Dawz84
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I had a small leak in the main water line before the stop tap in my 1950s house. The copper pipe had worn away over the past 70 years, causing a small crack in the copper.
A plumber/builder fixed the leak by digging a one-foot by one-foot hole in the corner of the property where the main water enters the kitchen. The area has been left to dry out for the past week or two, waiting for the plumber/builder to return and fill the hole.
During the repair, we discovered that the house, like many built in the 1950s, has a concrete subfloor with a 20mm asphalt layer acting as a damp-proof membrane (DPM). Considering the leak, the concrete is surprisingly dry. We believe the open service pipe below the concrete allowed the water to drain away.
The plumber/builder will be back soon to fill the hole, leaving a concrete surface flush with the existing floor.
Question: Repairing the Damp-Proof Membrane and Re-Tiling
My concern is how to address the asphalt layer, which previously served as the damp course before tiling. Its only 1-2ft square
I contacted Ardex, and their flooring technical specialist advised that minimal rising damp wouldn't be an issue with porcelain tiles. He recommended using Ardex NA, a moisture-tolerant product that bonds to both concrete and asphalt. He assured me it's flexible, accommodating any movement in the asphalt due to temperature changes. He then suggested using Ardex X7, a flexible tile adhesive, for laying the tiles back down.
While I trust Ardex's technical expertise, I'm tempted to add a few coats of bitumen paint (blackjack) on top of the concrete and then Ardex NA for extra moisture protection.
In another area of the kitchen, a couple of tiles have come loose (this happened before the leak was a separate issue). This area has channels for utilities built into the concrete floor. I suspect the different expansion rates between the new concrete channels and the existing asphalt, placed right next to each other, caused the tiles to lift. I believe no flexible products like Ardex NA or adhesive were used over these channels; the tiles were likely laid directly on top.
Seeking Confirmation from Tiling Experts
I'd appreciate confirmation from tiling experts on whether this approach is suitable for porcelain tiles. I trust Ardex's technical representatives, but a second opinion would be reassuring.
Thank you for any help or advice! This leak has been stressful.
A plumber/builder fixed the leak by digging a one-foot by one-foot hole in the corner of the property where the main water enters the kitchen. The area has been left to dry out for the past week or two, waiting for the plumber/builder to return and fill the hole.
During the repair, we discovered that the house, like many built in the 1950s, has a concrete subfloor with a 20mm asphalt layer acting as a damp-proof membrane (DPM). Considering the leak, the concrete is surprisingly dry. We believe the open service pipe below the concrete allowed the water to drain away.
The plumber/builder will be back soon to fill the hole, leaving a concrete surface flush with the existing floor.
Question: Repairing the Damp-Proof Membrane and Re-Tiling
My concern is how to address the asphalt layer, which previously served as the damp course before tiling. Its only 1-2ft square
I contacted Ardex, and their flooring technical specialist advised that minimal rising damp wouldn't be an issue with porcelain tiles. He recommended using Ardex NA, a moisture-tolerant product that bonds to both concrete and asphalt. He assured me it's flexible, accommodating any movement in the asphalt due to temperature changes. He then suggested using Ardex X7, a flexible tile adhesive, for laying the tiles back down.
While I trust Ardex's technical expertise, I'm tempted to add a few coats of bitumen paint (blackjack) on top of the concrete and then Ardex NA for extra moisture protection.
In another area of the kitchen, a couple of tiles have come loose (this happened before the leak was a separate issue). This area has channels for utilities built into the concrete floor. I suspect the different expansion rates between the new concrete channels and the existing asphalt, placed right next to each other, caused the tiles to lift. I believe no flexible products like Ardex NA or adhesive were used over these channels; the tiles were likely laid directly on top.
Seeking Confirmation from Tiling Experts
I'd appreciate confirmation from tiling experts on whether this approach is suitable for porcelain tiles. I trust Ardex's technical representatives, but a second opinion would be reassuring.
Thank you for any help or advice! This leak has been stressful.
