Building a patio cover with exposed beam framing, need some advice
 

I'm in the process of building a gable roof over my patio. My plan is a 5/12 pitch with exposed 4x6 rafters placed about 22 oc because it lays out best that way. Rafter length is about 14 feet.

I need LVL's for the load bearing sides and I want that exposed. The load bearing sides are about 15' long with one side having a center support and the other being an unsupported span of 15'. My thought was a double 1-3/4 x 11.75" LVL on the unsupported side with a spacer and a 2x12 to make 5.5" which is my post size. On the side with a center support I'd go single 1-3/4 x 11.75 and build a spacer wall to fill the full 5.5". Across the front gable end, the span is 23' with a center support. My plan is a single LVL 1-3/4 x 11.75".

My problem is, as I said above, I want the beams to be exposed and I can't seem to find anyone that carries a treated LVL. I'm also debating if I want my 4x6's to be treated even though they'll have 1" stained tongue and groove carsiding on top of the exposed rafters and then on top of that 2x4's to attach metal roofing. the Space between the metal roofing and the carsiding will also act as my wire chase for lights and a fan.

Okay builders, LMK what to do! I'll post a pic of the project later.

Hi Nick, Of course I've no knowledge of the regulations... But as far as the unsupported span goes you can use those timbers with some flat steel in between. We call it a flitch beam and this may be the answer for you. Do a google of flitch beams for more info. Good luck.

Thanks Bill! I've got a guy working on calculating the header beam to make sure that my plan will work. My biggest concern is maintaining the look I want. I decided to just use 4x6 Douglas Fir for the rafter beams rather than treated and I'll stain and seal them in a darker color than the ceiling carsiding to make the ceiling really stand out. I wanted to avoid wrapping the header beams but I think there are some stainable products out there I can wrap them with and give them the same darker tone as the rafters.

Pic of the project at hand. I paid a company to do the stamped concrete then I laid the 600+ Belgian tumbled blocks for the seating walls and columns. There's a lotta adhesive in them thar walls. To the right where the table and chairs are, I'm building a pergola or buying one of the aluminum pergolas with louvers that can be opened and closed. Those things cost a few bucks so I'm leaning towards doing something with lumber in the same color as the rafters and headers to tie everything together.

http://forums.pelicanparts.com/uploa...1757544394.jpg

I think Pacific Woodtech has a weatherproof LVL, could possibly use Glulam beam. They will be covered under the roof? Check what your required snow load is. If I understood correctly you want to span 14' with a 4x6 that sounds way too small to me but your codes are different.

http://forums.pelicanparts.com/uploa...1757547739.jpg
http://forums.pelicanparts.com/uploa...1757547739.jpg
I through bolted 5- 2x6s together to make beams that support doubled up 2x6 for rafters for this exposed 12'x12' pergola. I think a 5½" tall beam looks more to scale for the size of the structure as opposed to 11½". It proved itself strong enough the first winter with 5' of snow on top.

Solid lumber would be my choice if they are exposed to the element but I much prefer Gluelam for a much better look then LVL. All engineering lumber is more stable compare to lumber. If they go under a roof, gluelam is the way to go. Stains nicely especially dark color and being way up there. I suggest coat it with flat (for the natural look )or semi gloss poly. Paint the exterior tails to keep from the element if its under a eave. They do cost more compared to lumber.

Look at rafter table to get the correct timber size or call your local lumber yard, not HOme Depot since those guys have no clue, and they will have the correct size for you. My kids and I built our second story deck using treated 4x8, 18' span, 12" center. I wanted to eliminate bounce. Painted the underside for protection.

slightly unrelated,

How 'tall' would you want the pergola to be?

Most of the metal pergola mfrs only do 8'

I did find one that 10' which was right about what I needed to clear my windows.

So . . if you need it tall you might be out of luck anyway with the metal prefab things.

I built mine 10' tall just for esthetics. It just feels and looks better when it's up high. Laminating multiple full size lumber guarentees no grain split and failure. And bolt lam eliminates glue failure. I milled my own lumber at 2x6 and through bolted for this reason. I milled the posts 6x6. If they split no big deal.
I finished with marine once and done sealer, nothing more. Applied with a bug sprayer

The bottom of my header beam will be at 102". The Luxury Pergola co makes a 9' model if I choose to go the aluminum route. I can cut the posts down to make the top whatever height works for my application.

I found Pacific Woodtech when searching treated LVL's. I was hoping to find someone local. I called a local yard yesterday. They are going to get me a price on treated LVL and then price LVL with a stainable wrap to conceal the LVL.

I checked snow load and used a span calculator. At 24" OC a 4x6 DF is rated at a max span of 16'11" for a 20lb snow load. I'll be at 22oc so good to go there! Thanks for the suggestion.

https://plib.org/resources/calculators/max-span/

I'm not a fan of gluelam beams I'd rather wrap them than have the appearance of a bunch of 2x4's stacked together.

I am quite interested in this thread .... thought I had a small project scheduled at my parents ... mebbe not now :(.

Type slower Nick ;)

UGH! This all started out with my wife wanting a new fence to replace our old vinyl fence. Once I decided on the style of fence I realized if I finish installing it, I'd have to bring in small equipment for the patio work and it would be difficult to get concrete into the area so I decided to do the patio which then snowballed into framing the roof over the patio. And once I'm done with all this nonsense, I have to finish the fence! It has been a pretty big project that has consumed a lot of my summer since I've done all of it so far by myself. My son did help a bit since I went over to his house and helped him install a new privacy fence.

I told one of my friends I don't have to work a regular job because I'm saving so much money doing all the work myself! You know, rather than paying someone 60K to do all this, It's only costing me 30K so it's like I just made 30K :D I think that's called "fuzzy math"

BTW, if you're going to tackle something like what I'm doing, I'll post some pics of what I'm doing. I'm tying the header beams into the house but I'm not using hangers or a post down the wall. I'm opening the wall cavity and adding support for the beam to rest on.

A good friend is going to help me set the rafters. He suggested tagging 2x6 or 2x8's together as rafters and then wrapping to achieve the look I'm going for. I thought about it but I like the look of a single thick piece of lumber. Plus, I told him then I have to spend time wrapping the rafters and I'm running out of time to complete this project. I only have about six or seven more weeks to get this nonsense done before the weather gets to where I'm not gonna want to work in it.

My rafters are 15" on center which provides a 12" bay. What are you going to do for a lid? I used corrugated tinted polycarbonate. The space is illuminated but not too hot at noon. Stronger than wood, never rots, fast and easy install. My slope drop is 3" in 12'. It looks like a flat roof but sheds water perfectly. That's ¼" drop per foot, the minimum to avoid ponding water. Nice well illuminated space

Luxury Pergola is the one I built. last year they had 10' but seems they only offer 9' now. I'm a little sore cause they abandonded the way they put them together about 3 months after I got mine done and went with an entirely new setup that isn't compatible. They are really nice and sturdy though.

For the pergola I plan to do a wood slat ceiling if I don't go with the aluminum adjustable slat model. The aluminum one appeals to me because I can close the roof if it's raining and people can still sit outside. And I can adjust the louvers based on the sun to provide shade. I'm just not fond of the price tag. I wish Luxury Pergola offered a manual open/close roof rather than a motorized only. I figure the roof will be open most of the time so why have a motor to do what I can do manually on the rare occasion that I'd close it?

I used rough cedar beams on mine. Stained, no need for treated lumber. No visible fasteners. Installed bead board plywood as the first of the roofing plies, to simulate bead board from underneath. That was painted a light color.

If you use dimensional or engineered lumber, it can be wrapped and made to look like one-piece beams. Not hard, just takes care and time.

You'll be very surprised how nice it is to have that roof closed.

It's a very rare occasion I have mine actually open full vertical.

like right now for example!

http://forums.pelicanparts.com/uploa...1757621797.jpg

My local lumber yard supplied us with PT LVLs when we did a pedestrian bridge. They usually have access to the mfg engineers and can calculate the spans & sizes.

I used an old barn beam (untreated) on my porch roof. Not a problem as it never gets wet, but once in a while we get a boring insect(see/wasp) that likes to make holes.

If you look at that pic I posted, you'll see a tree on the left (East) and the branches of another on the right. Shade isn't a problem but rain... yeah that's when it'll most likely be closed. That motor system, from what I can figure, adds about $2000 to the price of the thing and I just don't see using it that often. Plus my concern is that it becomes a potential source of problems in the future. My primary reason for wanting the pergola with adjustable louvers is just in case we have a large gathering and everyone couldn't fit under the 23x14 roof area. The pergola will add another 18x12 of covered area if I go with the aluminum one.