Replies

1. 
   Guest_ | Sep 20, 2000 05:33pm | #1

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   Just a guess but those 2x6 'joists' may be collar tes. Do you have gabled ends? In any case, I'd just leave 'em, and work the new joist layout around them. I just went & did a search on "joist span tables' at MSN.com, and...

   It depends on your loads and the grade of lumber. There are three sets of circumstances: ceiling joists, attic floor joists, and normal floor joists.

   b Ceiling joists;
   Table 9 Ceiling Joists – 20 psf live load, 10 psf dead load, 240 deflection; Drywall Ceiling; No Future Room Development, But Limited Attic Storage Available

   2x10 @ 16" centers gets you 15'8" to 25'5" depending on grade.

   b Attic floors:
   Table 1 Floor Joists – 30 psf live load, 10 psf dead load, 360 deflection; Sleeping Rooms and Attic Floors

   2x10 @ 16" centers gets you 13'7" to 19'5" depending on grade.

   b 'Normal' floors:
   Table 2 Floor Joists – 40 psf live load, 10 psf dead load, 360 deflection; All Rooms Except Sleeping Rooms and Attic Floors

   2x10 @ 16" centers gets you 12'2" to 17'8" depending on grade.

   So, unless your usage comes under 'Ceiling joist', and I doubt it does, I think you'll need to go to additional support or engineered joists. I'm thinking you'll come under 'Attic floor', and if it were me, I'd probably want the 'normal' floor rating anyway - provide for future use, ya know? A 14" or 16" deep I-joist should work nicely, though, depending upon grade/manufacturer/etc.

   Look at Southern Pine Council for the span tables, Boise-Cascade Engineered Products for I-joist information. Other manufacturers are available and may differ, I just found this easiest to use for 'typical' reference. Check with your suppliers for all info, and take what I say with a grain of salt, thus endeth the disclaimer.

1. 
   Guest_ | Sep 20, 2000 06:50pm | #2

   *it's hard to beat one lally column right in the center with a built-up beam for supporting the 2d floor of a 24 ft. garage.....now your span is down to about 11 ft.. and the possibilities are numerous...

1. 
   Guest_ | Sep 20, 2000 07:03pm | #3

   *Im with Mike. One column in the middle and you could store your antique anvil collection up there.There might be one alternative though. I've seen where a 2x6 is run vertically from the ridge beam to a built up beam which the joists rest on. Essentially the beam hangs from the ridge instead of supported by a column. Obviously there are some roof framing issues involved but me thinks you get the idea.

2. 
   Dan_Yocum | Sep 22, 2000 01:26pm | #4

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   Yea, everybody has been telling me the best/cheapest/fastest way is to put one column in the middle. The issue I have with that is that its usually right opposite where a car door would open!!

3. 
   Guest_ | Sep 22, 2000 05:17pm | #5

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   do what you want.... it doesn't get in the way any more than the wall where the other door opens..

   but it's your garage...

   my customers usually go for the lally column when i 'splain the alternatives..

1. 
   Guest_ | Sep 23, 2000 05:05am | #6

   *Dan,Go to the lumberyard/truss manufacturer of your choice, and look into engineered floor trusses. You just might have the headroom to sneak in a top chord bearing floor truss. I'm assuming your keeping the old roof intact, you'll have to verify that you'll have adequate bearing on the walls below. Note your existing wall framing, and construction. Do you have a double top plate? Your 2"X6" "ceiling joists" sound like collar ties to me, and I'd be leary of removing them, but you probably want to do so for headroom?? I guess we need more specifics on the garage, but the top chord bearing floor trusses may solve your not wanting a post dilemma. Also if pursuing trusses, they'll want to know what your storage intentions are for that floor, so a suitable truss can be used.Best,J.R.

1. 
   Guest_ | Sep 23, 2000 05:59pm | #7

   *Dan, I assume you want to build a floor system to replace the 2x6's, that are placed on top of the wall plates.If this is the case I think you might like a built-up lvl beam (no posts, 2x8 joists, and the subloor of your choice.A couple of years ago I finished the attic area of a 24x24 garage. The existing floor of the attic was 2x10's spanning 24' without a beam, with a layer of 1/2" ply. The owners were using it for storage, but it wasn't pretty and I don't think you would be happy with it. The engineer spec'd 3 - 1 3/4" x 18" lvl's for the proposed load, but I would be surprised if you couldn't do what you want with 2 - 1 3/4" x 16" beams. They are about $5.50/ft, so 48' x 5.5 = $264.00. Go to a real lumberyard and have them spec up up what you need for your load.As for the post debate, I would never put a post in a garage. New construction install a steel beam, existing install lvl's. The extra cost for the beam is pennies over the life of a house, err...and I just hate posts in a garage. Also, lvl's are wicked slick to install in a remodel. They are light enough for two people to handle and flex enough to fit between two walls.Also, string your walls and see how messed up they are, I suspect they might be a little less than perfect, especially the gable ends. If you decide to continue with this project take the time to get them right.

1. 
   Guest_ | Sep 24, 2000 03:09am | #9

   *Dan,Couple of things you did not tell us. First is roof pitch and the second is what you plan to store up there. Roof pitch is important because a 4/12 or 5/12 pitch is not going to give you very much useable space for your investment in time and materials. A storage shed might be a more cost effective option. What you plan to store is important because light storage may be doable and heavy items are most likely out of the question. If you have heavy stuff again, consider a shed.One option that has not been discussed is turning your existing rafters into simple trusses. To do this you would need to run a joist at every rafter pair. The rafters should be connected to the joists with a 2x4" leg. Face nail the leg to the rafter and use a pair of plywood cleats where the leg meets the joist. I would divide the joists into thirds. Spot the legs on the marks and run them vertically to the rafters.You should be able to deck the center third and use it for light storage. No pianos. But the Christmas decorations and the boxes of paisley neck ties and bell bottom jeans you are saving for the Smithsonian should be OK.Steve

4. 
   Dan_Yocum | Sep 24, 2000 03:09am | #8

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   I have a 24ft square garage. Currently there are six 2x6 "ceiling joists" tieing the garage walls together. Obviously the ceiling area is open.

   I would like to convert this to storgage area. Can I do this without adding a beam or posts? I was thinking of removing all of the 2x6's and running 2x10's on 16 centers. Will this work? Are there any other options?