Brick Repointing and Brick Repair in Baltimore, MD

You can diagnose most of this yourself, with a screwdriver and a look from the sidewalk.

• The screwdriver test. Sound mortar resists a blade or thumbnail; failed mortar scrapes out in crumbs.
• Sand at the base of the wall, where mortar has broken down into sand.
• Recessed joints, more than about a quarter inch behind the brick face, holding water.
• Daylight or a draft through a joint, a direct path for water.
• Efflorescence, the white chalky bloom left when salt-bearing water dries on the brick face.
• Spalled brick: faces flaking, popping or crumbling, often from an earlier repoint in hard mortar.
• Stair-step cracking through the joints, from settlement or a rusting steel lintel.
• Damp patches inside on an exterior wall after driving rain.

Joints fail from the top down and on the weather side first: look hardest at south and west elevations and under overflowing gutters. Catch it there and you have a pointing job, not the brick repair Baltimore MD rowhouses need later.

Not sure what you are looking at? Send us a photo and we will tell you what it is. Call (410) 844-6510.

Mortar is meant to be the sacrificial part of a masonry wall, and that one idea decides whether a repoint protects your brick or ruins it. The National Park Service standard, Preservation Brief 2, puts it plainly: stresses should be relieved by the mortar rather than by the masonry units. Mortar stronger than the brick will not give, so the stress goes through the brick instead. Joints are cheap; brick faces are not.

Historic mortar is lime, not cement. The traditional mix is about 1 part lime putty to 3 parts sand. Portland cement was not in common use here until the early twentieth century, and by the 1930s the standard was equal parts cement and lime. So brick laid before about 1900 sits in nearly pure lime mortar, 1900 to the 1930s is transitional, and later work is cement rich.

Here is what goes wrong. Repoint soft old brick with modern bagged mortar and four things follow: movement is forced through the brick and it cracks; water cannot evaporate through the joint, so pressure pops the face off; salts crystallize inside the brick instead of at the joint face; and trapped water freezes and spalls it.

The visual signature of a wrong mix is hard joints standing proud of eroded, crumbling brick faces. Not reversible: spalled brick has to be cut out and replaced.

The mixes. Brief 2 recommends Type "L" (0 cement : 1 lime : 3 sand) for soft hand-made brick in sheltered exposure, Type K (1:3:10) for moderately durable stone, Type S (1:1.5:4.5) only for very durable granite. Historic Baltimore brick sits near the bottom of that scale, so the Type N and Type S bags at every supply house are far too hard. We match on strength, sand color and grain, and profile.

Formstone was patented in 1937 by L. Albert Knight of Baltimore's Lasting Products Company and went up across the city from the 1940s through the 1960s. Baltimore became the Formstone capital of the world; John Waters called it the polyester of brick.

How it is built. Three coats of cement stucco over perforated metal lath nailed into the brick, the top coat sculpted into stone shapes and scored to fake joints.

Why it damages brick. The lath separates from the brick and moisture gets trapped in the gap. Over porous nineteenth-century brick that means cracking, spalling, efflorescence and loosened joints, accelerated by freeze-thaw. It also buried the cornices, belt courses, lintels and sills built to shed water.

Removal is destructive, and you should hear that before you sign anything. Pulling it off pock-marks the brick face where the lath was nailed. What follows is cleaning, extensive repointing and usually brick replacement. Removal is the cheap part; the brick facade repair Baltimore homeowners pay for is everything after it.

Sometimes the right answer is to leave it in place. If the Formstone is sound and the brick behind it is soft salmon brick, removal can cost more than the house gains and trade a stable wall for a fragile one. We will tell you honestly which you have.

There is no shortcut to repointing brick Baltimore MD winters have worked on for a century. Seven steps, every time.

1. 01Assessment. Date the wall, identify the brick, test the mortar, find the water source. Repointing while a gutter still dumps on the wall wastes money.
2. 02Mortar match. Strength to suit the brick, then sand color and grain matched so the work does not read as a patch. This is where the brick restoration Baltimore rowhouses deserve either succeeds or fails.
3. 03Cutting out. Joints cut to a sound depth, generally two to two and a half times the joint width, square-backed, not feathered. Hand tools on soft brick.
4. 04Cleaning and pre-wetting. Dust brushed out, joints dampened so the brick does not pull water from fresh mortar.
5. 05Filling in lifts. Deep joints packed in layers, each set before the next, not stuffed in one pass.
6. 06Tooling. Joint profile matched to the original: struck, concave, raked, weathered or flush.
7. 07Cleanup and cure. Protection from sun, rain and frost while the mortar cures, and a clean site each day.

We work throughout Baltimore City and Baltimore County. In the city, the brick repointing Baltimore rowhouse owners call us for clusters in the older districts: Fells Point, Federal Hill, Bolton Hill, Union Square, Butchers Hill, Ridgely's Delight, Reservoir Hill and Highlandtown. Each has its own brick and era, which is why we date a wall first.

In the county the stock is different but the problems rhyme. We cover Catonsville, Towson and Dundalk among others, where 1940s and 1950s brick is at prime pointing age. Read more about our crews.