Our client asked us to design and install a tanking system for the retaining walls of their Sheffield basement. We proposed a Type A and Type C combined system.
- Type A: Barrier Protection – internal waterproofing
- Type C: Drained Protection – internal waterproofing
The basement was to be used as habitable space so our specification included Fibran XPS 500-C insulation board. This product provides protection, insulation and drainage.
We installed Newton Fibran XPS 500-C below the Newton flooring membrane as a fully drained supporting spacer.
Fibran is an insulation board made from rigid extruded polystyrene foam. It forms a 50mm insulated spacer adjacent to the drainage channels which form part of the Newton Cavity Drainage Membrane (CDM) System. They are ideal as a fully drained supporting spacer below a floor drainage membrane. They also serve as protection for Newton’s liquid waterproofing membranes applied externally to earth retaining structures.
Main benefits:
It has the following excellent thermal insulation characteristics:
- It is a closed cell structure and as such affords extremely high resistance to water absorption
- It can withstand permanent submersion in water
- Fully inert when subjected to climate variations
- It has a high mechanical and compressive strength
- 100% recyclable
- Fully rot proof and does not develop mould
- Is of no nutritional value for rodents or insects
- Is resistant to acids and alkaline
It is our insulation product of choice when we are waterproofing because of its versatility:
- Serves as a spacer below the floor membrane
- It protects externally applied Type A waterproofing membranes
- It provides insulated support below Hydrobond 403 Plus waterproofing membrane
- Can be used for parking decks and green roofs
- Excellent for insulating below ground structures situated permanently within the water table.
Elsewhere on the project the combined waterproofing system was applied as follows:
Ground Floor
Internal: Type A (Barrier) Protection:
Type A waterproofing ‘barrier’ system applied to the internal block work structure.
- Blockwork treated with a lime inhibitor to limit the leaching of free-lime from the structure.
- Installation of fillet seals at the base of the bund using repair mortar. The use of fillet seals helps to ensure a smooth transition between horizontal and vertical surfaces that will minimise the risk of leaving gaps or holes unsealed during the waterproofing works.
- Application of two coats of Newton Hydrocoat 105 1K Tanking Slurry waterproof membrane coatings to the internal surfaces. Walls first visit/Floor second visit.
Internal: Type C (Drained) protection:
Secondary protection, which manages any water ingress which occurs as a consequence of an installation defect, was provided by a cavity drain membrane system.
Wall Cavity Drain Membranes
Walls: We mechanically fixed 8mm membrane to the internal side of the external cavity to be taped into the wide DPC.
