My car porch concrete flat roof has crack and it is leaking, how do I fix it?

Fixing crack with Sikadur®-20 Crack Seal

  1. Slightly widen and increase the surface on the existing cracks.
  2. Remove dit and dust from the cracks.
  3. Mixing: Pour component A & B into the bottle with 1:1 composition.
  4. Shake it slowly for 15–20 times until uniformly mixed.
  5. Apply mixed material into cracks / caviies until full. wait till it dries.


Apply SikaCoat®-500 Super

  1. Mix SikaCoat®-500 Super manually or use a low speed mixer until it is completely homogeneous prior to application.
  2. Apply a generous base coat of SikaCoat®-500 Super using roller or brush.
  3. when touch dry, apply another layer of SikaCoat®-500 Super at different direction.
Can I mix skim coats with latex?

It is not advisable to mix skim coats with latex. Only add the amount of clean water recommended.

Can I apply skim coat on external walls?

Yes. There are skim coats specially formulated for external walls.

For assistance, please contact us.

How long must I wait before painting over skim coats?

Generally, painting works can be carried-out after the skim coat has dried, around 7–14 days, subject to site condition.

How long does it take for skim coats to dry?

On drywall, skim coat normally takes about 2–3 days to dry.
On concrete surfaces or plastered walls, skim coat takes about 5–7 days to dry.
In extreme situations such as high humidity and constantly damp substrates, skim coats may take more than 7 days to dry.

How long must I wait before skimming over new concrete or new plastered wall?

It is advisable to wait at least 14–21 days before skimming work can commence on new concrete or new plastered wall. This will allow sufficient time for the new concrete or new plastered wall to fully cure.

Can I plaster and/or skim over old surfaces?

Yes. The old surfaces must be structurally sound, level, solid and stable, and free from dusts, dirt, oil, grease, standing water, laitance, paints, curing compound and any material / coatings that reduces bond. If the substrate contains any of these contaminants they must be removed by grinding, water-jetting, or sanding.

All dusts, loose and friable material must be removed, preferably by brush and/or vacuum before plastering / skimming.

Can I skim on drywall (gypsum, cement, plaster boards)?

Yes. Use only acrylic skim coats.

Sika’s Product:

What are the differences between skim coats and plasters?

Skim coats are fine mortars, and they are applied to a thickness < 5 mm. The surface of the skimmed area is smooth.

Plasters, on the other hand, are coarse mortars and they are applied to a thickness from 5–30 mm. The plaster surface is constantly rough.

What are plasters?

Plasters are coarse mortar, applied onto concrete, brick and block walls to a thickness more than 5 mm to create a level surface. They are also used as a base layer before skim coat.

Sika’s Product:

What are skim coats?

Skim coats are fine mortars applied onto walls and ceilings to a thickness of 2–3 mm to create a flat, smooth and uniform surface, to be painted or re-textured. As a guide, you should apply at least two skim coat layers to achieve a smooth and consistent surface.

Sika’s Product:

What are the benefits of sealing grout joints? How do I seal grout joints?

Generally, most grout joints are filled with materials made from cement, making the filling material porous and absorbs liquid readily. Consequently, grime, water and moisture can seep through it and under the tile. After a prolong period, problems such as debonding of tiles and hollowness may occur.

Sealing grout joints will reduce/prevent the growths of mold and mildew. It also prolongs the tile lifespan and minimize damage to a considerable extent by keeping water and moisture out.

Before sealing grout joints, carry-out a simple test by releasing droplets of water onto the grout. If it absorbs water, it is a tell-tale sign that the grout joint needs sealing.

Normally, grout joint sealing materials comes in liquid form. To seal grout joints, apply 2–3 layers of the sealing material onto the tile grout.

Sika's product:

Can I mix tile grout with latex? Which latex should I use?

Yes, most cementitious tile grouts can be mixed with latex.

Sika's product:

What is epoxy tile grout?

Epoxy tile grouts are made of epoxy resins and filler powder which makes it waterproof and resistant to stains, harsher cleaning detergents and mild chemicals. Its durability makes it the ideal choice for wet areas (eg. showers, kitchens and bathrooms), swimming pools, high foot traffic areas and commercial areas.

Sika’s Product: Davcopoxy 271

What is sanded and unsanded tile grouts?

Sanded tile grouts contain sand and is used for grouting floor and wall grout joints, with width between 3–12 mm. The sand thickens the grout to prevent shrinkage and cracks in wider grout joints.

Unsanded tile grouts does not contain sand and is used for grouting grout joints that are ≤ 3 mm wide. It has a smooth texture making it suitable for grouting smaller joints.

Sika's product:

What is a tile grout?

Generally, there are two types of tile grout:

  1. cementitious tile grout – made of cement and filler powder
  2. epoxy tile grouts – made of epoxy resins and filler powder

The space in-between the tiles is called a “grout joint”. Tile grout is used for filling up grout joints in between tiles and natural stones and is available in a wide range of colours. It helps to keep dirt, debris and water from getting in between and under the tile. It also adds rigidity and strength to the tile installation besides keeping the tile line straight.

Sika’s Product:

  • Cementitious tile grout - Davcogrout
  • Epoxy tile grout - Davcopoxy 271
What tile adhesive shall I use outdoor?

For tiling outdoors, an improved cementitious adhesive with extended open time (C2E) or an improved deformable cementitious adhesive with extended open time (C2ES1) is recommended.

  • C2 Tensile adhesion ≥ 1.0 N/mm² (after normal curing, water immersion, heat aging and freeze-thaw cycles)
  • E Open time ≥ 30 minutes
  • S1 Transverse deformation ≥ 2.5 mm and < 5 mm

Sika's product:

How do I select the right tile adhesive?

In selecting tile adhesives, you need to take into consideration the

  • type of substrate - screeds, concrete, boards, over existing tiles, heated floors etc.
  • type of tile and size - ceramic, porcelain, stoneware, large format, mosaic tiles etc.
  • the environment - outdoors, indoors, floors, walls, shower wall, bathrooms, wet areas etc.

For assistance, please contact us.

What are tile adhesives?

Tile adhesives are specially formulated factory-made, ready to use adhesive with improved bonding and thixotropic properties. They are used as adhesive for laying/setting tiles (ceramic, porcelain, natural stones etc.) on walls and floors, both indoors and outdoors.

What are the differences between porcelain and ceramic tiles? Does this affect the type of tile adhesive I should use?

Porcelain tiles are more durable (denser and harder), has lower water absorption properties (≤ 0.5 %), and are normally used in areas with high volume of foot traffic (eg. commercial properties, hotels, offices, and retail outlets). Hence, porcelain tiles require a tile adhesive with improved bonding properties (C2).

Sika's product:

Ceramic tiles are easier to use (less brittle, easy to cut and shape), have higher water absorption properties (˃ 0.5 %), and are normally used for walls and floors in housing projects, interior walls of commercial buildings and low volume foot traffic areas. Therefore, ceramic tiles require a tile adhesive with normal bonding properties (C1).

Sika's product:


Should I use a primer before tiling?

Although the use of primers is not widely practiced in tiling most substrates, priming can improve the laying/setting of tiles by eliminating dust and stopping the substrate from absorbing all the water from tile adhesives, especially when the substrate is porous.

For assistance, please contact us.