How to Apply a Scratch Coat on Brick or Stone Surface

What You'll Need
A clean paintbrush
A cleaning brush
A dry cloth
A plasterer's rake
A commercial brick or stone cleaner
A trowel
A high quality concrete bonding agent
A bucket of warm water
A large empty bucket
Stucco mix

Applying a scratch coat to your home's stone or brick surfaces may strike the casual household handyman as a dauntingly complex chore, but rest assured, it is a fairly simple procedure that virtually anyone is capable of completing in a timely fashion. This helpful set of instructions will walk you through the scratch coat application process in a step-by-step fashion and dramatically simplify what once seemed like a home improvement task best handled by high-priced professionals.

Step 1 - Thoroughly Clean Your Brick or Stone Surface

Before you can begin applying a scratch coat, you must first make sure your brick or stone surface is spotless. This task is best accomplished with the aid of warm water, a cleaning brush and a commercial brick or stone cleaner. Alternatively, soap can be used in place of a commercial cleaner if your surface isn't particularly dirty. Use your brush to vigorously scrub the surface, taking care to eliminate any caked-on dirt or debris. As is the case with most home improvement tasks, cleanliness is job one. Once your brick or stone surface is sparkling clean, you may use a cloth to dry it off or simply take a break and allow the surface to dry on its own.

Step 2 - Apply Your Bonding Agent

Now that your brick or stone surface has undergone a thorough cleaning, it is safe to apply your concrete bonding agent. With the aid of your paintbrush, spread the bonding agent across your surface using back-and-forth strokes. Once the entire surface has been covered, allow the bonding agent to have one hour of drying time. If you're still bursting with energy and don't feel like taking a break quite yet, you're in luck--you can perform the next step while waiting for the bonding agent to dry.

Step 3 - Prepare the Stucco

Now that your bonding agent has been applied, it's time to prepare your stucco. Consult the stucco's packaging to determine how much water you'll need, place the stucco in a large bucket along with the recommended amount of water and mix them together. Once your stucco has been sufficiently mixed and your bonding agent has been given ample time to dry, you'll be ready to proceed with the next step.

Step 4 - Apply Your Scratch Coat

Having mixed your stucco and allowed your bonding agent to fully dry, it's time to move on to the final step. Using your trowel, carefully spread a quarter-inch coat of stucco over your brick or stone surface. Once the stucco has been applied to the entire surface, allow it to partially harden, then carefully scratch some lines in it with the aid a plasterer's rake. Give the stucco a full forty-eight hours of drying time and you're all done.