechanical-room package, 3D Vector’s custom sheet metal fabrication keeps your HVAC projects on spec and on schedule. We combine accurate digital models, clean fabrication, and installation-ready details so your crews can lift, align, fasten, and seal without field improvisation.

Bring us your drawings or dimensions, and we’ll turn them into metal that fits the first time.