I'm working on building a retaining wall at my cabin to combat erosion, and I could really use some advice. My plan is pretty basic: I'm aiming for a U-shaped wall that follows the natural curve of the hillside. I've cleared out a flat area and will be laying down two rows of rocks—mostly basketball-sized granite and other durable local stones. I want to stack the rocks up in the middle of these rows and then backfill with dirt. I'm also thinking of using concrete powder to bind the rocks together. The final layer will be topped with crushed gravel and a firepit. However, I'm not sure how much or what type of concrete to use, and I have questions about drainage since the site is on a slope. I don't think I need to worry about washing away since I have plenty of rocks to work with. Any tips or pointers would be greatly appreciated!
4 Answers
Instead of bonding the rocks together, try to batter them, meaning set each layer back about an inch. You should backfill immediately behind the wall with gravel rather than dirt to help with drainage—and keep in mind, water and frost heave can really damage retaining walls. Not adhering the rocks means they'll be able to shift and settle without cracking, which is essential for durability. Also, make sure to trench down first and lay down a few inches of compacted gravel before placing your first course.
Sounds like a great project! Just a quick question though—what’s the final height you’re aiming for with this wall?
I'm looking at around 2 to 2.5 feet at the highest point, with the lower end being under 1 foot.
It might help to have a drawing of the area so people can visualize your project better!
Oh, and definitely check out specific subreddits for retaining wall projects—those are full of inspiration and can provide even more specialized advice!
That's a solid tip about the gravel! Just remember to consider how the water will flow around your wall as well.