scissor trusses - Contractor Talk - Professional Construction and Remodeling Forum

paulie · 08-11-2009, 08:16 PM

Looking for a "easier" solution for a customer to change a roof line. I would like to tear off and start from scratch. HO asks, can I just go over the existing roof. I say let me think about it. One week later all I can think of is scissor trusses. Is it do-able? Trying to figure how the fascia will work. The house is 36' X 36'.

Some pics:

Warren · 08-11-2009, 08:18 PM

Which end are you changing? We have done that a few times with stick in rafters, and a few other times with modified scissor trusses.

paulie · 08-11-2009, 08:22 PM

Sorry, the living area. If you're looking at the head on pic, the right side.

Warren · 08-11-2009, 08:27 PM

Gonna have to raise up that chimney and that pvc stack. Consider how you are going to vent the roof also. Be sure to cut a nice wide strip off of the existing BEFORE you set the trusses and sheath it. Or else someone will have to drawl up there later and do it. We did one once where we increased a pitch from 2/12 to about an 8/12 using rafters. Created a space in there that was big enough to stand up in. We installed an access stair and homeowner had great storage area. Little slope to the floor but fine for misc storage.

Warren · 08-11-2009, 08:28 PM

Engineering is probably gonna require that you remove some roofing at the bottoms to be able to set the truss on the existing wall. Might be able to remove top piece of siding and install the hurricane clips on the outside of the wall.

paulie · 08-11-2009, 08:37 PM

Wondering about the soffit.

Warren · 08-11-2009, 08:46 PM

Paulie: With a little luck, you can probably remove the soffit and reuse the panels if they are in good shape and cost is an issue. Your trusses can be made to plane out to the same fascia height. Of course your gonna have siding and trim on those gable ends to do also.

paulie · 08-11-2009, 08:54 PM

Quote:

Originally Posted by Warren

Paulie: With a little luck, you can probably remove the soffit and reuse the panels if they are in good shape and cost is an issue. Your trusses can be made to plane out to the same fascia height. Of course your gonna have siding and trim on those gable ends to do also.

Guess I'm being pretty vague tonight, sorry. I was worried about ending up at the existing fascia. It's just such a huge soffit panel, which I've found is more cost effective to just rip and put new up. Those weird recesses at the rear corners throw me. But I'm going to pursue it tomorrow and start pricing and engineering.

house bldr · 08-11-2009, 09:11 PM

I have done it by removing the bottom row of sheathing and cutting the new rafter to a point on the bottom and setting it right on top of the existing rafter just inside the fascia board, no need to mess with the fascia or soffitt.Then cut some blocking in over the wall to transfer the load off the old tails and down to the wall.This will leave a goofy looking double gable on the ends unless you cut it back and reside the gable ends.

Warren · 08-12-2009, 04:44 AM

Quote:

Originally Posted by house bldr

I have done it by removing the bottom row of sheathing and cutting the new rafter to a point on the bottom and setting it right on top of the existing rafter just inside the fascia board, no need to mess with the fascia or soffitt.Then cut some blocking in over the wall to transfer the load off the old tails and down to the wall.This will leave a goofy looking double gable on the ends unless you cut it back and reside the gable ends.

And how do you install any kind of hurricane strapping?? If your gonna go so far as to expose the existing rafters/wall, why would you not set the truss/rafter directly on the wall?

house bldr · 08-12-2009, 06:42 PM

Quote:

Originally Posted by Warren

And how do you install any kind of hurricane strapping?? If your gonna go so far as to expose the existing rafters/wall, why would you not set the truss/rafter directly on the wall?

I would put a gussett on to tie the new rafter to the old one(which should already be tied to the plate) if more is needed you can still run strapping up over the new rafter and down to the plate on both sides to tie it down.Never been a problem here but our codes aren't as stringent as some.If I understood the op correctly he was asking how it could be done without messing with the existing s&f That is why I mentioned not setting it on the wall(which obviously would be better)because that would involve cutting the old tails off,redoing the s&f and probably the top row of siding.

paulie · 08-12-2009, 08:46 PM

Thanks guy's for the input. Started the ball rolling today and should have pricing tomorrow. Think I will rest the load on a little knee wall on top of the top plate as described.

The more I get into using a scissor truss for this application the more I like it. Since the house is 36' wide it makes using a king post design difficult.

deep sliver · 08-12-2009, 09:01 PM

On something like this we would try to find an easier job to do. Don't get me wrong, this one we could do with flying colors and you could not tell we remodeled the roof when done, but,
we would make sure we were covered on this one very well. As I say there is easier money around. We usually find doing a first class job to an inexpensivly built home is always harder to do.

paulie · 08-12-2009, 09:12 PM

Quote:

Originally Posted by deep sliver

On something like this we would try to find an easier job to do. Don't get me wrong, this one we could do with flying colors and you could not tell we remodeled the roof when done, but,
we would make sure we were covered on this one very well. As I say there is easier money around. We usually find doing a first class job to an inexpensivly built home is always harder to do.

#1 Where are you from. Checked out your info, nothing.

#2 Established customer of mine. I agree it's a low end house but I don't have the clients knocking at my door that are multi millionaires.

#3 It's hard to turn down any work up here in MI. Would love to pick and choose like "you guys".

SC sawdaddy · 08-12-2009, 09:33 PM

That off set at the back window is going to be tricky. You'll have to put a header for your gable truss to sit on. Whats going to hold up the left side of the header?
Have you considered closing that area in to keep your soffit line straight?
Better get a temporary put up too, you'll have to raise the weather head.

WarnerConstInc. · 08-12-2009, 10:58 PM

Clip that back corner over window.

The quickest way would be to tear off the whole roof, set new trusses. Trusses are cheap. I would think around 50 bucks a pop, need 19.

Be a good guy and use 5/8 or 3/4 sheeting. Gonig to have a couple ass holes and elbows days but, that would be most efficient, to me.

paulie · 08-13-2009, 08:44 AM

[quote=WarnerConstInc.;745108]Clip that back corner over window.

The quickest way would be to tear off the whole roof, set new trusses. Trusses are cheap. I would think around 50 bucks a pop, need 19.

I have been working on that option also. But as posted earlier the people are going to remain living there. Girl is pregnant. Go figure.

Yeah, there's going to be alot of messing around on this one no matter what. Just got to make sure I cover my a**.

Joe Carola · 08-13-2009, 12:45 PM

[quote=paulie;745243]

Quote:

Originally Posted by WarnerConstInc.

Clip that back corner over window.

The quickest way would be to tear off the whole roof, set new trusses. Trusses are cheap. I would think around 50 bucks a pop, need 19.

I have been working on that option also. But as posted earlier the people are going to remain living there. Girl is pregnant. Go figure.

Yeah, there's going to be alot of messing around on this one no matter what. Just got to make sure I cover my a**.

The fastest and easiest way would be to cut off the existing overhangs and cut back the sheathing enough to expose the top plate and forget the scissor trusses and stick frame the thing and be done with it. Leave the existing roof on unless they want bigger attic space, then remove the existing roof.

I've done this type of job many, many times to create new roof lines. Code wise you will either have to cut sections of the plywood out for venting or you have to remove the existing roof shingles. You have to vent whether you remove the shingles or not. Good framing crew can have that roof framed in 1-2 days.

house bldr · 08-13-2009, 12:55 PM

I don't think tearing the trusses off would even be an option.You would lose all your ceilings inside,all attic insulation,all wiring in the attic would have to be unhooked and redone, it would be a MAJOR PITA!

Joe Carola · 08-13-2009, 01:29 PM

Quote:

Originally Posted by house bldr

I don't think tearing the trusses off would even be an option.You would lose all your ceilings inside,all attic insulation,all wiring in the attic would have to be unhooked and redone, it would be a MAJOR PITA!

The existing house are trusses?