Aluminum Thermally Broken Curb Mounted (ATCM) – Roof Access

This model consists of a durable, weather resistant, extruded aluminum retaining frame and an extruded thermally broken aluminum heliarc welded base frame. The aluminum base frame is thermally broken, preventing the passage of cold air from the exterior to the interior light shaft.

The ATCM roof access skylight is hinged directly to the curb and does not include a two part sash and base. The entire skylight lifts off the curb and is sealed to the curb with a high density foam gasket when closed. This skylight does not include a screen and is primarily used for roof egress applications.

The roof access skylight includes a pull bar, locking latch and hydraulic gas cylinders that support the skylight when in the open position.

The Columbia aluminum thermally broken curb mounted skylight is designed to work on any height curb with a nominal 2” width.

Wide range of glazing options in both glass and acrylic»

Suitable for all flat or sloped roof applications»

Standard sizes include a full range of models for homes designed with 16” and 24” on centre rafters or trusses.»

Any size skylight available»

Exterior frame finishes – four standard colours»

Flashing system»

Large capacity four sided condensation channel»


a. Glass

  • Clear
  • LoE³ Clear
  • LoE³ Neat
  • LoE³ Triple Glazed
  • LoE³ Bronze
  • Solar Reflective Bronze
  • Heat Mirror 44
  • Laminated option

All above standard tempered / tempered sealed units

Each option available with interior pane in laminated — clear or white

Any other glass options, including grey, blue, green etc in plain or coated glass are available

b. Acrylic

  • Clear
  • Bronze
  • White

All above available in single, double, or triple glazed

c. Polycarbonate

  • Clear
  • Bronze
  • White

All above available in single, double, or triple glazed

See Glazing section for additional information.

  • Glass – Installs on roofs with minimum 2:12 slope (15 degrees)
  • Acrylic – Installs on flat or sloped roofs
  • Polycarbonate – Installs on flat or sloped roofs

See Roof types and slopes section for additional information.

See Why Skylights – What Size section for additional information.

  • Glass available in 22 standard sizes from 16” x 48” to 36” x 48”
  • Acrylic and polycarbonate available in 27 standard sizes from 16” x 48” to 48” x 48”.
  • Any custom size in glass or acrylic also available. Example – inside curb rough opening 17¾” x 56½”.

  • Standard frame colour – Rideau Brown
  • Optional frame colours – Black, White, Sandalwood
  • Custom coloured frames also available

  • Flashing kits available for sloped applications only
  • Suitable for shingles and other low profile roofing materials
  • Use in conjunction with roofing membrane for superior seal
  • Custom flashings are required for flat roofs and other roofing materials

  • Weep holes allow any condensation build up to drain to the outside roof
  • Allows for multi directional installation of skylight. Direction must be specified when ordering.
  • Eliminates water stains on your interior light shaft

  • Comprehensive 20 year warranty on insulated glass, and 10 years on the skylight
  • Hydraulic gas cylinders have a 2 year warranty

See Warranty section for additional information.