How to fix concrete step corners that have broken off in NB?

Broken concrete step corners are one of the most common repair requests for NB homeowners, and for small to moderate corner breaks, it is one of the more manageable DIY concrete repairs — provided you use the right materials and respect the seasonal window for application.

Step corners break off in NB primarily because of freeze-thaw cycling combined with de-icing salt. Salt-laden slush on steps creates more freeze-thaw cycles at the concrete surface than the ambient temperature alone would produce. Water penetrates the concrete, freezes, expands by 9%, and eventually pops off the corner — usually right at the outer edge where the concrete is thinnest and most exposed. Steps poured without proper air entrainment deteriorate especially quickly.

For a DIY corner repair, here is the correct approach. First, chip away all loose and delaminated material from the break until you reach solid, sound concrete — this usually means making the repair area slightly larger than the break itself. The edges of the repair area should be as close to vertical as possible (not feathered) to give the patch mechanical grip. Clean out all dust and debris with a stiff brush and pressure wash if possible. Let it dry completely.

Apply a concrete bonding adhesive (like Quikrete Concrete Bonding Adhesive or SikaLatex) to all exposed surfaces of the repair area and let it become tacky — typically 15 to 30 minutes. Then apply your patch mortar. For step corners, Quikrete Vinyl Concrete Patcher or Sika MonoTop are better choices than standard ready-mix: they have polymers that improve adhesion and flexibility, which is important for a repair that will flex with freeze-thaw cycles. Mix to a stiff, almost dry consistency — too wet and it will slump off a vertical corner.

For the corner shape, you will need a form. A piece of lumber held against the riser face of the step, held in place with a brick or clamp, gives you a flat face to work against. Pack the mortar firmly into the corner, work it against the form, trowel smooth the top surface, and hold the form in place for at least an hour. Strip the form and finish any rough edges with a damp sponge.

Cure the repair for at least 72 hours before foot traffic, and do not apply any de-icing products for the first winter season. Sand is the safest option for traction on repaired steps in NB.

If the corner break is large — more than a few inches in any dimension — or if multiple step corners and risers are deteriorating across the full set of steps, the more cost-effective solution is often replacing the entire step unit. Professional concrete step replacement in NB runs $1,500 to $4,000 for a typical front entry set with 3 to 5 steps and a landing, and new air-entrained concrete poured correctly will outlast patched old steps significantly.