Tanking Works to Fix 4 Leaking Underground Vaults in Mayfair, London
A privately-owned Mayfair, London building had 4 interconnected underground vaults which were all leaking.
After a previous supplier failed to solve the problem, Crown Preservation stepped in with a bespoke tanking and slurry solution.
Crown Preservation fixed the leaks, repaired the damage and gave the vaults a makeover.
Step 1: Sand Blasting
The render had been removed from the masonry by the client’s builder as Crown instructed.
We sand blasted the walls and ceiling to remove any foreign bodies and provide a good key for the tanking slurry.
The walls and ceiling were washed down with high pressure water spray to remove the grit and loose debris.
Step 2: Strengthening Fillets
There were many internal 90 degree corners including the wall and floor joints.
We applied a strengthening fillet along with any holes.
We repaired them with Koster Repair Mortar Plus.
Step 3: Resin Injection
The steel beam leaked over the door. We noted running water seeping out around the masonry.
We cut a groove in the masonry where the steel was in contact and drilled and inserted injection packers.
We pumped resin into the structure, displacing any water and filling the cracks and gaps, creating a waterproof joint. We repaired the groove with a Koster flexible seal.
Step 4: Slurry Application
We applied Koster NB1 to the masonry via a high pressure spray, to force the material deep into the cracks and cavities of the masonry.
This process also highlighted the defects in the masonry. We identified cracks and holes.
We fixed these with Koster Repair Mortar Plus and applied a second coat of Koster NB1 to the masonry.
Step 5: Slurry Elastic Application
We applied NB1 Elastic slurry via a high pressure spray with 5 coats.
In between coats, we used Koster Repair Mortar Plus to repair any seen defects, cracks or holes.
The NB1 elastic tanking slurry is flexible and will move with the structure, reducing the risk of failure due to movement.
Step 6: Lime Render Platered
We applied multiple coats of lime render to the tanking slurry.
This is a specialist pre-bagged hydrophobic render which is a water proofing material. The lime render has been skimmed with multi-finish plaster at the client’s request.
The works come with a lengthy Crown Preservation guarantee and an insurance backed GPI guarantee.