Brick is durable, but the mortar between the bricks is designed to wear out first. In New York, where walls go through repeated freeze–thaw cycles and wind-driven rain, mortar joints eventually crack, wash out and let water into the wall. Catching that early with repointing — removing deteriorated mortar and replacing it — is usually far less disruptive than waiting until bricks start loosening. Here are the signs to look for and what good repointing actually involves.
7 signs your brick needs repointing
1. Recessed or eroded joints
Stand close to the wall and look at the joints in profile. If the mortar has worn back noticeably behind the face of the brick, water sits on the little ledge it leaves behind and soaks into the wall.
2. Crumbling, sandy mortar
Mortar that powders or comes away easily when you run a key across it has lost its binder. A few soft spots may be normal on an old wall; widespread softness usually isn’t.
3. Cracks through the joints
Hairline cracks along joints let water in. Stair-step cracks that follow the joints diagonally can also point to movement, which should be looked at before simply filling the joints.
4. Missing mortar
Gaps where mortar has fallen out entirely are an open door for water, insects and further deterioration.
5. Spalling or loose bricks
When the face of a brick flakes or pops off (spalling), it’s often because water got into the masonry and froze. Loose bricks — especially at parapets, chimneys and around windows — need attention promptly, because falling masonry is a safety hazard.
6. Efflorescence
White, chalky deposits on brick are salts carried to the surface by moisture moving through the wall. Efflorescence itself is cosmetic, but it tells you water is getting in somewhere.
7. Damp or stained interior walls
Peeling paint, damp plaster or stains on the inside face of an exterior wall — especially after storms — often trace back to open joints, or to failed parapets and copings above.
Where to look first on an NYC building
- Parapets and chimneys. They’re exposed on both sides and take the worst of the weather. See our parapet guide for the City’s annual observation rule.
- Under copings, sills and lintels, where water collects.
- Corners and the top few courses of the wall.
- Stoops and areaway walls on brownstones and row houses.
- Exposed side walls on attached homes where the neighboring building is shorter.
What proper repointing involves
The National Park Service’s Preservation Brief 2: Repointing Mortar Joints in Historic Masonry Buildings is the standard reference on doing this well. A few principles from it are worth knowing before you hire anyone:
- Mortar should be softer than the brick. Repointing mortar should be softer (lower in compressive strength) than the masonry units and no harder than the historic mortar. When mortar is harder than the brick, the brick ends up cracking or spalling instead of the joint.
- Rake out to the right depth. The Brief calls for removing deteriorated mortar to a minimum depth of 2 to 2½ times the width of the joint, so the new mortar is properly anchored — not a thin skim on the surface.
- Protect the brick edges. Careless grinding widens joints and chips brick edges, which changes how the wall looks and how it sheds water.
- Fill in layers and tool the joint. Deep joints are packed in layers and tooled to match the existing joint profile so they shed water.
- Match the appearance. Color, texture and joint profile should match the original as closely as practical.
On older brick — common across Brooklyn, Manhattan and the Bronx — getting the mortar wrong can cause more damage than it fixes. A good contractor will explain the mortar they plan to use and why.
Repointing vs. rebuilding
Repointing works when bricks are still sound and well bonded. If sections are bulging, bricks are loose over a large area, or a parapet or chimney is leaning, those sections may need to be taken down and rebuilt. Badly spalled brick is usually replaced with a matching unit. An honest estimate separates these items so you can see what’s urgent and what can be planned.
Permits, landmarks and access
- Landmarks. If your building is an individual landmark or in a historic district, exterior work such as repointing generally needs a permit from the Landmarks Preservation Commission, which reviews mortar color, texture and joint profile.
- DOB. Whether DOB permits are needed depends on the scope and the building; DOB’s “Do I need a permit?” page is a useful starting point. Scaffolding and sidewalk protection may have their own requirements.
- Facade programs. Buildings higher than six stories fall under Local Law 11 / FISP — see our FISP guide.
When to schedule
Mortar needs suitable temperatures to cure properly, so major repointing is generally scheduled outside the coldest stretches of winter. If you notice signs in winter, it’s a good time to get an inspection and estimate so the work can be booked early in the season. Loose or falling masonry should not wait — that’s a safety issue.
Can you do it yourself?
Small, low, easily reached areas — a garden wall, a few joints at a stoop — are sometimes handled by experienced homeowners. Anything on an upper story, a parapet, a chimney or a landmarked facade is a job for a professional with proper access equipment and an understanding of mortar compatibility.
How PrimeCity can help
We provide brick pointing, repointing and facade repair across the five boroughs, including Brooklyn brownstones and row houses, attached homes in Queens and multi-family buildings in the Bronx. If water is already getting inside, we’ll also look at waterproofing details. We’ll look at the wall with you and explain what we see.
Frequently asked questions
How do I know if my brick needs repointing?
Look for mortar that is recessed, crumbling, cracked or missing; cracks running through joints; loose or spalling bricks; white efflorescence; and damp spots or stains on interior walls behind the brick.
Should new mortar be stronger than the old mortar?
No. The National Park Service’s Preservation Brief 2 says repointing mortar should be softer (lower in compressive strength) than the masonry units and no harder than the historic mortar, so the joint — not the brick — takes the stress.
Do I need a permit to repoint brick in NYC?
It depends on the scope and building. If the building is an NYC landmark or in a historic district, exterior work such as repointing generally needs a Landmarks Preservation Commission permit. Some facade work also needs DOB permits, scaffolding or sidewalk protection.
Official sources
- National Park Service — Preservation Brief 2: Repointing Mortar Joints in Historic Masonry Buildings (PDF)
- NYC Landmarks Preservation Commission — Permit types
- NYC DOB — Do I Need a Permit?
General information only — not legal advice. Requirements change; confirm details with the issuing agency.