This blog is a simple primer on how to fix bricks that have come loose at a step edge.
Often, the reason mortared material comes loose is because the brick, slate or stone was not backed correctly. In this case, a layer of compacted sand was laid, and then the bricks were mortared onto the sand–not the ideal method as concrete is a vastly superior backing. In the field areas (not the perimeter but in the middle) the flagstone is secure. This is most likeley because the mortar below it became monolithic (attached with all the other mortar below the stone) and formed a concrete-like surface while the bricks on the step edge were most likely done later. In any case, the lip of the bricks tests the stability of the mortared integrity every time someone steps on the cantaleivered edge, and in this case it failed.
Here’s how to fix the problem in four easy steps:
I) Dig out the sand and unstable material behind or under the brick. Dig down at least 4″ to provide a secure block of mortar to adhere to the rise of the step.
2) Use a spray bottle to dampen the entire area, including the backside of the brick. By dampening the area, you are helping the mortar and brick join. The mortar has Portland cement in it and will try to suck the water out of things around it–including your skin, so wear gloves if you have them. Fill the void with mortar to slightly below the height of the bircks. Mortar should be the consistency of brownie mix.
3) Once the area has set up you can lay brick. This could take an hour or two. For me, coming back the next day was not an option but would be ideal. Once firm to the touch, set the bricks. You can use a level or 2×4 and your own good judgement to make sure the bricks are algined and flush with the existing proximity surfaces. If you come back when it’s dry, wet the area again. If you don’t have a spray bottle, use a sponge or rag.
4) Mortar between the bricks. Push the mortar in with a trowel or putty knife. Carefully scrape off the excess and allow to set until firm–usually fifteen minutes or so, dependent on weather. Sponge off the bricks using a mortar’s sponge. Rinse the water often–if you don’t get all the mortar off now it will be difficult to get it off later.
Allow to dry and keep off of it. If you have dogs, try to keep them from tromping on your new step.
That’s it. Good luck with your home projects and remember to call Appleby for all your cleaning and restoration needs.