Repointing 101: How to Fix Brick Mortar
Sometimes you need to get stuck between a rock and a hard place
- Safety glasses
- Work gloves
- Dust mask (respirator)
- Chisel
- Hammer
- Mortar mix
- Water
- Plastic sheeting (optional)
Brick homes can pull off just about any look—classic, cozy, modern, you name it—but their charm only holds up if the mortar does, too. Even the toughest bricks won’t stand a chance if the stuff between them starts falling apart. Once the mortar cracks or crumbles, it’s only a matter of time before the bricks follow. Fortunately, fixing it is way easier (and cheaper) than most homeowners think.
Choosing the Right Mortar
You need to match your mortar to the original, or you’ll risk damaging the brick you’re trying to save. Start by checking the color and texture of the existing joints (the space between the bricks). Look in shaded or protected spots where the mortar hasn’t weathered as much. Next, consider the strength of the brick and mortar separately. Older brick usually calls for a softer mortar, so using one that’s too hard can actually crack the bricks over time.
For most brick repointing jobs, Type N mortar is the standard—at least on homes built in the last one hundred years. It offers strength and just enough flexibility for aging bricks. Type S is another common option; however, it’s usually only recommended if you need extra durability, like for foundations or retaining walls. And if your DIY project calls for that type of work, it’s best left to a professional.
If you’re not 100% sure, check with a local mason. Getting the mortar right is half the battle for a long-lasting repointing job.
Remove the Damaged Mortar
Focus on the areas where the mortar is cracked or crumbling. Using a masonry chisel and hammer, chip away at the joints with short, controlled taps. Angle the chisel inward to avoid nicking the brick face. Clear out around ¾ to 1 inch deep for the new mortar to grip, although the general rule of thumb is 2 to 2 ½ times the width of the joint. Always wear safety glasses, work gloves, and a dust mask—you’ll thank yourself once the dust starts flying.
Clean the Joints
Now that the mortar’s out, clean the joints. Grab a wire brush and go joint by joint, scrubbing with firm pressure to knock out any remaining grit or stubborn mortar bits. Focus on the edges and corners—spots that love to hang onto debris. For softer brick or light touch-ups, switch to a stiff-bristled brush to avoid scuffing the face. You don’t want to rush this part. Any leftover dirt and debris will weaken your bond.
Dampen the Brick
Dry brick ruins good mortar fast. Before mixing anything, check the wall. If it’s been baking in the sun, it’s probably too dry to work with. Fill a spray bottle with clean water and mist the brick faces and joints until they’re evenly damp, not dripping. For larger jobs, use a garden hose with a fine mist nozzle to cover more area quickly.
Mix the Mortar
Follow the product directions on your mortar mix. Ideally, you’ll start by pouring your dry mortar mix into a clean bucket. Slowly add water while mixing with a trowel. Stir until the texture is thick, smooth, and holds its shape—too soupy and it won’t stick, too dry and it’ll crumble. Experts often liken the perfect consistency to peanut butter.
Only mix what you’ll use in the next hour. Once you get the right consistency, let it rest for 10 to 15 minutes. A little water will rise to the top. Stir it back in, and the mortar is ready to apply.
Apply the New Mortar
Photo: ClarkandCompany / iStock / Getty ImagesScoop up a workable amount of mortar using your trowel, then press it into the vertical joints using a tuckpointing trowel. Start at the back of the joint and pack it forward. Apply steady pressure to fill the gaps. For deeper joints, make multiple passes to fill them completely.
Move on to the horizontal joints once the verticals in that section are done. Use the same technique—firm, consistent pressure and layering (if needed) for wider joints. Avoid overpacking since too much at once will make the mortar slump out before it sets.
Work in small, manageable sections to stay ahead of the mortar drying. Finish a few vertical sections, then their connected horizontals, before moving on. Keep a bucket of clean water and a damp sponge or cloth nearby to wipe away any mortar that gets onto the brick face. Dry mortar stains fast and is a pain to remove, so remember to clean your brick as you go.
Finish the Joints
Let the mortar firm up (for around 30 minutes) until it’s “thumbprint hard”—press your thumb into it, and it should leave a shallow mark without sinking in. Grab your jointing tool (also called a jointer) and match the new mortar to the style of the original joints, for example, concave, V-joint, or weathered. Run the tool along each joint with even pressure to compress the mortar into your desired style and seal it tightly. After tooling, use a stiff brush to sweep away any leftover mortar.
Curing the Mortar
Slow down the drying to give the mortar time to cure properly. Mist the joints twice a day—more often in dry or hot weather—for the next two to three days. For extra protection, drape plastic sheeting loosely over the area to slow evaporation and protect the mortar from the elements.
Mistakes to Avoid
Mortar repair looks simple enough, but a few wrong moves will leave you with crumbling joints, stained bricks, or a patch job that clearly doesn’t match. If you want to save yourself a lot of backtracking, clean-up, or extensive brick repairs, here are common mistakes you should avoid:
Don’t re-wet drying mortar mix: Never add water once the mortar starts drying and stiffening. Scrap it and mix a fresh batch instead.
Don’t skip color matching: Compare your mix with the existing joints and adjust the pigments or mortar blends if needed. Reach out to a professional for a close color match.
Don’t use sealant as a replacement: Sealant won’t solve structural problems. Repointing with fresh mortar is the only lasting fix.
Don’t leave surfaces unprotected: Cover nearby surfaces with plastic sheeting or drop cloths to avoid unwanted stains.
Don’t use the wrong mortar: Check that you’re using the correct mortar type to match the brick and environment.
For anything involving structural concerns, historic brickwork, or unclear mortar types, call in your local professional mason. They have the tools, experience, and training to handle complex brickwork without risking your wall’s stability or appearance.
When to Fix Brick Mortar
Plan your mortar work for spring or fall, when the weather gives you your best chance at a strong curing process. Stick to temperatures between 50°F and 80°F—if it's too cold, the mortar won’t set right, and if it's too hot, it’ll dry out before bonding properly. Avoid rainy days and high humidity. Wet weather can wash out fresh joints or mess with curing. During warmer months, work early or in the shade, and keep your materials damp. If you monitor the forecast, prep your materials, and time it right, you won’t have to worry about repointing your brick for 30 to 50 years.
DIY vs. Hiring a Pro
A DIY brick repair can save money, especially on small to medium fixes. One 80-lb bag of mortar costs less than $20 and often covers enough for medium-sized projects. Instead of money, your real investment is time—removing old mortar, prepping joints, and curing add up. A smaller section might eat up your Saturday, while larger jobs can drag across the weekend.
If you hire an expert, the cost to repair brick averages $20 to $40 per square foot. For a 50-square-foot wall, that's around $1,000 to $2,000. Again, it's always worth hiring a professional for structural work on foundations or retaining walls—mistakes in these areas can compromise your home’s stability. For cosmetic touch-ups or small non-load-bearing walls, DIY is a solid option if you’re patient, detail-oriented, and looking to save on the cost of labor.
Frequently Asked Questions
Technically, yes, you can put new mortar over old mortar as long as the mortar isn’t damaged; however, that’s rarely the case. Cracked or crumbling mortar won’t give the new mix a solid base to bond with, which means you’re setting yourself up for a short-lived patch job. Skip the shortcut. Chisel out at least ½ to 1 inch of damaged mortar, clean the joints, and dampen the area before repointing. That’s how you get the results to stick—literally.
The mortar between your bricks is crumbling because it’s likely taken a toll from water, time, or poor installation—or all three. Moisture seeps into the joints, freezes, expands, and slowly breaks down the structure. Add in decades of weather exposure or a weak mix, and it’s no surprise the joints start to fail. Even subtle shifts in your home’s foundation can stress the mortar enough to crack and flake. Addressing the issues early, especially during installation, prevents more serious damage and helps preserve your brickwork.
Get our Angi-powered app
