Application of both sheet and liquid waterproofing membrane on flat roofs, decks, retaining walls, planter boxes and balconies. Internal wet areas (bathrooms, laundries etc), basement walls. Caulking, joint sealing. Epoxy Flooring. Leak detection and rectification. Wet basement and car park problems.
Sydney NSW Australia
- Align Constructions
- Carfax Commercial Constructions
- Dillon Building
- Jakin Construction Group
- KA Short Enterprises
- Plan Pacific Projects
- QRC Constructions
- Rozzi Constructions
- Sun Greenaway Builders
- Waves Building Services
Sheet waterproofing membrane: As the name implies, these are waterproofing membrane membranes that arrive at the site in the form of rolls. These are then unfurled and laid in an area. The most common type of sheet based membrane is a bituminous waterproofing membrane. This type of waterproofing membrane is stuck to the substrate with its molten part of bituminous using blowtorches.
Joints between adjacent membranes are also made with the same molten bituminous. The sheets are overlapped by about 100mm (4″) to form a waterproof joint.
With this type of membrane, joints between sheets are critical, and must be done perfectly to avoid leakage.
Other types of sheet based membranes are PVC membranes and composite membranes. The latter have a fabric base that provides strength and tear resistance, and a chemical that coats the fabric to provide resistance.
Since these membranes are factory-produced excepting the joints, they are consistent in quality.
Liquid membrane: Liquid applied membranes come to the site in liquid form, which are then either sprayed or brush-applied on the surface. The liquid cures in the air to form a seamless, joint-free membrane. The thickness can be controlled by applying more of the liquid chemical per unit area.
Since the application procedure is very quick, a contractor will try and finish the entire area to be waterproofed in a single day to avoid cold joints. However, if a very large area is to be done on successive days, cold joints can easily be done by overlapping the new membrane over the old – the chemical will stick to itself readily.
The membrane can tear or break if it is too thin. The adhesion of the membrane to concrete must be good.
If a concrete screed (layer) is to be applied over a waterproofing membrane, the membrane is made rough by sand broadcasting. This is throwing a thin layer of sand by hand over the wet membrane (before it has set fully) so that the sand sticks to the membrane and provides a rough surface the concrete can adhere toTypes
The type of waterproofing membrane chosen dictates how the waterproofing material will be applied to the structure. Each type of material and structure has its own specific application requirements. It is important to understand how each system works and the proper application.
Applied or liquid membrane – Spray applied membranes, cold-fluid-applied membranes, and hot-applied membranes are types of membranes applied by melting and then fusing a rubber, bitumen, or elastomer layer onto the surface to be waterproofed. Liquid membranes have grown in popularity for horizontal applications. Polyurethane elastomers are the most common material composition for a fluid-applied elastomer membrane. However, bitumen and other epoxy-modified spray-applied membranes are also available. The temperature at the time of curing is very important because temperature-based applications are highly sensitive major temperature fluctuations which could cause the membrane to seal incorrectly. Liquid membranes are not removable or repositionable.
Cold-fluid-applied membranes are brushed, rolled, or sprayed onto the surface to be protected. The liquid membrane dries or cures into a permanent waterproof membrane.
Hot-applied systems should include a thermometer so the temperature can be monitored throughout the process. The temperature must be kept within 25 degrees of the required application temperature to ensure even application.
Film or sheet membrane – Sheet, self-adhering sheet, sheet metal membrane, and sheet metal waterproofing membranes fall into this category. Film or sheet membrane are attached to a surface using adhesives, mortar, tape, straps, anchors, plastic welding, or fasteners. Membrane sheets can consists of bentonite clay, modified bitumen, rubber, polyethylene, polypropylene, ethylenepropylenediene monomer (EPDM), reinforced polymers, and other rubber and plastic sheet compositions.
Self-adhering membranes, also known as “peel and stick” membranes, have an integral layer of adhesives, so adhesives do not need to be applied to the surface of membrane at the work site. The release liner is peeled off the adhesive coating and the membrane stuck onto surface at the construction site.
Some non-adhesive sheet membranes can be removed and repositioned. PVC sheet and polyurethane rubber sheets are common material compositions. The seams or joints between PVC thermoplasticwaterproofing sheets can be welded, which is an advantage over thermoset, urethane rubber-sheet membranes.