Six non-IC can lights have been eliminated in an attic foor, over a kitchen and hallway. Three new Lighting Science Glimpse lights are in this view. All are 3000°K. 6" near and at left. At right rear over a sink, choose 4". All will be dimmed much of the time, and might be left on longer than the poor can lights were. Still the replacement of 65 watt incandescent floods has payback in about two years. The brightness is more than doubled, and much prettier. I like the reveal of ceiling knockdown texture due to large beam angle. I had thought the customer would choose more-efficient Sylvania 70732, 70 lumens per watt, 900 lumens full-on. Their choice of 750 lumens 6" glimpse and 450 lumens 4" Glimpse is instructive. With eight-foot ceilings, 900 lumens in a 4" lens circle is too much. The choice is with sacrifice of efficiency. Glimpse four years into production is still only fifty lumens per watt technology. Why can't Lighting Science do better now, still filling the lower lumens demand, at less than 8 watts?
Know that Glimpse lights are readily available and at price lowered in the past week. For best price and service, consult 1000bulbs.com and LED Lighting Wholesale.
This is my first opportunity to mass-produce patch-in of RACO 175 lighting junction boxes. Cut 7” circles of 1/2” GP Densarmor drywall. Trace a centered junction box. Drill 3 5/8” through the circle center and whittle the rounded corners. The support block consists of two scrap pieces 2x4 @1 3/4” length, 1/2” CDX 1 3/4” wide from scrap of 11” rips, four 1 5/8” deck screws and two 9/16" box-mount screws. The cutting station on a sheet is in the very well lit attic. I set a stop for 1 3/4" cuts on my shop saw and consumed all near odd 2x4 scraps. I used the same 1 3/4" stop to cut the plywood bridges.
This job started out as installation of a clever Calvert USA fire-rated attic ladder. Then comes useful decking not just over the garage but on into a very tall truss attic.
Carve the ceiling drywall to open clearances to 3/32” typical, and spray-wet the annulus.
This is appearance after a third flexible grout application, good enough where nearly all all of the patch will be covered by a 6” LED luminaire. Check out my Flexible Grout: http://plasterrepairhowto.blogspot.com/ . I will supply a free sample, for your project.
Complete full penetration sealing of the patch annulus, and of all junction box openings, with flexible grout, from above.
The table presents payback math employing Brightness Numbers where a standard illumination is that of a 100 watt incandescent, defined brightness B4. The lighting savings are more important than those of associated weatherization, overwhelmingly so if the replaced can light were air-tight IC, and covered with insulation.