As This Old House senior technical editor Mark Powers demonstrates, installing the blocks requires just a few basic tools and a rented saw for cutting through the asphalt. (A little muscle for lifting the blocks helps, too.) Plant colorful flowers beside the edging when the weather warms up and you’ll love how this project makes your whole front yard feel more spiffy. Shown: 11x7x4 Belgian block stones, around $4 per block at stone yards.
Overview of How To Install Belgian Block Driveway Edging
Project Timeline: Friday: Cut and prep the driveway’s edges. Saturday: Dig the trench and lay the stones. Sunday: Finish laying the stones and backfill with soil.
1. Secure a Chalk Line
The edges of an asphalt driveway need to be cut straight so that the blocks line up evenly against it. Use a chalk line to mark the cuts. Lay a line near the edge of one side of the driveway. Next to the line, hammer nails partway into the asphalt, one at each end of the driveway and a few along its length, about 5 feet apart. Tie the line to the nail at one end, then pull the line taut as you loop it around the other nails along the edge, making sure it still rests on the asphalt’s surface.
2. Mark the Cut Line
Snap the chalk line between each secured point to leave a clear, straight mark to follow when cutting the asphalt.
3. Cut the Edges
Using a concrete saw, cut the asphalt along the chalk line. Don’t bother trying to hold the saw level; instead, let it sit on the asphalt and rock it forward to cut one small section at a time. To keep dust down, attach a hose to the fitting on the saw and run water through it as you cut, or have a helper hose down the asphalt in front of the blade while you’re working. Repeat all steps for the other side of the driveway.
Tip: Don’t let the saw penetrate the base course or soil under the asphalt, as this will dull the blade. Asphalt drives are usually 3 to 4 inches thick; gauge yours as you work so that your cuts don’t go too deep.
4. Remove Excess Asphalt
Wedge a spade into the cut line and pry the waste asphalt away from the side of the driveway.
5. Break Up Waste Prior to Disposal
To make the asphalt easier to get rid of, split it into chunks about 1 foot long, using a brick set and a maul.
Tip: Most trash collectors won’t take asphalt waste. To get rid of it, contact local asphalt producers; they often recycle it.
6. Clean Up and Back-Cut the Rough Edges
In spots where the asphalt was thicker or wasn’t cut cleanly, use a brick set and a maul to remove loose or stray chunks. Hold the brick set at an angle slightly off vertical as you work; this will undercut the surface slightly for better adhesion of the mortar. Repeat all steps for the other side of the driveway.
7. Dig the Trench
Use a spade to dig a trench next to your driveway that’s several inches wider than your blocks so that it can hold enough concrete to keep them in place. For stability, no more than half the blocks’ height should project above the asphalt’s surface, so the trench’s depth should be at least half the blocks’ height, plus 1 inch to make room for adding concrete below them. (For better drainage in areas prone to frost heave, dig the trench a bit deeper and tamp in a layer of crushed stone.)
8. Stake a Level Line
Drive a stake at each end of the trench. Measuring from the driveway’s surface, mark the desired height of the blocks above the asphalt on both stakes. Tie a mason’s line to one stake at the marked line, pull it taut, and secure it at the mark on the other stake. For long or unevenly pitched driveways, place additional stakes at the midpoint and as needed along the trench’s length, and tie the line to each one at the proper height. Repeat all steps for the other side of the driveway.
9. Add Concrete to a Short Section of the Trench
You’ll install the edging in 5- to 10-block sections, filling the trench with concrete as you go.
First, lay 5 to 10 blocks side by side next to the trench to determine the length of the first section. Mix concrete to a stiff consistency (it should hold together like a snowball if you ball it up in your hand). Using the spade, add a 1-inch layer to the first section of the trench.
10. Install the First Run of Blocks
Set the first block in place, wiggling it into the concrete slightly until it’s level and sits against the edge of the driveway. Tap the block with a rubber mallet until its top is even with the height of the level line. Repeat for the remaining blocks in the first section, making sure they’re flush with the level line and one another.
11. Add Concrete to Stabilize the Blocks
Using a mason’s trowel, fill the trench behind the blocks with concrete, mixed to a stiff consistency, until it’s level with or slightly higher than the asphalt’s surface. With a pulling motion, smooth the concrete against the back of the blocks at an angle until the top of the concrete sits about 2 inches below the top of the blocks.
12. Finish Installing the Edging
Keep laying the blocks until the runs on both sides are done. Once all the blocks have been installed, use a push broom to sweep paver base into the joints between the blocks and between the blocks and asphalt. Backfill the trench with topsoil, which will help the concrete dry more slowly, resulting in a harder cure. Full curing may take up to a week, depending on the weather.
13. Landscape the Border
When it’s warm enough, add colorful flowers and plantings next to the edging. Avoid varieties with extensive root systems that could nudge the blocks out of place.