Specification guides.

Specifying trimless lighting well means fixing the details that decide how a scheme looks and performs long after handover: output and efficacy, optic and beam, glare rating, colour temperature and rendering, finishes, drivers and controls. These guides set out what to put on a specification, what to ask suppliers for, and where substitutions usually creep in. They are written by the 299 Lighting technical team from the questions architects, interior designers and M&E engineers ask us on live projects.

What these guides cover

• What to include in a trimless lighting specification and schedule
• Performance data to request: photometry, UGR, CRI, lifetime and warranty
• How to protect the design intent at tender and value engineering

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All specification guides

• Trimless linear lighting: a specification guide — Trimless linear lighting is specified by profile, length, output, optic, colour, controls and installation details, made to measure to the ceiling plan.
• Glare control in trimless lighting — Trimless lighting glare depends on the optic, not the trim; use microprismatic or deep-set optics and confirm UGR with room calculations.
• Colour temperature and CRI for trimless lighting — Trimless lighting typically uses 3000K to 4000K with CRI 80 to 90+, chosen to suit the space, finishes and use.
• BIM and CAD details for trimless lighting — Trimless lighting needs BIM objects, CAD sections and photometric files so the design team can coordinate ceilings, services and lighting performance.
• Why trimless lighting mock-ups matter — A trimless mock-up confirms the finish, light quality, plastering detail and sequencing before full installation, avoiding costly mistakes.