ECN Forum Forums Code Related Discussion NEC & other Code issues Drop Ceiling Lighting

There is an unstated need for height when using T grid.

Whenever I've encountered it in homes, it's always in a DIY basement 'upgrade' designed to use storage space for a game room or such.

The T grid was chosen to cover the ugly -- normally plumbing and HVAC runs.

The remaining height is too low for lay-in troffers / can lights.

Instead the solution taken was T-bar wrap fixtures surface mounted. These throw light all around and are cheap, cheap, cheap.

The one time I saw lay-ins the lighting was a terrible gloom of too bright and too dark. Rather like an interrogation setting behind the Iron Curtain.

Tesla,

I just inspected a job with the shallowest lay in fixtures I have ever seen. They couldn't have been more than 2" high. The need was because too much junk above the grid. Pipes, duct work, etc. The EC said that the fixtures were expensive, but they fit the need.

Well, so far you're all on target.

The drop ceiling folks do include specifications for minimum space above the grid - I think it's 5" - in their instructions; but, as has been noted, we're talking about ceilings installed by DIY's and other unprofessional folks.

There is at least one troffer made that is no thicker than the grid - call it 1-1/4".

I was referring to the lenses sold at the home stores fitting in the grid, but your needing to trim them to use them as a replacement lens for a troffer.

The two places I tend to see these are basements - to hide all the ceiling clutter - and kitchens.

The strip fixtures are invariably 'cheap, cheap, cheap.' Cheap even by strip fixture prices. Yes, their install often violates the instructions (some call for a clearance, to not be flat against the ceiling), and have flexible cord connections (a question of 'when' as to that being a code violation).

I didn't want to get bogged down in all those details. It appears that there is no code rule against the basic idea of using strip lights and independent lenses.