I’m not sure if I’m in the right section but here goes. I am building a pretty standard gable roof 12×16 shed. I am now to the trusses. I am building them with 2 – 2×4’s and have cut all of the gussets. I plan to do a birdsmouth and tie the ends in with hurricane ties. My question is: I think I messed up and cut the gussets out of 1/2″ plywood. Should that have been 3/4″ plywood? I am nailing the gussets on both sides at the top each truss. I am very new to this and trying my best to learn so be gentle.
Discussion Forum
Get It All!
UNLIMITED Membership is like taking a master class in woodworking for less than $10 a month.
Start Your Free TrialCategories
Discussion Forum
Digital Plans Library
Member exclusive! – Plans for everyone – from beginners to experts – right at your fingertips.
Highlights
-
Shape Your Skills
when you sign up for our emails
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. -
Shop Talk Live Podcast -
Our favorite articles and videos -
E-Learning Courses from Fine Woodworking
-
-
Replies
the trusses you are building do not need a birds mouth cut. just toe nail the trusses on the bottom cord to the top of the walls and you should be good to go. the 1/2 plywood you are using for gussets are plenty strong. you do not need to use 3/4 plywood for the gussets, that is unless you have the 3/4 and not the 1/2 plywood. either one is plenty strong! do not forget the plywood gussets at the intersection of the bottom cord and the rafter(top cord) use some wood glue and nails on all of your gussets. I hope this helps you out.
I appreciate your reply. I do not have bottom cord just the 2 - 2'x4's and gusset. I have attached a couple of pictures to illustrate. With that being known do you think it would still be structurally sound?
6205589's advice is good, but you might be better served at Fine Homebuilding. There's a link at the bottom of this page on the far right.
Good luck!!
I apologize as I didn't see your reply until after I replied. I will post in the other forum in the future. Thank you.
Structurally speaking, those big gussets don’t do much for you. The fastening of the 2 X 4 to a chord or, since you don’t have one , to the top of the walls will be keeping them from caving in under load. I assume there are no snow loads where you live hence this design, up here in the great white north there would be a bunch of cross members and 2 X 6 trusses.
There better not be any roof load! The walls are not likely adequate to keep the trusses from sagging and the walls spreading. Only the end walls will do that, or chords across from one top plate to the other. As designed right now, the 2x4 truss members can bend at the bottom edge of the plywood gussets, pushing out the walls. Not a good thing.
To call that a truss is a misnomer and I have serious concerns that it could handle any kind of roof load at all. You say you don't have the bottom cord does that mean you intend to add one? As pictured what you seem to have is more of a rafter system without the ridge beam not a truss, but rafters are usually at least a 2x6. Your mention of a birds mouth makes me question whether you are aware of the difference between rafters and trusses. Either way I have serious concerns about it's ability to withstand any amount of wind or snow load.
Agree with the above.
The thickness of the ply is not that relevant here.
It would be fine though if there are rafters added to prevent spreading under load. For such a small shed you probably only need one or two, but it makes sense to add one per truss.
Rob to clear up some potential confusion with terms. Here in NA rafters are the boards forming the pitch of the roof and are usually 2 x 6s or 2 x 8s depending upon anticipated load. Joists would be used to tie the walls together usually 2x6's since live loads are usually mimimal in attics. What the OP seems to be building is the unwanted love child between a truss and rafter system and at least IMO it looks woefully inadequate.
:-) Uk experience - Joists are for the floor, rafter was the common term for the joists in the ceiling. Joists is of course, as you say the correct term.
You have essentially a cord on the gable ends. Of course having plate to plate cross members would be a good thing but I'm guessing you want the space open for your own reason. Gluing the gussets is good advise. A metal truss plate at the peak would be helpful but the gussets should be adequately nailed in any case.. A birdsmouth (+ or) a metal truss to top plate tie should be adequate to prevent the walls from pushing out considering that you also have the roof sheathing. I would use t&g plywood for the sheathing. If I was concerned I'd construction adhesive the sheathing to the rafters and also glue the tongue. Nail at 6" centers or less. It's not much of a span, it's not going anywhere. It's a shed!
I built a shed from online plans last year, it took a lot of the guesswork out of the built and saved time. https://myoutdoorplans.com/shed/12x16-shed-plans/#google_vignette
Built a Norm Abrahms New Yankee Workshop 8x10 shed 15 years ago.
2x6 rafters but no bottom chord or joists at all. Birds mouth at top of walls, and a 2x12 down the length of the peak that the 2x6 rafters were nailed to.
Just south of the NH border so gets plenty of snow. Never an issue and the walls aren’t spreading apart. Roof slopes at 45 degrees.
But agree 2x4 rafters are not enough.
Mike
I will only add an 8 x 10 shed is a lot different than a 12 x 16 one. Sixteen feet of wall without some sort of cords or joists will fail in my opinion. Your side walls are no more than 5 feet from an end wall his are twice that.
About 20 years ago I built a shed to get stuff out of the garage so I could use it as my shop. It was over-built compared to shed "kits" and plans I found at the time but it's still standing. I made trusses from 2x4's with 1/4 in. plywood gussets glued and nailed. The chord sits on the top plates on the wall. No birdsmouths required.
At the time a local lumberyard was offering a similarly sized shed that they would deliver. Due to the height of the shed on their truck they told me special permits were required to haul it. With that in mind and thinking my shed might need to be moved one day, I attached the trusses to the top plates with lag screws from below. The sheathing is split on the ends at the join between the end wall top plate and the chord. The roof could be removed by separating the vinyl siding on the ends and removing the lag screws. The over-engineering gene I got from my dad was working overtime. :)
A truss is an engineered design that accounts for all the load factors of the roof and ceiling.You need a ridge with that design or your rafters will sag and spread the walls
Whose design are you referring to?
While a ridge board is traditionally used with rafters it does not by itself keep the rafters from sagging or the walls from spreading. He also would need gable wall studs and some type of ceiling joist or chord on the rafters. Regardless I think the OP has long ago abandoned this post.
I really appreciate all of the replies here as it has made me realize that my original design was really flawed. The guide I was going by for the most part was King's Fine Woodworking on youtube. I think his was a 10'x16' so I was thinking that I could apply the same general principals to my 12'x16' shed. I went by the material list from another person that is for a 12'x16' shed. I think now I will go by the truss system that they are showing. My question with going by theirs is are they using gussets on both sides or only 1. I will attached the new one I am referring to. Once again I appreciate all of the replies as I had no idea it would garner so much attention but has helped me out a lot.
I can't tell what they did. I put gusset plates on both sides of all of my truses except the end ones. Their outside faces were sheathed, though, so like one big gusset plate.
What I was confused about is how the youtube video I was going by was able to get away with not using a lower cord or king post. They simply used a birdsmouth cut and a 3/4" gusset on both sides on top. I have attached a print screen of what I'm talking about.
You can do anything on YouTube. ;)
Do they later end up tying the tops of the walls together? Where are they located? Maybe no snow load to contend with? How long ago did they build the shed? Did they have to go back later and fix it?
I'd be inclined to do a little research on truss design. Maybe contact a local company that makes trusses to get a quote for trusses for your shed. They'd probably provide you with a drawing of what they'd supply. And who knows, might be more cost effective to have them supply properly engineered trusses.
I'm not 100% for sure of the background other than the guy used to own a construction company and seemed to know his stuff but who knows. It was the most thorough and comprehensive video I came across while searching diy videos for sheds. He is in Colorado so I assumed it was being build with snow load in mind. I am in Texas and we get no snow. It is a highly rated 5 series video that seems very enticing due to the attention of detail and claims of "going by code". Again it is the internet and youtube so take all of that with a grain of salt. I would assume that other than praise in the comments you would get people saying how it was wholly underbuilt and the like if that was so. That could just be a bunch of beginners praising due to looks and approach to detail like myself. I will probably just go with truss design that I referenced above with the king stud and lower cord design. Are we all in agreement that that design would be sufficient?
I know a lot of guys who "used" to own construction companies, usually there's a reason they don't own them anymore.
I'm somewhat familiar with King and his videos having watched a few, not the worst I've seen but certainly not someone I would follow blindly. His wood working skills seem like he developed them as a carpenter and his projects at least the ones I've seen all have that carpenterish feel to them. My skin crawls when he smears glue with his hand and jokes about it.
As for his design and being to "code" I know it would not pass code where I live but codes in rural areas can be a lot more loose than they are here.
You may not get snow in Texas, but I venture a guess you can get some pretty good wind which puts its own kind of stress on a roof and structure. Over building is always better than the inverse.
I'm told my ex has a lot of likes on facebook, I don't dabble there so I don't know if that means much, however I have actual experience to the contrary. I would not let online "stars ratings" or "view counts" guide any build advice for your shed if you intend to stand inside it.
Ok thanks bud.
Looking at 11:30 min in the video, one can see them building a heafty box structure around the edge of the roof with a 2 X 6 inches fascia, a 2 X 4 along the wall and a structural soffit. This is an unusual design but may well compensate for the lack of cross members by keeping the walls from spreading appart under load. https://m.youtube.com/watch?v=y-rbgn0Xv3Q
In case anyone was curious about my progress. I have attached a truss that I decided on. It's not the best pic but there it is. Hopefully it keeps the roof on.
You need a collar tie or ceiling joinst when doing rafters to keep the walls from wanting to spread. Especially true if there is a snow load.
If you moved have moved it up a bit for more height it would be called a collar tie.
I am going by the attached pdf instructions here. If you are bored you can check out page 12. That is what I am going off of.
Since you are using a 2x4 lumber size, it can easily cover up to 90 feet distance with no longer than 9’ section of the ceiling unsupported. For the gussets, you can use the 1/2" plywood without much concern. Make sure you choose the right plywood as OSB, particleboard, or MDF won’t be good.
This forum post is now archived. Commenting has been disabled