Good morning and welcome to Saturday Morning Home Repair Blogging.
SMHRB is where we gather every Saturday morning to share frustrations, questions, possible solutions, and general wisdom about keeping our dwellings in good shape. Everyone is welcome and you should feel free to ask questions. Hopefully, the collective expertise here can help you out with your own projects.
I'm Milly Watt, serving as guest host for today's edition. While the SMHRB crowd includes many expert professionals and skilled DIY'ers, I fall into the "determined amateur" category. For the project I'm describing here, maybe I'm just a design consultant.
This is my second installment on the topic of landscaping with rocks. This one could be entitled "Fifteen tons, what do we get" and talks about our terracing project with the 15 tons of basalt that I got Mr. Watt for his birthday.
Mr. Watt chooses his first rock off the pile of raw material
Follow me below the orange pillow basalt.
When we were shopping for land to build upon, our first impression of our property was that it was probably unbuildable. Among other things, it's very steep. Obviously, we found a way to build our house. However, we ended up with a very challenging front yard. Walking across the yard on the wet grass (we're in the Pacific NorthWet) felt more like skiing downhill (and I often ended up on my butt). So, we needed to build terraces.
To make matters more difficult, we wanted to get our fruit trees started in our first year here. So we planted three trees right away and now we have to terrace around them. On the upside, we harvested 75 apples this year and enough pie cherries for one nice pie. On the downside, it makes working with big heavy rocks that want to roll downhill much harder.
Basalt rock is the local material of choice for terracing projects. Everywhere one goes in town, there are retaining walls built from rough, randomly shaped, basalt rocks. We already had a retaining wall that the excavator built with huge basalt rocks when putting in our driveway. So, we chose to go with that style for the terraces above it, but with smaller rocks that didn't require heavy equipment to manage. We ordered "half man" sized rocks from a local quarry. One definition I found says "A typical Half Man rock ranges in size from a large melon to a watermelon", although many of the rocks in our pile seem bigger. Basalt comes in various forms, including rounded "pillow" basalt and angular basalt. We seem to have a mix.
The planning phase benefitted from our having several perspectives: looking up from the driveway below the slope, looking down from the walkway above, and an almost aerial view from our second floor windows. I laid out contours on the ground with hoses and marked the potential route of each wall. We started with the upper terrace to get experience with both laying down the bottom course of rock and stacking the upper layers. With the top wall partially done, we started laying out the lower wall. I took photos from above of the hose route and its location relative to the fruit trees and the upper wall. Then, I futzed with photos to make the curves look a bit better. The white line was drawn over the path of the hose and the red corrections seemed to parallel the upper wall better.
Photoshopped plan of bottom wall
The plan translated to the bottom layer of stone
The walls are dry stacked with no mortar -- only gravity holds the rocks and what's behind them in place. Our walls will be about two feet tall. The base layer gets the biggest rocks. It's also convenient that oddly shaped rocks can go in the base layer and have their ugly sides dug down into the dirt. Retaining walls lean back into the slope they are supporting. This lean is called the "batter." A typical batter is about 2 inches for every foot of height. Mr. Watt built a batter gauge to maintain the batter we chose which leans a bit more than necessary.
Mr. Watt and his batter gauge
The next courses of rock are trickier. You want the nice flat faces showing on the outside. The joints between courses should be staggered. The rocks should fit together at least well enough to be stable. The top course needs both a nice outward face and a nice top. Picking one rock from the pile to satisfy all these criteria for a particular spot can take a good eye, some imagination, and quite a lot of time. Even when you've found a very good candidate, it can take some shaping with the chisel to fit in place to the level of perfection one is trying to achieve. And then one wrong whack and the almost perfect rock can shatter!
Shaping rocks to fit "perfectly"
Here are two useful books for stone projects that we used and recommend:
Stone Primer by Charles McRaven and
Landscaping with Stone by Pat Sagui. The first one focuses more on working with stone as a material and it's clear that the author is somewhat of a perfectionist. The second one has lots of inspirational landscape photos.
Here's one of our (hopefully) inspirational photos:
A completed section
Again welcome to SMHRB. The shop is now open.
What are you working on? What problems do you need help with?