How can I prevent a sagging soffit style ceiling when using soffit material for the installation?
Asked by Kiieslav Onishchuk 
4 months ago
Last Updated: June 5, 2024
I’m trying to create a soffit-style ceiling using soffit material. Any tips on how to prevent it from sagging?
A few pop rivets at the connections could be beneficial.
Consider applying subfloor glue along the seam. It could be beneficial, although I haven’t personally tried it for this type of project.
Tim, don’t glue these seams together.
You’ll want something sturdier than those OSB strips. Opt for 1x4s for a more secure nailing surface, and place them 16″ apart.
Double up on every 16″ and attach securely.
Place 2x lumber every 16 inches and opt for roofing nails over staples. Staples are likely to come loose when the OSB expands due to heat and moisture. Remember to leave a small gap behind the head of the roofing nails to accommodate the expansion and contraction of the vinyl without causing wrinkles.
I believe you may be running it the wrong way. I have had no issues with an 8 foot span on mine.
Hey Geneva! Just wanted to let you know that this is actually a 20-foot span. I tried putting the 2 pieces together but it’s not going too well.
The length of mine is 15 and the width is 8 so no need for a connection. How wide is yours?
Hey, you should go in the opposite direction
Hey, my outdoor patio space measures 20’x20’
Hey , I think I’ll encounter a similar problem but in the opposite direction
Hey , remember not to butt them together… it’s better to overlap them
Hey , I’ve noticed that if you go in the opposite direction, you can secure a screw in each truss/joist/rafter, or whatever you prefer to call it, and it will only sag about 2 feet. At least that’s what I’m seeing.
That’s the correct answer.
How many inches should the overlap be?
Typically, the panels come with a factory overlap.
Hey , approximately 1 to 1 1/2 inches.
Hey , I’ll check and see if these work.
Hey , you can trim a bit off the nail strip and attach it to overlap.
The problem is that the other end of the soffit material is not properly attached because it’s hanging upside down, which is causing the material to sag.
Increase the number of hosts to one every 16 inches and secure them with white screws.
Make sure to run the pieces in the opposite direction of the rafters for better support.
Get rid of the osb. Install treated 2 x 1 counter battens every 16″, securing them at each joist with 4.0 x 50mm screws. Use color-matched (or black or white) polytop nails (25mm to 1-1/4″), and hammer them in with a nylon hammer – 3 nails per width at every counter batten.
It seems like the bottom piece is nailed too tightly. Try loosening the bottom one and tightening the top one. Avoid nailing them tightly, riveting the sheets together, or gluing anything in place. Consider using 1x4s with 16-24″ spacing instead of OSB. And remember, don’t nail it too tight as it needs to accommodate weather changes.
Bring your strapping closer together. I wouldn’t recommend using 1/2″ osb for strapping. Opt for 3/4″ x 2-1/2″ spruce instead.
Avoid using it.
For more durability, you should use stiffer strips, like a furring strip, and place them every 12 inches. Otherwise, it might start sagging in high temperatures.
I wouldn’t recommend using that torn press wood you have there because it might sag in the future. Opt for 1×4 instead, it will stay sturdy.
Was on board with the idea. I might even use treated wood for the outdoor project.
Why are you opting for particle plywood for the cross braces?
They’re just furring strips, Rob. I have 2x12s for the cross bracing.
You’re installing the soffit in the wrong direction… If you want it to run that way, you’ll need to secure something sturdy to nail into.
Place 2×4 pieces flat between the joists every 2 feet minimum, or adjust the soffit orientation accordingly.
The material of your fit strips is incorrect. Consider using strapping with spacing of at least 16 inches on center.
The fasteners are too big for the span. Try using roofing nails instead.
Metal is the way to go, not vinyl!
It’s actually recommended to run it perpendicular to the ceiling joists, and the soffit shouldn’t overlap in that manner.
How am I supposed to install it over 20 feet?
It’s been about 10 years since I sold my siding business, so I’m not sure what’s currently on the market. But we used to butt two pieces of soffit channel against each other where your seam is located. You might be able to find something similar in vinyl at a supply house.
If the ceiling measures 20’x20’, divide it at 10’ using this method. Make sure to extend it from the house to the eave, perpendicular to the joists. It not only enhances the appearance but also eliminates the need for furring strips.
Update on my previous message. Opted for the H channel.
Try running it the short way (perpendicular to the ceiling) instead. Any particular reason for using furring strips? I also observed that the nails are excessively tight.
Try using back to back J channel at the seams to avoid any visible seams.
That’s not the right way to tackle soffit.
OP is actually working on a ceiling, not soffit.
Mentioned they’re working on a ceiling using soffit materials. It’s okay for it to overlap, just like siding. It would look better if done in full pieces. I have experience installing siding for over 20 years, and double j-ing the seams would not look good.
If you trim the nailing strip and the hook about an inch back, it’s similar to cutting siding.
Hey, do you think using an H CHANNEL would be a good idea? I believe that’s what meant.
Using J channel back to back is another option. While overlapping soffit can technically “work,” it usually doesn’t look very good. To achieve better results, locate the center of your ceiling, snap a line down the middle, and install the J channels on the line. You’ll be much more satisfied with how it turns out.
Suggested cutting it into thirds if you’re a fan, but it’s up to you!
How wide is the material you’re using? In our area, we typically opt for 16″ widths for shorter runs and 8″ widths for longer spans. Whenever we tried using 16″ on longer spans, we always experienced sagging issues.
Seems like it could be a bit flimsy. Is it made of vinyl? You may want to consider adding a nail in one of the ribs.
In the best-case scenario, you’d want furring strips every 12-16 inches and ensure that seams align with the centers of supports. Personally, I would have run it the opposite way and included furrings along the entire nail strip.
Make sure to run it perpendicular to the joist and create breaks on a sturdy surface for nailing.
I’ve been in a similar situation before. It’s best to avoid potential issues in the future. I removed mine after 3 years. Consider switching to hardie board or a more rigid material.
I really appreciate the idea of using hardie board. What made you decide to remove the vinyl? What issues did you encounter?
‘s hair was super wavy, he couldn’t keep it in place. There were plenty of firing stops for fastening points. When I removed it, I discovered that the original installer had used drywall screws, which were rusting due to the coastal environment. As a solution, I now only use 308 or 316 grade stainless fasteners.