Tanking & Waterproofing Services
Tanking and Waterproofing;
We have systems for use on both the negative and positive sides of the structure, basements, tunnels, shafts, culverts, tanks, sumps etc.
We first make sure that we have stopped any active leaks. Once this has been done we will clean and prepare the substrate to give the best surface profile to take the coating system. We have tanking systems that need primers and systems that need no primer.
If the substrate is too wet to be coated we have special indirect hot air dryers that generate large volumes of clean hot air and quickly dry the substrate to the point where the tanking system can be applied.
On internal surfaces to be coated we install a 45° fillet to all 90 corners using fast set natural cement or epoxy mastic. Once all the preparation has been completed (note, preparation is always the main part of any project and cannot be skimped) the coating system is installed, either spray applied or hand applied depending on the choice of material and the site constraints. After the coating has cured / dried enough to allow access the coated surfaces these are inspected for any holidays/voids/patching, and are then rectified, recoated if needed and the site cleaned down and signed off.
For externally applied tanking this usually involves coordinating with other contractors active on the site. We work with the other contractors, communicate our timings and site needs to enable the tanking to be installed and completed on time with minimal disruption to the site.
Power Coatings Ltd specialise in waterproofing all types of pits, shafts, lift & escalator pits. It doesn’t matter if they are constructed from concrete, brick, concrete blocks or metal lined pits! We can waterproof lift pits that are 100 years old, 50 years old or just 5 weeks old. We have tried and tested, proven solutions for them all.
Case Study: Four Seasons Health Care
The lift shaft had been suffering from water infiltration and flooding for approximately two years. This is a common problem in lift shafts. The problem was made worse due to structural defects within an adjacent drain. The water infiltration regularly reached a level of 500mm. The continual standing water caused corrosion to the substrate and a constant foul odour which permeated throughout the ground floor of the care home. The lift was situated next to the kitchen area which made the issue even more serious.
About The Project
It was first necessary to repair the structural defects. A dual process was then chosen to deal with the infiltration issues. We selected a combination of expanding polyurethane resins to stop and seal the infiltration and a 100% solid epoxy coating system was chosen to coat, renovate and strengthen the base and walls of the shaft. This particular high build epoxy was selected because of its speed and ease of application and also its independently tested ability to adhere to damp substrates, ensuring that the lift could be back in service as quickly as possible.
Prior to the epoxy application, the substrate was prepared, using standard techniques. The initial process was to high grit blast the chamber surfaces, leaving a good keyed substrate, which was ideal for the most effective application of the coating. Following the grit blasting, we injected an expanding polyurethane grout via non return packers through the wall at regular intervals to stop the infiltration of water. A fast set cement mix was applied to any remaining minor water leaks.. The final part of the preparation was to spray a dilute mild bleach wash to kill off any bacteriological growth followed by a light (Muriatic) acid etch to remove any sulphates/carbonates and other contamination.
The chamber was then sprayed with the high build plural component epoxy using Graco equipment, to a thickness of 3mm. Once the coating had cured and had been inspected the lift was then put straight back into service.
The epoxy chosen has a proven ability to adhere to damp surfaces and good resistance to negative water pressure to prevent infiltration, and also exfiltration made it an ideal choice for the lift shaft conditions. The coating will deliver a long-term refurbishment solution and a warranty was provided to the customer. Independent testing of the product’s chemical resistance and other attributes gave the customer confidence in specifying this method of refurbishment. In addition, the speed of application and short curing time ensured that the lift was off-line for a minimal time period.