Chimney Repairs Blanchardstown

Perched at the highest point of your roof, your chimney stack absorbs the full impact of wind-driven rain moving across West Dublin. When the mortar joints between the bricks weather away or the lead flashing around the base cracks, water penetrates directly into the masonry.

From there, it tracks down internal flues, showing up as brown damp stains on upstairs ceilings, peeling paint, or musty smells around the chimney breast.

At AD Roofing, we provide complete chimney repair, repointing, and rebuilding services throughout Blanchardstown. From 1970s semi-detached and terraced builds in Hartstown, Huntstown, and Corduff to older properties around Blanchardstown Village, Augustine Doherty inspects every stack in person and handles the masonry and leadwork directly.

Chimneys in the Blanchardstown area face specific issues directly tied to their build age and construction type:

• Shared Party-Wall Chimney Leaks (Hartstown, Huntstown, Coolmine):

  Many houses in D15 share a central brick chimney stack sitting directly across the party wall dividing two properties. If the builder-grade lead aprons or step flashings installed decades ago have split, rain seeps beneath the tiles and travels down the shared party wall, making it tricky to diagnose which side is causing the issue.

• Washed-Out Sand-Cement Mortar (Corduff, Whitestown, Mountview):

  Stacks built in the 1970s and 1980s have faced more than 40 years of Irish winter freeze-thaw cycles. The original mortar joints crumble away into loose sand, leaving deep crevices between bricks. During sustained rain, water soaks straight into the core of the stack.

• Cracked Flaunching & Loose Chimney Pots:

  The flaunching—the sloping cement crown at the very top of the stack holding the terracotta pots in place—often develops severe hairline fractures. Once water freezes inside these cracks, the cement breaks apart, causing chimney pots to tilt precariously in high winds.

• Unused Flues Causing Internal Damp:

  Many Blanchardstown homeowners have blocked up open fireplaces or installed central heating and stoves without fitting ventilated cowls at roof level. Without heat rising to dry out the flue, unventilated chimneys trap humid air and rainwater, resulting in stubborn internal condensation and damp patches on interior walls.

We never apply temporary bitumen mastic or quick-fix sealants over damaged chimneys. We carry out trade-tested repairs that ensure long-term structural weatherproofing:

• Code 4 Lead Flashing Renewal: We replace cracked, torn, or lifted leadwork with new heavy-gauge Code 4 milled sheet lead. Each section is hand-dressed, securely wedged into the brick mortar joints, and sealed with dedicated lead-mastic sealant designed to expand and contract without cracking.

• Stack Raking & Repointing: We rake out failing, porous mortar to a depth of at least 15 to 20mm across all four faces of the stack. We then repoint using weather-resistant, polymer-modified mortar mixes that bond securely to the brickwork and seal out moisture.

• Flaunching Replacement & Chimney Pot Fitting: We chip away fractured, crumbling cement crowns, lay a solid waterproof concrete bed with clean water-shedding angles, and securely reset or replace chimney pots, cowl units, and bird guards.

• Stack Lowering, Removal & Rebuilds: If a chimney stack is leaning, severely fractured, or redundant, we can dismantle it brick by brick. If you want the chimney removed entirely, we take it down below the roofline, frame across the opening with treated structural timber, fit breathable underlay, and tile over the gap seamlessly.

• Ventilated Rain Cowls: We fit aerodynamic rain and bird cowls over active or disused flues to prevent rain pouring down the chimney bore while maintaining essential attic and room airflow.

Don't wait for minor mortar loss to turn into an expensive internal ceiling repair. Speak directly with Augustine Doherty today for honest advice and a free, fixed-price quote.