Garage Rafter Issue / Flourescent Lighting

[bestonearound]

Bought a house built in 1968. Previous owner had a grow room in the garage. I tore it down. It is an attached garage (20x23) with a slightly sloping roof (maybe 4 feet at peak, that peaks parallel with the 20 foot side in the middle.

The entirety of the garage is drywalled but there are holes, nails, screws...everywhere....I mean everywhere. The lesser of two evils (time wise) is to tear down all the drywall and put up new stuff.

I have a bunch of 2x4 Flo lights I intended on flush mounting with the new drywall. It's only 8 foot ceilings. I found the rafters (2x8's) in the ceiling, however are mounted every 12 inches (strange).

My question is: Can I notch out the applicable rafter enough to put the light flush, and if I have to brace the rafter with some sort of metal bracket (makeshift gusset) without compromising the integrity of the roof? At some point, someone put one of the those pull-down, fold-out ladders in the ceiling by cutting the joists and bracing them against adjacent joists thereby creating a hole 24 inches wide for a span of 57 inches and the thing hasn't collapsed....why I don't know because there's almost no room up there for storage.

Height of the Flo lights are 5 1/2".

 

[Boomer343]

Why not run the lights parallel to the rafters?

If it was mine and I wasn't using the existing stairs I'd reframe the opening properly.

Short answer is you can't cut out 5 1/2 inches of a 2 x 8 and micky mouse a fix around it.

Good luck....

 

[Falcon67]

If the stair was put in with the proper headers, then the loads are being handled correctly. That's SOP for attic stairs. I would not notch rafters for any reason. You need every inch of that 2x8 for the span.

 

[bestonearound]

Why not run the lights parallel to the rafters?

These are 2 foot by 4 foot lights. The rafters run every 12 inches. So I would have to remove or notch out one to mount parallel. I am trying to do just that. I just want to do it as close to right as possible.

So is my only closest-to-right option to cut out a rafter and brace the ends with joist hangers to adjacent rafters (creating a box) for the light to go into?

 

[Steevo]

No. You can't cut rafters like that. In fact, are these rafters (roof surface is on top of them), or are they ceiling joists? When they have to make an opening, such as with an attic entrance or stairway, the joists on either side are doubled for their entire length, in order to distribute the load that the missing span would have supported. Unfortunately, the only way to flush mount lights in your garage is to buy narrower lights, or switch to can lights.

 

[bestonearound]

Ceiling joists, not rafters then. Sorry.

I just see every 12" as overkill. That's why I ask.

I'll have to map out my joist layout with Smartdraw or something. They don't run the full length of the garage. It kinda looks like someone added on, but it's hard to tell. Once I get it mapped out, I'll post that up and reevaluate.

 

[Steevo]

It would be a good idea to remove all of the ceiling sheetrock and verify the construction then. Maybe someone added joists between the original ones, which may have been at 24"" o.c. That is an expensive way to provide nailers for sheetrock though.

 

[bestonearound]

Okay, will do. My only sight right now is from the small area in the attic looking down. I plan on removing all the drywall in the next few days. I'll watch for alterations.

 

[Falcon67]

>I just see every 12" as overkill. That's why I ask.
Standard building technique. Typical span tables list lumber sizes based on 12", 16", 19.2" and 24" on center use. Western lumber span table lists SPF #2 2x8 (common stuff at HD/Lowes) as good for 22' 8" span at 12" OC. 10 lbs live load, 5 lbs dead load (basic sheetrock ceiling). Change that load to 10 lbs dead load and that lumber is good to only 19' 10". Devil lives in the details, as always.

 

[Boomer343]

Bestone my coffee hadn't kicked in this am...I was thinking 2 light units 4 feet long...and you are using units from suspended ceilings 2 x 4 in size .....

I have switched over to the new small diameter bulb flouresent fixtures as the light tubes are easier to find and cheaper. You might want to see if the time and effort is worth it for the 2 foot by 4 foot fixtures you have.

I'll try to do better tomorrow....maybe a little kalua in the coffee would help.