How would you do this roof?

[MarkV]

MarkV

Nice looking setup there. I have given the rafters and collar ties some serious thought lately. You can even adjust them a bit higher from what I have read, anyway. Is your stained? Was that a spray on or brush on finish? If brush on, that would be a LOT of upkeep.

Yes I used a stain on our porch. We sprayed an oil base stain from an airless sprayer. As far as upkeep, I have never restained and the screen porch was first done 9 years ago. I do pressure wash once a year. This is a covered area which sounds like you are planning. I don't have a good photo but this may give you an idea of how it looks from the outside.

MarkV

 

[Johno Geo]

If you have Engineered trusses with no side walls, I trust you live in a mild climate.
If cost is a factor, and you will not insulate , I would fasten 2x4 perlins perpendicular to the top member of the trusses.
Then screw metal roofing to the perlins.
I just had a pole barn constructed in NW Indiana,
This seems like substantial construction for the intended purpose.
My purpose was an equipment storage building.

Johno Geo

 

[handirifle]

Ok I guess the onus is on us now. We'll decide on one of these designs, and when it gets going I will try to take pics and post the progress.

This WILL be painted underneath, so the std truss idea isn't a real big deal. I never planned on staining because the stain grade lumber will put this project way over budget.

 

[MarkV]

This WILL be painted underneath, so the std truss idea isn't a real big deal. I never planned on staining because the stain grade lumber will put this project way over budget.

Just so we are are on the same page. There is no stain grade lumber in what I did. It is a mix of standard framing lumber, pressure treated lumber and T-111 4x8' panels. I let it sit for a couple of months to let the PT lumber dry somewhat and sprayed it with an oil base stain. I did spray and brush it in, back brushing, to work it into the textured T-111.

MarkV

 

[dcyrilc]

handirifle,

The upper trusses on my barn are an 18 foot clear span. Singles on the ends and doubles on the center posts (one attached to each side of the posts). These are engineered trusses. The third pic shows the taller post in the center to provide the lateral support. I set my posts tall and trimmed them to length after the trusses were set.

 

[handirifle]

I see what you mean about the long posts but I have no idea how that could work on this setup. I understand about the lateral bracing, as well, since it is that way on my shop trusses.

I may have to go with a different truss design, one more like the semi cathederal ceiling. Has anyone here ever had the open truss design I am thinking of, and using X bracing? Not sure if that's the correct term, but thinking if a brace was run, say, from the bottom of the front truss, to the peak of the center truss, and vice versa. The same for the center to rear truss. Would that work?

 

[flusher]

How about an Japanese look--like this pergola I finished last month for my bonsai garden. It's a 10' x 10' Dutch hip roof with a Japanese-style ridge board. Not too difficult to build--I did it myself and I'm 68 years old.



You can add cedar shingles to make it a gazebo.
Add a roof and walls it becomes a Japanese tea house.

Have fun.

 

[LD1]

I see what you mean about the long posts but I have no idea how that could work on this setup. Just make your center post in the rear extend all the way to the peak of the truss.

I may have to go with a different truss design, one more like the semi cathederal ceiling. Has anyone here ever had the open truss design I am thinking of, and using X bracing? Not sure if that's the correct term, but thinking if a brace was run, say, from the bottom of the front truss, to the peak of the center truss, and vice versa. The same for the center to rear truss. Would that work?Yes. x-bracing will give the roof lateral support as well if you do it between all three trusses. (so you will have 2 x's.) but since you mentioned you wanted an open truss design, I did not mention bracing this way as it would just "clutter" your open design. Extending the rear post would solve this.

I'll see if I can find some pics to give you some ideas.

 

[LD1]

A google images search turned this up Google Image Result for http://www.jaragoskyconstruction.com/070120097.jpg

The appears to be what you are wanting. Or at least what I envision you are wanting only without the walls. As you can see, the center post extends all the way to the peak.

 

[Kays Supply]

The last post got me to thinking. We did a house years ago that had the truss system like he shows but they didn't use the cross member 2x4s. They put 2x4 tongue and groove across the trusses leaving the wood showing for a ceiling. They then put a buildup roof insulation on because it was for a house.That would give you the exposed look you descibed and might be strong enough for the load.

 

[jake98]

I must be missing something, how is that 'center truss horizontal rafter' method any better than a standard cathedral with a load bearing ridge?

 

[magicheater]

I must be missing something, how is that 'center truss horizontal rafter' method any better than a standard cathedral with a load bearing ridge?

Structurally probably not much difference. Cost wise maybe some difference. Aesthetics, maybe so. Adaptability for insulation, no walls so why plan for it. Availability of material, perhaps some merit. ease of construction...maybe.

 

[jake98]

I'm still scratching my head over it.. I can't come up with one reason why anybody'd frame it like that. Even if the point was to put the weight over the center posts, why run the rafters sideways? (assuming they could design a way to hang a structural ridge to a center truss, a center beam with a post to the ridge would do the same, but I'd think they'd just go the whole length with a bigger micro-lam ridge..)
I dunno..

 

[piller]

I like traditional timber frame structures, and they could work, but they are expensive and time consuming.
Do you plan for the spa to be centered in your 18x18 structure?
Do you want a truss over the center of the spa, or did you want it open?

 

[handirifle]

I'm still scratching my head over it.. I can't come up with one reason why anybody'd frame it like that. Even if the point was to put the weight over the center posts, why run the rafters sideways? (assuming they could design a way to hang a structural ridge to a center truss, a center beam with a post to the ridge would do the same, but I'd think they'd just go the whole length with a bigger micro-lam ridge..)
I dunno..

Jake
The only reason for the horizontal bracing is for support for the roof sheathing. I have measured the true distance between the posts and it will be 8'2" CTC. The spa pad is 18'x18', bot not the posts. With over 8ft between posts, and trusses, there is zero support for the sheathing.

The horizontal 2x4's will provide this, as well as a nailing surface.

As for a cathederal beam, there is no center post in the front, to place the load of the beam on. In the front, it is nearly an 18ft span.

dcyrilc

The long rear post is a great idea, but I see no way to make it work for me, am I missing something?The post bracket for the rear center post, is like the two rear corner post brackets, set in concrete. And they are all three on the same line. The center rear post, would bisect the rear truss.

I see the rear post in the attached link, but did they build the truss around it, or behind it? If my rear truss goes from post to post, then the rear beam can go no higher than the bottom of the truss. I am supposing, now, that I should have done all this BEFORE I had the pad poured, but too late now, so I have to work with what I have.

 

[dcyrilc]

dcyrilc

The long rear post is a great idea, but I see no way to make it work for me, am I missing something?The post bracket for the rear center post, is like the two rear corner post brackets, set in concrete. And they are all three on the same line. The center rear post, would bisect the rear truss.

I see the rear post in the attached link, but did they build the truss around it, or behind it? If my rear truss goes from post to post, then the rear beam can go no higher than the bottom of the truss. I am supposing, now, that I should have done all this BEFORE I had the pad poured, but too late now, so I have to work with what I have.

My posts are also inline. The outer truss nails to the outside of the posts (all three) and 2x6s are nailed vertically to the posts below them for additional support. The bottom of those 2x6s could be beveled to create a more finished look.

I think what I'm talking about shows in this pic.

 

[Cat_Driver]

Others have explained the traditional way to do the look.

Now a days you can do that look with foam beams and the smaller rib looking wood could be nothing more that 1/4" slices of 2"x4"'s. That if you just want the "look".

I was in a resort once and it was loaded with beautiful looking beams throughout the lobby, then one day it rained and the roof leaked and one of the "beams came down and it was nothing more that Styrofoam.

See them here:

Faux Wood Beams | The Look of Natural Wood for Less

 

[magicheater]

I'm still scratching my head over it.. I can't come up with one reason why anybody'd frame it like that. Even if the point was to put the weight over the center posts, why run the rafters sideways? (assuming they could design a way to hang a structural ridge to a center truss, a center beam with a post to the ridge would do the same, but I'd think they'd just go the whole length with a bigger micro-lam ridge..)I dunno..

Framing it like that provides nailers for metal roofing.

 

[handirifle]

OK I see how the rear post/trusses work. But doesn't that sort of negate the support of the beam, from below on the ends?

Let me ask this, from a different angle, would it be a bad idea, to set the rear truss directly over the two rear corner posts, and trim the top half of the rear center post to allow the truss to sit inline over the rear posts? In otherwords, instead of being a 6x6 (actually 5 1/2 x 5 1/2) to being 4 x 5 1/2, and the truss member would fill in the other 1 1/2". Nope, on second thought that won't work cause they're double trusses.

No, I can't see it working on my setup, unfortunately.

I will look into the "X" bracing a little more, that might be my best option.

The horizontal "rafters" are not for nailing a metal roof on, at least not for my application. here simply isn't anything to nail the sheathing to. Nailing the sheathing on 8' CTC would make a really bouncy roof. I could always do the standard rafter setup, but not sure I want a 2x6 underneath.

I will also look into the cost of tongue and groove boards, either 1" or 2" as opposed to sheathing.

 

[handirifle]

Cat driver
I have seen those, and didn't really like them.