Matching brick mortar involves careful observation and, often, professional assistance to ensure a seamless repair or addition to existing brickwork. Here's how you can effectively match brick mortar:
1. Obtain a Sample:
- Carefully extract a small, representative sample of the existing mortar. Avoid damaging the surrounding bricks. A small chisel and hammer can be helpful.
- The sample should be large enough for visual comparison and, ideally, for testing (about the size of a quarter is generally sufficient).
2. Consult Professionals:
- Visit a Local Brickyard or Masonry Supply Store: This is your best bet. Take your mortar sample to a reputable brickyard or masonry supply store. Their experienced staff can visually assess the color, texture, and composition of your sample and help you find a close match.
- Bring Photos: Supplement your sample with clear, well-lit photos of the existing brickwork, showing the mortar joints in context. This helps the professional understand the overall aesthetic.
- Describe the Mortar's Characteristics: Be prepared to describe any noticeable characteristics of the mortar, such as its color when wet versus dry, its texture (sandy, smooth, etc.), and whether it appears to contain any special additives.
3. Color Matching Techniques:
- Visual Comparison: The initial step involves visually comparing your mortar sample to various pre-mixed or custom-blended mortar options.
- Custom Tinting: If an exact match isn't readily available, many brickyards offer custom tinting services. They can adjust the color of a base mortar mix to perfectly match your sample.
4. Choosing the Right Mortar Type:
- Consider the Brick Type: The type of brick used in your structure dictates the appropriate mortar type. Softer bricks require softer mortars (lower compressive strength) to allow for expansion and contraction without damaging the brick.
- Mortar Type Designations: Mortar types are designated by Roman numerals and letters (e.g., Type N, Type S, Type M, Type O). Each type has a different compressive strength and is suited for different applications. Consult with a professional to determine the correct type for your project. (Type N is often a good general purpose choice).
5. Matching Gray Mortar:
- If your mortar is gray, you might be able to find a reasonable match with premixed bags of gray mortar available at most home improvement stores. However, variations in shade and aggregate can still be noticeable.
6. Test Patch:
- Before committing to a large repair, create a small test patch in an inconspicuous area. This allows you to evaluate the color match and the mortar's workability under real-world conditions.
Important Considerations:
- Mortar Color Changes Over Time: Mortar color can change due to weathering, efflorescence (salt deposits), and exposure to pollutants. Matching the existing color perfectly may be impossible, but aiming for a close match is the goal.
- Aggregate Size and Type: The size and type of sand used in the mortar mix significantly impact its texture and appearance. Pay attention to the aggregate in your sample and try to replicate it in your replacement mortar.
- Mortar Joints: Try to replicate the existing mortar joint profile (concave, flush, raked, etc.) for a more seamless appearance.
- Safety: Wear appropriate safety gear (gloves, eye protection) when working with mortar.
In summary, matching brick mortar requires a combination of careful observation, professional consultation, and potentially, custom color blending to achieve a visually appealing and structurally sound result.
