London's Rich Architectural Heritage
London, Ontario boasts a wealth of historic homes, from Victorian beauties in Old North and Woodfield to Edwardian gems in Wortley Village. While these homes offer character and craftsmanship rarely found in newer construction, they also present unique masonry challenges that require specialized knowledge to address.
Yellow Brick Deterioration
The London Yellow Brick Legacy
Many of London's historic homes were built using locally-produced yellow clay brick, particularly during the late 19th and early 20th centuries. These distinctive bricks face specific issues:
- Higher porosity than modern bricks, making them more susceptible to moisture damage
- Tendency to spall (flake or crumble) when exposed to freeze-thaw cycles
- Difficulty in finding matching replacement bricks for repairs
- Incompatibility with modern cement-based mortars
Preservation Approach
Proper care of yellow brick includes:
- Using appropriate lime-based mortars for repointing
- Applying breathable sealants when necessary
- Sourcing salvaged yellow brick for replacements
- Working with masonry specialists familiar with historic materials
Foundation Issues
Common Foundation Types
Older London homes typically have one of these foundation types, each with specific concerns:
- Rubble Stone Foundations: Found in pre-1900 homes, these often suffer from deteriorating mortar and shifting stones
- Brick Foundations: Common in early 20th century homes, these can experience moisture damage and mortar failure
- Early Concrete Foundations: These often lack proper reinforcement and may develop significant cracks
Signs of Foundation Problems
Watch for these indicators of foundation issues in older London homes:
- Stair-step cracks in exterior brick walls
- Mortar erosion near the foundation line
- Bulging or leaning foundation walls
- Persistent dampness in basement corners
- Uneven floors on the main level
Chimney Deterioration
Vulnerable by Design
Chimneys in older London homes are particularly susceptible to damage because:
- They're exposed to harsh weather from all sides
- They experience extreme temperature fluctuations when in use
- Many have deteriorated or missing caps, allowing water infiltration
- Original mortar has often reached the end of its lifespan
Common Chimney Issues
We frequently address these chimney problems in historic London homes:
- Deteriorated crown or cap allowing water penetration
- Spalling brick on the upper portions exposed to weather
- Cracked or missing mortar joints
- Leaning or unstable structures requiring rebuilding
- Damaged flue liners creating safety hazards
Inappropriate Previous Repairs
Modern Materials on Historic Masonry
One of the most common issues we encounter is damage caused by improper repairs:
- Portland cement mortar used on soft historic brick, causing brick damage
- Waterproof sealants that trap moisture within walls
- Painted brick that prevents natural moisture migration
- Mismatched replacement bricks that compromise aesthetic integrity
Reversing Damaging Repairs
Addressing these issues often involves:
- Carefully removing inappropriate modern mortars
- Repointing with historically appropriate lime-based mortars
- Removing damaging sealants when possible
- Sourcing period-appropriate materials for repairs
Preventative Maintenance
Owners of historic London homes can protect their masonry with these steps:
- Annual inspection of all masonry elements
- Prompt repointing of deteriorated mortar joints
- Maintaining proper drainage away from the foundation
- Addressing vegetation growing on or near masonry
- Working with masonry contractors experienced in historic preservation
At 519 Trough & Exterior, we specialize in preserving and restoring the masonry of London's historic homes. Our team understands the unique challenges of yellow brick, historic foundations, and traditional construction methods. Contact us for an assessment tailored to your home's specific needs.