Exclusive Building a detached deck

[PtldPlatypus]

Actually more like a rectangular gazebo (12x16). Planning on using concrete deck blocks and 4x4 posts every four feet. Wife wants joists and crossbeams to just be 2x4s to keep the deck surface close to the ground, but I'm not sure that's reasonable and/or wise.

With zero experience in framing a structure, I'd be interested in any tips any of y'all have for making this thing solid without costing me an arm and a leg.

 

[andalusian]

What are you going to use for the deck itself? I am a big fan of Cali bamboo and we used their products when we built our deck. Termites are a big problem here and heat can cause stuff to bend - our old deck had both these issues. As for height - we live on a hillside, but generally I think you want some space from the ground.

 

[PtldPlatypus]

What are you going to use for the deck itself? I am a big fan of Cali bamboo and we used their products when we built our deck. Termites are a big problem here and heat can cause stuff to bend - our old deck had both these issues. As for height - we live on a hillside, but generally I think you want some space from the ground.

Some space sure, but how much? I mean, if we're using 12" deck blocks, then 4" beams, then 4" joists, we're close to 20" off the ground already before a flooring surface is placed.

We're doing this on a budget and she wants to paint everything anyway ( ), so we're probably just using pressure-treated doug fir.

 

[UncleCliffy'sDaddy]

2X6 on the joists and cross beams. If you can afford Trex, go for it. If not, use a good quality stain. Paint is NOT a good way to go on a deck, especially in Oregon. Paint can get slippery (Stained decks can get slippery also but not like paint IMHO) and can also chip and peel. Stain holds up better. Be very, very choosy with your wood when buying it. Take the time to sort through it as you buy to make sure you’re not getting any crap wood (split, dog eared, etc, etc, etc). Just my thoughts from p[ast experience.....

 

[PtldPlatypus]

2X6 on the joists and cross beams. If you can afford Trex, go for it. If not, use a good quality stain. Paint is NOT a good way to go on a deck, especially in Oregon. Paint can get slippery (Stained decks can get slippery also but not like paint IMHO) and can also chip and peel. Stain holds up better. Be very, very choosy with your wood when buying it. Take the time to sort through it as you buy to make sure you’re not getting any crap wood (split, dog eared, etc, etc, etc). Just my thoughts from p[ast experience.....

We're actually going 3/4" plywood and outdoor carpet on the flooring surface. Also putting a roof on top of it.

See, I was thinking 2x6's for the floor supports as well. I fear I'm going to lose this battle though.

 

[julius]

Use torx screws. Never use Phillips screws or nails. Never.

 

[wizenheimer]

wow....a surprising lot of 'between-the-lines' questions pop up

structurally, 2 X 4 joists and crossbeams don't make sense. You can't span more than 3-4 feet with 2X4 and even then, you'll get deflection and bouncy action

* start with the profile...your wife wants it as low to the ground as possible. right? Well, that means your deck piers (concrete) need to be in holes so your beams need to be supported an inch or less above grade. A 12 X 16 deck? I'd use pressure treated 4X6 as the beams (all your structural wood should be pressure treated. If the beams span the 12' dimension, I'd space 4 of them evenly them at 0' - 5'4" - 10'8" - 16'0". Then run 2X6 joists supported by joist hangers. Depending on the type of becks surface you use, you might get away with joists running 24" on center. But if you're decking is some composite material you might be better using 16" on center spacing.

* anyway, with that you'd only be spanning about 5' with your joists. Considering that pressure treated is a little lower grade of lumber that span gives you a safety margin and a solid feel. As for the 4X6 beams, you could probably get away with just one row of intermediate piers, meaning you'd have to dig 12 holes.

* speaking of those holes: you will never be able to make the support plates of all 12 piers level with each other. Just won't happen. The solution, unfortunately, if you're doing it yourself, is to dig each hole 3-4 inches deeper, pick a control pier, cut a 4x4 post that may be 3-4 inches long, and level & string from there. It will be those midget posts that support your beams. And you'll want some type of hardware bracket to tie the posts and beams together. But don't do that until you have squared the entire deck framing

* which brings up another trick: plan on cantilevering your beams over those posts. In other words, your beams should cantilever at least a foot over the posts. That way, when the decks is done you won't be looking at a pier and the hole it's in. This will also reduce the span of the beams and make one intermediate row of piers adequate.

* speaking of those beams, for a 12' deck, they won't be 12' long. Theoretically, they should be about 11'8" long. That way you can have your end joists cover the ends of the beams. That would require a pair of 16' pt 2X6. Now, for appearance, those 2X6 as well as the ones on either end could be a standard 2X6 rather that pressure treated. PT can be kind of ugly. You can also dress up the face of the deck by attaching 1X6 cedar around the 4 sides.

* another trick: when you are ready to stat running your decking, pick a starting end and use a chalk-line or string to cut the beam ends straight and attach that outside 2X6. But do not cut the other end of the beams yet. Run your decking almost all the way to the end; then use the decking dimension to set the ends of the beams. That was you won't have to rip your final piece of decking

* use you bionic eye, but don't trust it too much. Keep checking that you are running the deck straight and even with a string line. And keep measuring either end and center of the installed decking to make sure you're square and even. Nothing like getting 2/3 of the way done and have 94" of installed decking on the left and 95" on the right. Unless of course you like trapezoids.

now, you mentioned a gazebo as part of the deck, but that introduces about a bazillion more variables. Then the first thing you have to do is build the support columns for the gazebo and in-fill the deck from there. And you'll need significant precision with those columns. And that will require more that standard deck piers, otherwise you could be looking at a collapsed gazebo after the first big wind...and yes, the wind can impact even a minimal structure

I don't mean for all that to be intimidating. It just takes plenty of planning. The work itself isn't too hard, although about 3 hours in your back be wishing the deck was 20" above the ground than 6"

 

[ABM]

2X6 on the joists and cross beams. If you can afford Trex, go for it...

Trex is really great stuff. It ain't cheap, but a great look and virtually maintenance free. If you're going to be there a number of years, worth considering.

 

[SlyPokerDog]

Actually more like a rectangular gazebo (12x16). Planning on using concrete deck blocks and 4x4 posts every four feet. Wife wants joists and crossbeams to just be 2x4s to keep the deck surface close to the ground, but I'm not sure that's reasonable and/or wise.

With zero experience in framing a structure, I'd be interested in any tips any of y'all have for making this thing solid without costing me an arm and a leg.

Need pics of the area.

 

[riverman]

Actually more like a rectangular gazebo (12x16). Planning on using concrete deck blocks and 4x4 posts every four feet. Wife wants joists and crossbeams to just be 2x4s to keep the deck surface close to the ground, but I'm not sure that's reasonable and/or wise.

With zero experience in framing a structure, I'd be interested in any tips any of y'all have for making this thing solid without costing me an arm and a leg.

use 2x6s for anything bearing weight 2x4s won't cut it for a deck..my 2cents and whatever you do...use deck screws and not nails!

 

[wizenheimer]

We're actually going 3/4" plywood and outdoor carpet on the flooring surface. Also putting a roof on top of it.

so, at least 200 square feet of roof, likely a bit more. You want the roof to overhang enough on all sides to mitigate your outdoor carpet getting wet. Don't use standard plywood either. Use pressure treated T&G or marine plywood

but you will build a sailboat if you use standard deck piers. You'll need much better anchors and IMO, you'll want 6X6 columns as roof support. 4x4 would wobble like crazy in any wind, even if anchored well.

have you considered paving stones instead of a deck? That way your 'patio/deck' would be at grade. And none of it will ever get dry rot. I'm betting overall there may not be a wildly significant difference between a framed deck and paving stones, and that's even assuming you get a paving stone contractor. And many of those contractors could include pouring concrete for your gazebo columns. There is almost no maintenance to paving stones. There will be maintenance for a deck

 

[SlyPokerDog]

have you considered paving stones instead of a deck? That way your 'patio/deck' would be at grade. And none of it will ever get dry rot. I'm betting overall there may not be a wildly significant difference between a framed deck and paving stones, and that's even assuming you get a paving stone contractor. And many of those contractors could include pouring concrete for your gazebo columns. There is almost no maintenance to paving stones. There will be maintenance for a deck

That's exactly why I asked for pictures of the area.

 

[HailBlazers]

@PtldPlatypus here's some inspiration on FB marketplace:

 

[PtldPlatypus]

so, at least 200 square feet of roof, likely a bit more. You want the roof to overhang enough on all sides to mitigate your outdoor carpet getting wet. Don't use standard plywood either. Use pressure treated T&G or marine plywood

but you will build a sailboat if you use standard deck piers. You'll need much better anchors and IMO, you'll want 6X6 columns as roof support. 4x4 would wobble like crazy in any wind, even if anchored well.

have you considered paving stones instead of a deck? That way your 'patio/deck' would be at grade. And none of it will ever get dry rot. I'm betting overall there may not be a wildly significant difference between a framed deck and paving stones, and that's even assuming you get a paving stone contractor. And many of those contractors could include pouring concrete for your gazebo columns. There is almost no maintenance to paving stones. There will be maintenance for a deck

Wife's pretty set on a wooden structure with a roof (and a small cupola) and rails. I've been concerned about stability with 4x4s as well, however she also wants sheets of T1-11 across the back side, so I'm hoping that should help with the wobble.

By the time I'm done, I feel like she's gonna ask for sheet rock...

 

[SlyPokerDog]

@PtldPlatypus here's some inspiration on FB marketplace:

That roof will be ripped off the 2nd big windstorm. The first will loosen things up, the 2nd will kill it.

 

[barfo]

Sounds like a lot of work, probably you should just get a divorce.

barfo

 

[wizenheimer]

Wife's pretty set on a wooden structure with a roof (and a small cupola) and rails. I've been concerned about stability with 4x4s as well, however she also wants sheets of T1-11 across the back side, so I'm hoping that should help with the wobble.

By the time I'm done, I feel like she's gonna ask for sheet rock...

ok, but that sounds like you're talking more about the gazebo than the deck...?

if you have decided on a deck like you describe...ok. But, I will say as a carpenter/re-modeler/contractor of 40 years, mostly in Oregon, what you're describing seems like you're asking for problems. It's too wet in Oregon for that kind of floor surface unless your roof extends far enough in all directions to keep the carpet dry. And you'd probably need at least a couple of full walls blocking the directions of prevailing weather so rain can't blow in. If you do build it like you describe, I'd recommend applying two layers of felt/tar-paper before installing the carpet, with the 2nd layer running perpendicular to the first. But then maybe you couldn't adhere the carpet to the felt

now, I understand if you are operating under a real tight budget....although I would think your S2 moderator's salary would allow you to have a luxury gazebo. But maybe you're paying for a Lamborghini right now.

as I said, considering your wife wants a low profile "deck", it sounds like a good situation for paving stones. I've actually built a couple of Gazebo's over paving stones. I don't have pictures with me here, but there are lots of examples on the net. They can be pretty handsome

something you need to consider...if you're sitting in your gazebo and you look up, you'll be looking at the framing and the underside of the roof sheathing. So build with that in mind. If what you have looks like cheap lumber and plywood with paint on it, you won't like staring at it for years

is this a do-it-all-yourself project?

 

[wizenheimer]

That roof will be ripped off the 2nd big windstorm. The first will loosen things up, the 2nd will kill it.

give me a break....as a dog, all you see are those posts

 

[Lanny]

Actually more like a rectangular gazebo (12x16). Planning on using concrete deck blocks and 4x4 posts every four feet. Wife wants joists and crossbeams to just be 2x4s to keep the deck surface close to the ground, but I'm not sure that's reasonable and/or wise.

With zero experience in framing a structure, I'd be interested in any tips any of y'all have for making this thing solid without costing me an arm and a leg.

Deck joists should be 2 by 6s. Decking either needs to be artificial or cedar. Everything needs to be fastened with corrosion resistant screws.
I had a new deck installed made out of T-Rex artificial material that won't fade or warp. The replaced a previous deck that used a lower grade artificial material that just didn't last. The supporting posts and joists were still good but just inferior decking. Came out beautiful although my wife changed her mind about the color but too late. I like the color. Kind of a dark brown.

Edit:
We also had a wrought iron rail installed because I have trouble with even the single step down to the patio. You can get those rails lighted if you want.

 

[stampedehero]

Trex is really great stuff. It ain't cheap, but a great look and virtually maintenance free. If you're going to be there a number of years, worth considering.

View attachment 32141 View attachment 32142

The railing is a good idea. You don't need railing if three or less step risers are in place. In NJ, we require railing four risers and more and guards if the deck is 30 inches high or more. The International Residential Code is what dictates what is acceptable. NJ has a more restrictive edition. I like the deck style!

use 2x6s for anything bearing weight 2x4s won't cut it for a deck..my 2cents and whatever you do...use deck screws and not nails!

Teko metal supports and Simpson Strong Ties recommend hot dipped galvanized nails as long as it's their product. The problem with screws is that the torque builds heat and can distort the screw. Additional live load weight further promulgates the distortion. Special products like Ledger Loks are made for decks that are attached to the house sill/studs. Nails made for deck joist hangers attached to ledger or side trimmers are acceptable. I would use metal supports and never rely on toe nailing or screws.

 

[stampedehero]

so, at least 200 square feet of roof, likely a bit more. You want the roof to overhang enough on all sides to mitigate your outdoor carpet getting wet. Don't use standard plywood either. Use pressure treated T&G or marine plywood

but you will build a sailboat if you use standard deck piers. You'll need much better anchors and IMO, you'll want 6X6 columns as roof support. 4x4 would wobble like crazy in any wind, even if anchored well.

have you considered paving stones instead of a deck? That way your 'patio/deck' would be at grade. And none of it will ever get dry rot. I'm betting overall there may not be a wildly significant difference between a framed deck and paving stones, and that's even assuming you get a paving stone contractor. And many of those contractors could include pouring concrete for your gazebo columns. There is almost no maintenance to paving stones. There will be maintenance for a deck

I like 6"x 6" column installation for multi story or large volume custom area decks. If a one story deck is planned, 4"x 4"posts cross braced with staggered mid span joist blocking is aok . The ledger attached to a house and column footings are vital.
Stand alone decks are good choices for a low height deck such as Plt's project.
Paving stones or patterned cement is a great idea for an on grade patio project. Plt's wife would then be attracted to an accessory foliage garden to match the effect. It keeps him working longer too.

 

[Orion Bailey]

2x6 on the cross beams for sure.

 

[PtldPlatypus]

ok, but that sounds like you're talking more about the gazebo than the deck...?

if you have decided on a deck like you describe...ok. But, I will say as a carpenter/re-modeler/contractor of 40 years, mostly in Oregon, what you're describing seems like you're asking for problems. It's too wet in Oregon for that kind of floor surface unless your roof extends far enough in all directions to keep the carpet dry. And you'd probably need at least a couple of full walls blocking the directions of prevailing weather so rain can't blow in. If you do build it like you describe, I'd recommend applying two layers of felt/tar-paper before installing the carpet, with the 2nd layer running perpendicular to the first. But then maybe you couldn't adhere the carpet to the felt

now, I understand if you are operating under a real tight budget....although I would think your S2 moderator's salary would allow you to have a luxury gazebo. But maybe you're paying for a Lamborghini right now.

as I said, considering your wife wants a low profile "deck", it sounds like a good situation for paving stones. I've actually built a couple of Gazebo's over paving stones. I don't have pictures with me here, but there are lots of examples on the net. They can be pretty handsome

something you need to consider...if you're sitting in your gazebo and you look up, you'll be looking at the framing and the underside of the roof sheathing. So build with that in mind. If what you have looks like cheap lumber and plywood with paint on it, you won't like staring at it for years

is this a do-it-all-yourself project?

Yes, very much a do-it-all-ourselves deal.

This has been very helpful. We had initially been thinking/talking about building this as one all inclusive piece (floors/posts/rolls/roof all interconnected, but I see there could be value in doing the deck surface and covering as two separate things. Definitely going to have the roof area hang close to two feet past the sides of the structure.

We're attempting to till and level the construction area today, and she's concerned about the possibility of ground settling beneath the pavers, so she's pretty set on the deck blocks. I think I'll be able to get her to see the light on 2x6s underneath.

 

[yankeesince59]

2X6 on the joists and cross beams. If you can afford Trex, go for it. If not, use a good quality stain. Paint is NOT a good way to go on a deck, especially in Oregon. Paint can get slippery (Stained decks can get slippery also but not like paint IMHO) and can also chip and peel. Stain holds up better. Be very, very choosy with your wood when buying it. Take the time to sort through it as you buy to make sure you’re not getting any crap wood (split, dog eared, etc, etc, etc). Just my thoughts from p[ast experience.....

This^^^...You can't beat Trex and Trex-like composites. I used it when I built a pool deck about 8 years ago and it looks just as good now as it did the day I built it...when I was shopping for wood and decking for my project I found some grey composite decking at Home Depot...yeah, it was more expensive but well worth it...no staining, no warping or cracking, no fading, not slippery at all even when wet, nearly indestructible and extremely good looking...I still get compliments on it.

 

[wizenheimer]

I like 6"x 6" column installation for multi story or large volume custom area decks. If a one story deck is planned, 4"x 4"posts cross braced with staggered mid span joist blocking is aok . The ledger attached to a house and column footings are vital.
Stand alone decks are good choices for a low height deck such as Plt's project.
Paving stones or patterned cement is a great idea for an on grade patio project. Plt's wife would then be attracted to an accessory foliage garden to match the effect. It keeps him working longer too.

sure, 4x4 works for the deck itself, although I'd recommend 6x6 if the height exceeds 8'. And you're right about the joist blocking. In the case of the 12x16 deck platypus is talking about, assuming the joists run in the 12' direction and one mid-span beam, a row of blocks directly on that beam would lock that fram up solidly

But I was talking about 6x6 for the gazebo columns. Any time a substantial roof is involved, and I'd consider 200 square feet substantial, I want to have 6x6. It's the column cross-section area that resists wobble, racking, twisting, & bending. A 4x4 has a cross-section of 12.25 sq.in. A 6x6 has one of 30.25. And you can even order an actual 6x6 that has a cross-section of 36 sq. inches.

and you shouldn't use piers with post stirrups either. Those offer no resistance to any kind of horizontal shear more than 4' above the stirrup

I've built several free-standing and attached roofs for decks and patios. After the early days of seeing how poorly 4x4 performed, I always advised 6x6. And I advised them being embedded in the pier. Generally, that would be a 16-20 inch sonna tube concrete form, and the post embedded 18-20 inches. You do that and the roof will be solid.

of course, if money is no object, you can use steel with a baked enamel paint cover. I was sub-contracting finish carpentry on a 2 million dollar home one time. IIRC, it was about 11,000 square feet. Anyway, they built a 24x36 foot gazebo a little ways from the 'main' house. It was a contractor from Eugene who built it. They had steel columns resting on concrete columns that were 3 feet above grade. Spaced 12 feet apart. The roof-beam stirrups were designed for 6x12 number 1 doug fir imported from Canada. There was no blemish on those things. Full hip roof on top with, again, #1 doug fir rafters, Perlins, and blocks. And all of the lumber was kiln dried. Then, believe or not, the owner had them install a copper roof. All the lumber was stained and sealed. And the deck/patio was some kind of expensive paving stone, that had 3' high walls of expensive blocks around some of the walls (remember those concrete piers the posts were on. And of course, there was electric, water, and gas supplied to the gazebo, in part for the bbq kitchen they had out there

yeah, kind of insane, but the owner was rich (owned a surgical group and commercial real estate). I got to know him a little so I asked him how much it cost. He said it was up to 174K and that was before the copper roof. Funy thing was there was a 6' paving stone walkway that just terminated out in the yard a ways from the gazebo. I asked about that and he said that was headed to the pool and pool house, plus tennis court they planned on doing the following summer. yeeeeeesh

 

[wizenheimer]

Yes, very much a do-it-all-ourselves deal.

This has been very helpful. We had initially been thinking/talking about building this as one all inclusive piece (floors/posts/rolls/roof all interconnected, but I see there could be value in doing the deck surface and covering as two separate things. Definitely going to have the roof area hang close to two feet past the sides of the structure.

We're attempting to till and level the construction area today, and she's concerned about the possibility of ground settling beneath the pavers, so she's pretty set on the deck blocks. I think I'll be able to get her to see the light on 2x6s underneath.

if you're doing it yourself, then paving stones probably aren't an option. Those are labor-intensive. There would be no settling problems though because you dig out to the undisturbed soil, then add 6" of gravel, then compact the hell out of that gravel. Then add sand for the bed of the paving stones. And you need a big stone/saw.

 

[andalusian]

This^^^...You can't beat Trex and Trex-like composites. I used it when I built a pool deck about 8 years ago and it looks just as good now as it did the day I built it...when I was shopping for wood and decking for my project I found some grey composite decking at Home Depot...yeah, it was more expensive but well worth it...no staining, no warping or cracking, no fading, not slippery at all even when wet, nearly indestructible and extremely good looking...I still get compliments on it.

The only problem with Trex is that it is clear that it is not wood - which really bothered my wife and why we went for the Cali Bamboo option - all the advantages of composite with a more organic look. IIRC, the difference in price at the time was not too huge - but obviously it was more expensive than the mass produced stuff from the big box stores.

 

[PtldPlatypus]

sure, 4x4 works for the deck itself, although I'd recommend 6x6 if the height exceeds 8'. And you're right about the joist blocking. In the case of the 12x16 deck platypus is talking about, assuming the joists run in the 12' direction and one mid-span beam, a row of blocks directly on that beam would lock that fram up solidly

But I was talking about 6x6 for the gazebo columns. Any time a substantial roof is involved, and I'd consider 200 square feet substantial, I want to have 6x6. It's the column cross-section area that resists wobble, racking, twisting, & bending. A 4x4 has a cross-section of 12.25 sq.in. A 6x6 has one of 30.25. And you can even order an actual 6x6 that has a cross-section of 36 sq. inches.

So let's say that I'm only planning on spacing my posts 4' apart, both on the 12' and the 16' sides--so I'd basically have 14 posts around the perimeter of this thing, in addition to 6 more underneath the floor. Would 4x4s still be insufficient in that scenario; do I still need 6x6s at least at the corners?

 

[wizenheimer]

So let's say that I'm only planning on spacing my posts 4' apart, both on the 12' and the 16' sides--so I'd basically have 14 posts around the perimeter of this thing, in addition to 6 more underneath the floor. Would 4x4s still be insufficient in that scenario; do I still need 6x6s at least at the corners?

I'd say that depends of the weight of your roof

in that case I'd recommend x-bracing on all sides that don't have t-1-11. Not for every space, but on every corner, both directions. When I think about it if you're going 4' O.C. with your 4x4's, maybe a type of V-bracing would work, but that always looks incomplete

this is one way, although I've used a modified version before. The best angle is 45 degrees although I suppose you could go down to 30 degrees and still have an impact. I'd want to go from the deck all the way up and tie into your beams. But yeah, that's going to look pretty industrial and you probably couldn't get approval from your war department

it's prettier to do something like this (imagine a roof instead of a deck):

but to clean it up you'd use this modification:

notice how the brace is the same dimension as the post & beam. That would mean you'd use 4X4 braces, cut on 45 degrees and then lag bolt the braces to posts and beams. That takes some time to get clean cuts and to cut/drill mortises for the lags to rest on, but it looks the best

also notice the blocking in between each rafter. You should put blocking on top of each beam in your deck, and on top of each beam in your roof. You should also use some type of Simpson hurricane clip to tie each rafter to your beam. They are easy to install (after blocking), and there's the bonus that at least once you'll hammer your thumb (when you do, remember what Mark Twain said: "profanity offers a comfort not available in prayer")

by the way, I don't think adding an extra post to each side is going to do much for wobble. I probably wouldn't bother

I don't know what type of roof you're planning on. There are shed roofs, gable roofs, hip roofs, etc. Now, a shed roof is easiest to frame

but you'll notice that one end is taller than the other. So, you could have 8' posts on one end and 11' posts on the other...welcome to wobble city. Now, you mentioned T-1-11 on one end so if you had that sheath on the tall end you'd mitigate that problem

if you're going to use composition shingles, the minimum slope is 2/12. That's 2 inches of rise for every 12 inches of run. So, for a 12' roof, if your low-side posts were 8', your high side posts would be 10'.

you can also consider a metal roof with a baked enamel finish. Comes in lots of colors, is much lighter than comp, is much easier to install, and can be applied to less of a slope than 2/12. Plan on bleeding though. I always do whenever I work with metal. Now, if you go that route it's important your finish roof dimension matches the width increment of your metal roofing. 1 foot roof panels can be attractive and easy to install. But that means you want your roof frame to be 14' or 15' or 16', not 14'5"

a gable roof is a little more complicated:

notice that there is a ridge rafter that runs the length of the roof. You'll want one of those. And it should be 0ne dimension larger than your rafters. In other words, if you're using 2x6 rafters, the ridge should be 2x8. Which brings up what you support that ridge rafter on. I'd recommend running your roof beams on all 4 sides. If the 16' run is your bearing beams for the rafters, than you'd use inside 4X hangers to install the two 12' beams (11'5"). Two advantages to that (and I'd install them in the shed roof too). One is that you can support the ridge rafter with a short stud on top of the beam. The other is this allows you options to add bracing to mitigate wobble, if it's too much when you get to that point

also, notice the collar ties/ceiling joists in that frame. You should put at least one at the mid point

if your wife wants a hip roof, you should probably just shoot yourself

 

[PtldPlatypus]

I'd say that depends of the weight of your roof

in that case I'd recommend x-bracing on all sides that don't have t-1-11. Not for every space, but on every corner, both directions. When I think about it if you're going 4' O.C. with your 4x4's, maybe a type of V-bracing would work, but that always looks incomplete

this is one way, although I've used a modified version before. The best angle is 45 degrees although I suppose you could go down to 30 degrees and still have an impact. I'd want to go from the deck all the way up and tie into your beams. But yeah, that's going to look pretty industrial and you probably couldn't get approval from your war department

it's prettier to do something like this (imagine a roof instead of a deck):

but to clean it up you'd use this modification:

notice how the brace is the same dimension as the post & beam. That would mean you'd use 4X4 braces, cut on 45 degrees and then lag bolt the braces to posts and beams. That takes some time to get clean cuts and to cut/drill mortises for the lags to rest on, but it looks the best

also notice the blocking in between each rafter. You should put blocking on top of each beam in your deck, and on top of each beam in your roof. You should also use some type of Simpson hurricane clip to tie each rafter to your beam. They are easy to install (after blocking), and there's the bonus that at least once you'll hammer your thumb (when you do, remember what Mark Twain said: "profanity offers a comfort not available in prayer")

by the way, I don't think adding an extra post to each side is going to do much for wobble. I probably wouldn't bother

I don't know what type of roof you're planning on. There are shed roofs, gable roofs, hip roofs, etc. Now, a shed roof is easiest to frame

but you'll notice that one end is taller than the other. So, you could have 8' posts on one end and 11' posts on the other...welcome to wobble city. Now, you mentioned T-1-11 on one end so if you had that sheath on the tall end you'd mitigate that problem

if you're going to use composition shingles, the minimum slope is 2/12. That's 2 inches of rise for every 12 inches of run. So, for a 12' roof, if your low-side posts were 8', your high side posts would be 10'.

you can also consider a metal roof with a baked enamel finish. Comes in lots of colors, is much lighter than comp, is much easier to install, and can be applied to less of a slope than 2/12. Plan on bleeding though. I always do whenever I work with metal. Now, if you go that route it's important your finish roof dimension matches the width increment of your metal roofing. 1 foot roof panels can be attractive and easy to install. But that means you want your roof frame to be 14' or 15' or 16', not 14'5"

a gable roof is a little more complicated:

notice that there is a ridge rafter that runs the length of the roof. You'll want one of those. And it should be 0ne dimension larger than your rafters. In other words, if you're using 2x6 rafters, the ridge should be 2x8. Which brings up what you support that ridge rafter on. I'd recommend running your roof beams on all 4 sides. If the 16' run is your bearing beams for the rafters, than you'd use inside 4X hangers to install the two 12' beams (11'5"). Two advantages to that (and I'd install them in the shed roof too). One is that you can support the ridge rafter with a short stud on top of the beam. The other is this allows you options to add bracing to mitigate wobble, if it's too much when you get to that point

also, notice the collar ties/ceiling joists in that frame. You should put at least one at the mid point

if your wife wants a hip roof, you should probably just shoot yourself

Gable roof is the plan. This is awesome. And we've been talking about the angled cross braces like you recommend, so I'm glad to see that you say they'll be helpful.

I'm also grateful that my wife has now decided we're going to take down all our arbor vitae before we start building. Gives me time to digest all of this information.