What is tuckpointing?

What is the purpose of tuckpointing?

The purpose is to renew the mortar joints, which wear out long before the brick or stone does. Preservation Brief 2 says masonry deteriorates mostly at the joints, and that good repointing restores the wall while poor repointing can harm it: “Although generally considered "permanent," masonry is subject to deterioration, especially at the mortar joints.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Properly done, repointing restores the visual and physical integrity of the masonry.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Improperly done, repointing not only detracts from the appearance of the building, but may also cause physical damage to the masonry units themselves.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

What do the National Park Service and OSHA mean by tuckpointing?

Tuckpointing is the common name for repointing: cutting worn mortar out of the joints of a brick or stone wall and packing new mortar in its place. The National Park Service's repointing guide, Preservation Brief 2, notes the name is somewhat inaccurate, and OSHA uses it for grinding out mortar between bricks: “Repointing, also known simply as "pointing" or—somewhat inaccurately—"tuck pointing"*, is the process of removing deteriorated mortar from the joints of a masonry wall and replacing it with new mortar (Fig. 1).” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Tuckpointing technically describes a primarily decorative application of a raised mortar joint or lime putty joint on top of flush mortar joints.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Tuckpointing involves removing deteriorating mortar from between bricks using a handheld grinder and replacing it with fresh mortar.” Source: Occupational Safety and Health Administration, U.S. Department of Labor, read 2026-10-29. “Old mortar should be removed to a minimum depth of 2 to 2-½ times the width of the joint to ensure an adequate bond and to prevent mortar "popouts" (Fig. 8).” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

How do you know if you need tuckpointing?

HUD's Rehab Guide for exterior walls lists the signs, including mortar worn back more than 1/4 inch from the face, crumbling mortar and hairline cracks, and says a look plus a light scrape with a metal tool finds most problems: “Conditions that require repointing may include: mortar erosion more than 1/4 inch, crumbling mortar, and hairline cracks in the mortar and between the mortar and brick.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “Visual observation in combination with a light scraping with a metal tool can detect most deficiencies.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “The decision to repoint is most often related to some obvious sign of deterioration, such as disintegrating mortar, cracks in mortar joints, loose bricks or stones, damp walls, or damaged plasterwork.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

Does tuckpointing stop leaks?

Failed joints do let water into a wall, so new mortar can close that path. But Preservation Brief 2 warns that repointing alone does not fix water coming from leaking roofs or gutters, settling, rising damp or harsh exposure, and those causes come first: “At some point the mortar joint will fail, allowing water to enter the wall cavity.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “It is, however, erroneous to assume that repointing alone will solve deficiencies that result from other problems (Fig. 2).” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “The root cause of the deterioration—leaking roofs or gutters, differential settlement of the building, capillary action causing rising damp, or extreme weather exposure—should always be dealt with prior to beginning work.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Without appropriate repairs to eliminate the source of the problem, mortar deterioration will continue and any repointing will have been a waste of time and money.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

How long does tuckpointing last?

HUD's Rehab Guide gives a figure it credits to the brick industry: brick itself can last more than 100 years, while mortar joints last closer to 25 years, depending on how exposed the wall is: “While the service life of many types of brick can exceed 100 years, the longevity of mortar joints, depending on the exposure, is closer to 25 years, according to the Brick Industries Association (BIA).” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29.

How long does tuckpointing take to cure?

Preservation Brief 2 gives several time spans: burlap over the wall for the first three days, about thirty days before the new mortar is hard enough for cleaning, and several months before the joints are fully cured: “Walls should be covered with burlap for the first three days after repointing.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “New mortar joints are especially susceptible to damage because they do not become fully cured for several months.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “First, the mortar should be fully hardened before cleaning.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Thirty days is usually sufficient, depending on weather and exposure; as mentioned previously, the mortar will continue to cure even after it has hardened.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Once carbonation of the lime has begun, it will continue for many years and the lime will gain strength as it reverts back to calcium carbonate within the wall.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

Can tuckpointing be done in winter?

Preservation Brief 2 names a wall temperature window of 40 to 95 degrees F (8 to 38 degrees C). For cold weather it advises against antifreeze additives and says to warm the sand and water and keep the finished work from freezing: “Generally speaking, wall temperatures between 40 and 95 degrees F (8 and 38 degrees C) will prevent freezing or excessive evaporation of the water in the mortar.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “The use of antifreeze compounds is not recommended.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “A better practice is to warm the sand and water, and to protect the completed work from freezing.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

What type of mortar is used for tuckpointing?

The new mortar should be softer than the brick or stone and no harder than the old mortar. Preservation Brief 2 lists five ASTM mortar types from Type M at 2,500 psi down to Type K at 75 psi, and HUD names types N and O for more recent houses: “Mortars for repointing should be softer or more permeable than the masonry units and no harder or more impermeable than the historic mortar to prevent damage to the masonry units.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “To avoid serious brick damage the compressive strength of the repointing mortar should be similar to or weaker than that of the original mortar.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “Mortars used in more recent construction include types N and O (Table 1).” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “The ASTM designated them in decreasing order of approximate general strength as Type M (2,500 psi), Type S (1,800 psi), Type N (750 psi), Type O (350 psi) and Type K (75 psi).” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “Because masonry cements are not required to contain hydrated lime, and generally do not contain lime, they produce high strength mortars that can damage historic masonry.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29.

How loud is tuckpointing?

Preservation Brief 2 does not give a decibel figure, but it calls cutting out the old joints quite noisy and dusty. OSHA's silica rule for construction sets dust controls and respirator levels for workers who grind out mortar: “The joint preparation process can be quite noisy and can generate large quantities of dust which must be controlled, especially at air intakes to protect human health, and also where it might damage operating machinery.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “The process is time consuming, and scaffolding may need to remain in place for an extended period of time.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “The dust collection system must provide at least 25 cfm of air flow per inch of wheel diameter and have a filter that has a 99 percent or greater efficiency and either a cyclonic preseparator or a filter-cleaning mechanism.” Source: Occupational Safety and Health Administration, U.S. Department of Labor, read 2026-10-29. “Respiratory protection with a minimum APF of 10 is required for work with handheld grinders for mortar removal lasting four hours or less in a shift.” Source: Occupational Safety and Health Administration, U.S. Department of Labor, read 2026-10-29. “Respiratory protection with a minimum APF of 25 is required for work lasting more than four hours per shift.” Source: Occupational Safety and Health Administration, U.S. Department of Labor, read 2026-10-29.

Is tuckpointing structural?

HUD says repointing can strengthen walls as well as seal them, and Preservation Brief 2 explains that mortar is meant to take a wall's stresses so the bricks do not crack. HUD also says some wall problems need more than repointing: “Repointing walls can stabilize deterioration, strengthen walls, and provide weathertightness.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “Stresses within a wall caused by expansion, contraction, moisture migration, or settlement must be accommodated in some manner; in a masonry wall these stresses should be relieved by the mortar rather than by the masonry units.” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “A mortar that is stronger in compressive strength than the masonry units, will not "give," thus causing the stresses to be relieved through the masonry units—resulting in permanent damage to the masonry, such as cracking and spalling, that cannot be repaired easily (Fig. 5).” Source: National Park Service, U.S. Department of the Interior, read 2026-10-29. “There are certain conditions where repointing alone is not effective and replacement of a portion of a wall may be required.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29. “Serious structural problems require a professional engineer’s assistance in determining appropriate corrective measures.” Source: U.S. Department of Housing and Urban Development (HUD USER), read 2026-10-29.

Sources

• Preservation Brief 2: Repointing Mortar Joints in Historic Masonry Buildings — National Park Service, U.S. Department of the Interior; published 1998; read 2026-10-29.
• Small Entity Compliance Guide for the Respirable Crystalline Silica Standard for Construction (OSHA 3902) — Occupational Safety and Health Administration, U.S. Department of Labor; published OSHA 3902-02R 2024; read 2026-10-29.
• The Rehab Guide, Volume 2: Exterior Walls (section 3.3 Repoint Existing Walls and 3.4 Repair Existing Masonry Walls) — U.S. Department of Housing and Urban Development (HUD USER); published August 1999; read 2026-10-29.