Tuck-pointing

Masonry homes and walls constructed of brick and stone can develop

voids, cracks, crumbling mortar, or uneven areas of mortar from settling

or foundation problems. Separations between brick and mortar can allow

air and water to leak through gaps in the wall. Repairing cracked mortar is

called tuck-pointing.

Tuck-pointing is typically needed when exposure (of 25-30 years) causes

mortar joints to crack, flake, or disintegrate. Large holes and washed out

mortar are typical signs that tuck-pointing is needed.

Although the right material and technique are usually enough to deliver a

water-tight job, it usually takes the skill of experienced professionals to use

the proper mortar mix and tools to match existing mortar.

The U.S. Department of the Interior Office of Historic Preservation has

established

standards to preserve the appearance of older buildings and to avoid

irreparable

damage during repointing and in the future. Often modern hard cement mortar

cannot

be used in older buildings because applying modern mortar over old lime

mortar can

result in serious damage to the original building materials and may not

last. It is

important that new mortar match the original in porosity and compressive

strength.