I'm working on a house that has Hardie Board siding, and I've noticed that a lot of the pieces at the bottom are loose. I thought the installation should be tight if done correctly. Could the issue be that nails missed the studs, or are there not enough nails used? Maybe the wrong kind of nails were used? I suspect it could also be related to installation gauges not being used properly. I noticed they had two different crews working on each side, and the exposure varies quite a bit, from 6-1/4 inches to 5-7/8 inches on 7-1/4 board. Shouldn't the inspector have caught this? Plus, since the nails are hidden, if I need to replace a piece, the nails would be exposed. I don't have a ton of experience with this stuff, but it all feels off. Any advice?
2 Answers
It sounds like you might be missing a strip of siding underneath the first board. That part is meant to be installed first, so it can be properly nailed down and support the bottom board. If they skipped that step, the board could end up floppy. You can also secure that board with some almost invisible finish nails if needed. It's also important to add a strip over the windows and doors as well to tighten things up. That could definitely help with any gaps!
I've heard you can even use a piece of Hardie as a starter to help with stability too.
Check out the Hardie installation manual, as they only allow top nailing depending on the wind zone. It might clear up some of your confusion about the installation. Unfortunately, the varying reveals you mentioned sound like sloppy workmanship. Most inspectors won't flag this unless it's really jacked up. Ultimately, you're responsible for making sure it meets Hardie's guidelines, so keep an eye on that!
Yeah, they definitely should have put a strip above the windows and doors. That makes a big difference in sealing the edges better.