Building a Footing for a Stone or Brick Wall
Whether you're building a brick wall, a stone wall, or any other wall that requires mortar, the job starts underground with a footing. A mortared wall is rigid and won't flex as the ground moves with seasonal changes. Without the footing, the wall would crack, and weather would compound the damage. With a footing, the wall sits on a strong, rigid platform. If the ground shifts enough to move the platform, the platform and wall move as one piece, minimizing cracks.
- LAY OUT THE EDGES OF THE FOOTING WITH BATTERBOARDS AND MASON'S LINE
- LAY OUT THE OUTSIDE OF THE FORMS
- ATTACH THE FORMS TO THE STAKES
- DRIVE STAKES EVERY 2 FEET
- MIX THE CONCRETE
LAY OUT THE EDGES OF THE FOOTING WITH BATTERBOARDS AND MASON'S LINE
The footing should be as thick as the wall it supports and twice as wide. Stretch mason's line to lay out the width, then use sand or flour to lay out lines on the ground that are 4 to 6 inches outside the lines. Measure the distance between the ground and the mason's line and write it on the batterboard for reference later. Mark the positions of the lines on the batterboards, then untie the lines. Start the trench at the lines you made on the ground, then dig it about 3 inches deeper than the wall is wide. If the ground freezes where you live, dig down at least 6 inches below the frost line. In either case, line the trench with an inch of gravel, and tamp it down.
LAY OUT THE OUTSIDE OF THE FORMS
The lines you originally tied to the batterboards marked the inside edge of the forms. Move them 1 1/2 inches closer to the outside edge of the trench in order to mark the outside edge of the form. Drop a plumb bob from the line and mark the end of the foundation with a nail put through a piece of paper. Drive stakes into the ground just outside the nails and run mason's line between them. Drive the stakes no more than 8 feet apart to ensure that the forms won't bow from the weight of the concrete.
ATTACH THE FORMS TO THE STAKES
Place a 2x8 against the stakes on each side of the trench. (Use 2x8s even if the footing will be deeper than 8 inches because excess concrete can flow underneath the form and make the footing stronger.) Measure down from the mason's line to make sure the board is both level and a couple inches below ground level [the distance you wrote on the batterboard in Step 1). Clamp the boards to the stakes and attach them. If you need to join two boards, drive a stake so it straddles the ends and nail it to both of the boards. For the ends of the form, cut 2x8s that are long enough to span the existing forms and the stakes. Attach each end to the forms and stakes. Trim all the stakes flush with the top of the form, using a handsaw. Apply form release agent to the inside surfaces of all the forms.
DRIVE STAKES EVERY 2 FEET
Lay a level across the form to make sure the sides are level. Hammer on the stakes as needed to adjust the boards. Drive in additional stakes flush with the top of the side boards every 2 feet along them. If two boards meet end to end, drive in a stake that spans the seams. Nail the stakes to the boards and trim them flush at the top. Concrete weighs enough to bend the boards outward when it's poured. Reinforce the forms with 1x2 spreaders nailed every 2 to 3 feet.
MIX THE CONCRETE
Mix pre-mixed concrete following the directions on the bag. Empty out the dry ingredients, then make a crater in the middle and pour in about half the required water. Fold the ingredients together and slowly add the rest of the water. Properly mixed concrete has the consistency of oatmeal. A more accurate way to test the mix is to smooth out the concrete and make grooves in it with a hoe. If the edges hold, the concrete is ready. If they fall in (like these did), add dry ingredients. If they crumble, add water.
DUMP CONCRETE IN THE FORMS
Set up a wheelbarrow ramp that leads to the edge of the form. Prop up the high end on a 2x4 or bricks. Resting it on the forms could knock them out of alignment. Pour the concrete into the form from the wheelbarrow, dumping one load up against another until the form is filled to the top. Work a shovel or spade in and out of the concrete to remove air pockets. Pay particular attention to corners and edges, where air often gets trapped.
SCREED THE FORM
Lay a 2x4 across the form and pull it along the length of the footing, shimmying from side to side and removing the spreaders as you go. This process, called screeding, levels and smoothes the concrete. Cover the footing with burlap and keep it damp, but not soaked, with water for two or three days while the concrete cures. The moisture keeps the concrete from drying too quickly and cracking.
REMOVE THE FORM
Once the concrete has cured, pull the nails out of the form. Work stakes loose with a crowbar and remove them, then gently pry the boards off the footing. Fill in around the footing with soil and tamp it firmly. Wait until you've finished the wall to replant.
Your quick rate has been submitted.
Please note it may take up to 8 hours for your quick rating to appear.
Sorry we are currently experiencing technical difficulties. Please try and resubmit your Quick Rating.
Skill Level: Intermediate
Time: 3 hours
Due to differing conditions, tools, and individual skills, The Home Depot® assumes no responsibility for any damages, injuries suffered, or losses incurred as a result of attempting to replicate any of the home improvement ideas portrayed in this website Before beginning any home improvement project, review it thoroughly to ensure you or your contractor can finish the project and if any doubts or questions remain, consult local experts or authorities. Because codes and regulations vary greatly, you always should check with authorities to ensure that your project complies with all applicable local codes and regulations. Always read and observe all of the safety precautions provided by any tool or equipment manufacturer, and follow all accepted safety procedures.