Replies

1. 
   BossHog | Jun 20, 2002 08:54pm | #1

   Three options come to mind. None of them are easy.

   First - Ceiling joists sloping up to a rige beam. You'd probably have to block up to the rafters to support the high end of them.

   Second - Tear off the roof and drop in scissor trusses. Not a good idea unless you need to mess with the roof anyway.

   Third - Two piece (Field spliced) scissor trusses. Could be put in from below and spliced in place. Really, really labor intensive. May not work depending on how big the span is.

   How big is the room you're dealing with? That info might net you some more useful answers. Glad to hear your back is better.

   Puritanism is the haunting fear that someone, somewhere, may be happy.

1. 
   Redfly | Jun 20, 2002 10:37pm | #2

   Why mess with scissor trusses?  why not just put a beam under the ridge and post  down to the plates at each end (may need to continue down to foundation)?  course then you have a beam exposed at the ridge (you could furr over to the rafter line at the bottom of the beam and end up with a flat ceiling at the top of the vault..........)

   just a thought

1. 
   BossHog | Jun 20, 2002 11:43pm | #3

   Sticking a beam in may or may not work, depending on whether the room is 15' wide or 40' wide. And there may not be bearing available at the ends of the room.

   I never said scissor trusses were a great idea. But if getting bearing for a beam is a problem, they migh be the best solution.

   You idea for using the rafters to apply the ceiling to may or may not work. It depends on the size of the rafters, whether or not he wants ventilation, etc.

   I get enough exercise just pushing my luck.

1. 
   Redfly | Jun 21, 2002 12:16am | #4

   All you say is true.  Also depends on the part of the country, since insulation might become an issue depending on the rafter dimensions.

   I'm trying to picture getting scissor trusses in place without removing the roof and it makes my head hurt. 

1. 
   BossHog | Jun 21, 2002 12:41am | #5

   That'a s why I was saying that field spliced scissors are a pain. But it's POSSIBLE, if there isn't another solution. I don't think I'd want to be the one doing it.

2. 
   TommyB12 | Jun 21, 2002 06:16am | #6

   Field splicing scissor trusses is not that bad.  We did a 24 foot span 32 foot room in about eight hours with two carps.

   The room was at rough frame stage with trusses installed and roof dried in, when the customer requested that the room be converted to cathedral.  There really isn't a need to mess with the roof.  Sister the scissors, and cut out the waste.  Of course you will want to have and engineer spec the gussets/connections where the scissors meet for you.

   It can done cost effectively.Tom

3. 
   JeromeSidley | Jun 28, 2002 04:00am | #7

   Thanks for all the help. I have finally have got to see the room it is 20x20 feet. the rafters are 2x4 what size 2by should I use for the scissors?

4. 
   TommyB12 | Jun 28, 2002 04:17am | #8

   Stubby,

   Why not have the scissor trusses designed by your local truss supplier,  their engineer should be able to do the calcs for you.  There are quite a few unknowns here to be able to give you any specific assistance.  The job might not even be a candidate for the technique I have described.  This isn't something for amateur night.Tom

5. 
   BossHog | Jun 28, 2002 02:24pm | #9

   2X4 rafters are not adequate for a 10' span. You either need to get trusses made, or use bigger rafters and a ridge beam.

   A pessimist's blood type is always b-negative.