Cracking, shrinking, or pitted mortar may simply be a sign that it's time for point-and-tuck mortar replacement. On the other hand, it could indicate that major issues are occurring within the structure. If the mortar shows any sign or moisture or turns black, immediate brick or stone repair is called for. The images below clearly show that mortar will crack and flake to make room for water expansion. In the case of this particular walkway, it was completely saturated with moisture, but the grout was dry, cracking, separating, and shrinking.
The evidence suggested this poolside walkway / retaining wall needed regrouting. HOWEVER...(see next slide)
Once the grout was removed and stones lifted from the bed, it became evident that water permeation had been an ongoing issue.
Unfortunately, the former homeowner, hoping to improve the appearance of the home prior to the sale, applied modern mortar that entrapped the already-prevalent moisture beneath the surface. This eventually lead to massive stone and structure failure.
AN IMPORTANT NOTATION: It is important to determine the age and porosity of your brick or stone prior to choosing a mortar. Modern mortars are wonderful for modern brick; but can have catastrophic results on porous materials. Cleaning modern mortar off brick or stone is time consuming and therefore, expensive.
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1) Check the Face of your Masonry Feature
a. Check the surface for granulation, cracking, brittleness, or splitting
b. Check the face for signs of water, i.e., bleaching, streaking, or black watermarks
c. Check the base for evidence of deterioration - stone or brick granules, mortar debris, etc.
2) Check the Mortar
a) Check for cracked, pitted, flaking, or gaps.
b) Check the base of the feature for evidence of mortar debris.
3) Check Drainage
a) Check and clean each drain spout along a retaining wall
b) Check and clean chimney flashing and drain spout systems
c) If you column mailbox has a drainage system, make sure it is clean before winter begins
4) Carefully Examine your Masonry Feature at Ground Level
a) Determine whether moisture is reaching the bottom layer of grout
b) Determine whether moisture is reaching the bottom layer of brick or stone
c) Assess whether water is pooling in certain spots more than others
(A mason can help adjust the drainage incline along this section)
Save Time and Money - Perform Bi-Yearly Inspections:
It is important to check both masonry and stucco products on a bi-yearly schedule. First, in the spring, to see whether any previously unknown issues surfaced after the freeze/thaw cycle; and secondly during autumn, when we want to ensure that we aren't inviting trouble into holes, cracks, or defaced brick surfaces that can be expensive to repair if left untreated. This tactic saves valuable time and money.
Any masonry item is susceptable to water penetration along the base. Most masonry features rest on a concrete pad that keeps moisture from penetrating the bottom layer of mortar, but you may determine that water pools more in certain areas than others. Masons can help readjust the incline along the bottom of your masonry feature to prevent further exposure.
The Facial Component
It is a common misconception that stone cannot deteriorate. Both wind and water helped create The Grand Canyon; and masonry features also contend with these forces.
a) Check your stone or brick surface for cracking, granulation, flaking, splitting, or pitting.
b) Check the surface for discoloration, (i.e., water tracks, bleaching, darkening).
c) Check around the masonry feature for evidence of debris. This step can help you zone in on trouble spots.
If you locate any of the aforementioned issues, you will want to have the damaged stone or brick assessed and/or repaired before winter. Freeze/thaw conditions intensify erosional effects. Timely masonry repair helps keep the cost of brick repair and the cost of stone repair at a minimum. (This is a great time to check your outdoor fireplace, chimney, and outdoor kitchens, as well).
What to Watch For
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Brick Face Deterioration caused by using modern mortars with antique brick
When brick cannot expand upward and inward, it expands outward, ruining the finished face of the brick.
This chimney shows signs of moisture on the face of the brick. This can be caused by using sealants on porous bricks or unyielding mortar during point-and-tuck mortar replacement.
Retaining Wall Winter Checklist
Winter is nearly here and it is time to check our retaining walls. Especially important are the base and drainage spouts. This Outdoor Masonry Winter Checklist can help you determine the state of your masonry before winter storms are upon us.
Outdoor Masonry Winter Checklist
The most important consideration with masonry is Water Permeation. The illustration below indicates the most common entry points for moisture. Although a visual inspection of all you masonry should be performed bi-yearly, it is especially important prior to winter weather. If freezing conditions occur, moisture expansion can turn even a small hole or crack into a much larger one.
Retaining walls have drain spouts every 15 feet, give-or-take. These drains are especially important during rainy seasons and long winters because they prevent moisture from collecting on the wayward side of the retaining wall. Before winter arrives, be sure to use a long-handled brush to remove any debris and/or critter evidence that may have collected within during the summer. (For chimneys, check the flashing).