With more than 10 years of working experience in Hong Kong, we have a comprehensive knowledge about waterproofing works for all the buildings, justifying the cost-effectiveness of the usage of materials and evidencing the practical application of the advanced technology.

We would like to share our knowledge and experience with you and appreciate your comment.

General Waterproofing Concept

As a consequence of new building development and enhancement of consciousness of building maintenance, waterproofing works should be an indispensable consideration indeed.  In the course of undertaking waterproofing works, workmanship and choice of materials is a key element.  We usually consider the waterproofing materials in respect of adherence, durability, application convenience, price competitiveness etc..

Common waterproofing works is cited as follows:-

It is the most effective for waterproofing materials to be attached on the structural concrete.    Taking polyurethane PU as an example, we require excellent adherence to substrate, good workability in application, great flexibility after cured, invulnerability to aging.  However, in view of cost concerns for maintenance works, surface application requires tougher strength and UV resistance to prevent the whole flat from damage even a pin-point punch to the waterproofing membrane.

Cracks and honey comb is very common in concrete formation.  Concrete crack is repaired by direct epoxy injection with mechanical pump while honey comb is repaired by waterproofing cement or direct application of epoxy coating on the surface.

Seepage often occurs as a result of frequent movement of expansion joint or aging joint sealant.  Beside simply replacement of joint sealant, we still have to investigate if there is structural expansion joint underneath. 

It is usually the result of damage of waterproofing system which leads to corrosion of reinforcement steel bars and spalling concrete eventually.  Before the waterproofing system is repaired, cement with strengthening additive should be used for repairing the damaged concrete area.

It is usually the water leakage in basement, lift shaft, water tank, podium etc.  Waterproofing materials are usually water-based with its characteristic application in wet surface.

Common Waterproofing Materials are quoted as follows:

1.      Polyurethane PU seamless waterproofing membrane for application of large and flat area.

2.      Epoxy is a two parts component which is mixed together for coating on concrete surface or injected into cracks with a mechanical pump.  The strength of epoxy can reach nearly 5 times of that of concrete.

3.      Joint sealant is usually applied on the surface of the structural expansion joint.

4.      Waterproofing cement can be applied on a large concrete surface.  Its unique property is capable of penetrating in concrete inside through the path of capillary tube action and block up the tinny void of concrete by chemical reaction.

5.      Cement strengthening additive is used to improve normal cement in respect of waterproofing, mechanical, resistant to chemical properties etc.  To a certain extent, it can be also used to repair concrete.

6.      High polymer waterproofing membrane is very flexible after cured and adhesive to cement, tiles, asphalt, metal and glass surface. Various colors are available.  Besides, there is a wide variety of waterproofing external wall paint.

7.      Water-reacting resin is injected from the path of leaking water and forms rigid foam to block up the leaking point.

8.      Quick-dry cement additive is mixed with normal cement and cured within a couple of ten second to block up the source of leaking.  After that, other waterproofing material is applied for strengthening waterproofing effect.

9.      Transparent waterproofing coating for application on external wall for sake of simple waterproofing effect.

There are many kinds of waterproofing materials for different usages.  A combination of usages is likely possible according to different site conditions.

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