Why choose liquid cold applied membranes?

Why Seamless, Low thickness  Waterproofing?        

Construction companies, particularly those that specialise in the roofing trade, face a significant challenge in finding an economic, timesaving, and durable waterproofing system for flat roofs. Roofs, whether they be flat or inclined, are subject to a lot of rain (and, occasionally, snow), and for any flat roof, this is a problem for the simple reason that water often collects and then stagnates on the roof surface.

Water resistance, UV resistance, acid rain resistance, and the ability to resist damage on thermal cycling are the main factor that determine the exterior durability of a particular roof coatings.  The above conditions are extremely detrimental for coatings that are used on flat (or low slope) roofs, and this is due simply to the very common formation of ponds on the flat roof! Furthermore, particular problems are presented by roofs with complex shapes, and a large number of breakthroughs, such as air-conditioning units, pipe supports, antennas, solar heaters, etc.

Recent decades have seen the waterproofing industry turn to new technologies, based on high technology synthetic membranes and liquid membranes. This new school of thought has abandoned the idea that only with multi-layer systems, are you guaranteed water-tightness. They are based on state of the art polymers (modified bitumen, PVC, EPDM, Hypalon, Polyurethane) of which, thicknesses of 2mm maximum, provide long term waterproofing and protection. Furthermore, being synthetic materials, they are produced under strict quality guidelines and standards, hence a consistent and reproducible quality is guaranteed.

Polyurethane liquid membranes combine the low thickness application along with the formation of a completely seamless membrane, no matter how complex a roof may be.

Polyurethane Liquid Membranes - The Seamless Waterproofing

The polyurethane system is applied in liquid form and cures to yield a seamless membrane with long-term flexibility. It is easy to seal around even the most complex fittings!  The liquid polyurethane system is actually easy and economical to apply, no matter what roof it is applied on:

  • 2 mm coating thickness applied in 2-3 coats.
  • Application on lightweight decks is not a problem!
  • UV resistant - no additional paint over necessary!
  • Easy to repair - local repair capability!
  • Long term maintenance is quick and low cost! Absolutely no need to remove pre-existing membrane.
  • May be applied on top of existing waterproofing systems!

After spelling out so many wonderful attributes, you may be wondering what the catch is?

Simply choosing the right Polyurethane system!

In order to have successful waterproofing, a polyurethane liquid membrane must be:

  • Impermeable - The membrane must be impermeable to prevent the passage of water.
  • Flexible - membranes need to withstand any normal movement that may occur in building structures.
  • Durable - The membrane must be able to retain its integrity over a long period of time.
  • Breathable - (In cases where this is essential). The membrane must be able to breathe so that moisture vapours from building interior and substrates can escape freely.
  • Humidity Barrier - (In cases where this is required) Detrimental in hot and humid climates.
  • Resistant - The membrane must withstand environmental and climatic conditions

Not all polyurethanes on the market satisfy these criteria!

A good Polyurethane coating will display:

  • Low water swelling rate and high retention of tensile strength; hardness and elastic recovery under prolonged exposure to harsh climatic conditions (UV, water, heat, ozone, etc.)
  • Constant adhesion to substrate when periodically exposed to harsh climatic conditions.
  • Superior performance in an environment of combined water, UV, heat, and all the aforementioned climatic conditions.

Alchimica offers a wide range of Polyurethane Liquid Membranes that fulfil the above requirements.  We have developed products that will suit every individual roof waterproofing need.  The waterproofing products available from Alchimica are tailor-made to provide long term protection against all natural elements. When a solution is needed for providing waterproofing below grade walls, foundations, highways, bridges, or just some simple, under-tile, roof waterproofing of domestic residences, Alchimica products will provide the ideal solution.

Alchimica Building Chemicals