Terrace Waterproofing
- Details
- Created on Friday, 09 May 2014 12:20
Types of terraces.
There are many types of terraces and waterproofing systems. First, we will consider the following terraces types:
- Impassable terraces.
- Passable terraces.
- Landscaped terraces.
- Impassable flat roofs.
- Expansion joints in terraces.
Impassable terraces.
An impassable terrace can be waterproofed with a lower level of demand and also the waterproofing professional has a wide range of products on the market to choose. Materials that can be applied: paints, tar paper, canvas, etc. The result specially depends on the skill and experience of the professional.
Passable terraces by people or vehicles.
A passable terrace by people or vehicles, has an extreme level of demand. The professional must have some previous experience and must use products that would resist the weight and treads of the vehicles.
Landscaped terraces.
We think they have a similar behavior as the pools. The professional should have a good knowledge about waterproofing, to do a good job.
Impassable flat roofs.
The impassable flat roofs are usually waterproofed with rubber fabric or PVC. Then, the canvas will be protected against solar radiation with materials such iron sheets, gravel, etc. This type of roof is easy to perform and does not usually cause problems if it has been done correctly.
Waterproof expansion joints.
To waterproof expansion joints on terraces, it is often a challenge that just a few professionals know how to resolve.
Waterproofing of terraces.
To waterproof expansion joints on terraces, it is often a challenge that just a few professionals know how to resolve.
For waterproofing is a professional experience needed. A professional with no experience using the best possible products, will always do it wrong. Making a successful leakproof test after applying the waterproofing treatment, is not a guarantee that the work has been well done.
Formation of salt deposits.
Salt deposits sometimes can be found on downspouts, sinks and walls.
The origin of the problem is based in the precipitation of carbonates in the drainage of water from the terraces within the chemical principle explained below:
An aqueous carbon dioxide solution, has the properties of a weak acid. Carbonic acid, has not been isolated as such. Its existence in the chemical solution is inferred from the fact that it forms salts with the alkalis.
The acid is diprotic (K1 = 4.45. 10E 7 and K2 = 4.69. 10E 10) and forms two series of salts, carbonates and bicarbonates. Carbonates and bicarbonates of alkali metal and ammonium salts are soluble. The carbonates of other metals are insoluble and they can be precipitated by adding a soluble carbonate into its salt solutions.
Some metal carbonates, although they are water insoluble, are soluble in solutions of carbonic acid to form soluble bicarbonates. The formation of stalactites and stalagmites happens due the transformation of calcium bicarbonate (soluble) into calcium carbonate (insoluble).
The concrete type Portland grade 42.5, has in its composition 65% of calcium oxide, 4% magnesium oxide and 5% aluminum oxide, associated as silicates and aluminates. The hydrolysis of the mortar due capillarity with rainwater originates salt formation mostly soluble calcium bicarbonate, which in contact with the air, takes form into insoluble carbonate salt type, precipitating on drainpipes, sinks and walls.
The following pictures reflect this problem and normally the ultimate solution is to remake the waterproofing again as the drains do not exist or they are wrong. The pictures of the downspouts are salts formed in the last three years and the ones on the facade, in the last four years. In addition to the terrace waterproofing, it is necessary to make a proper drainage to prevent the formation of salt deposits in drains, downspouts and facades.
