Cracks occur as buildings age. Temperature changes and weather conditions make them grow. They can be classified as structural or non-structural.
Structural Cracks:
Structural cracks, that are usually found in the load-bearing parts of the construction like beams and columns, are serious. They are caused by movements of the foundation, shrinking of masonry as it dries or heat-related roof shifting. They form in straight vertical or horizontal lines and or stepped diagonal lines. These cracks should be taken care of by specialists.
Non-structural cracks:
Non-structural cracks refer to cracks in the plaster of interior or exterior walls. They are mostly caused by reactions within plaster compounds and building materials, and external forces like temperature changes, environmental factors etc. They can also be caused by use of poor materials and inferior labour. They are usually haphazard and not very wide, and are found on the flat portions of the wall and not on the load bearing areas. They can be effectively treated using crack filling compounds. Make sure to fill the crack till the wall is level.
Most water-based crack fillers contain some amount of water along with other ingredients, so that it can be applied easily with a putty knife. Once the crack is filled in with the paste, the water may evaporate from it, causing it to depress a little. This is called shrinkage. The issue can be solved easily by applying multiple coats till the crack is fully filled and all shrinkage accounted for.
VOCs or Volatile Organic Compounds are substances within paint that give off harmful emissions. These emissions continue long after the paint has dried.They have a strong odour, and cause a variety of health problems such as headaches, dizziness, asthma, and allergies. They are also linked to cancer. Select a Low VOC finish so that your family and your children are not exposed to harm.
For paint to adhere well, to perform over time and display all its characteristics, the substrate must first be prepared properly. Surface dirt will prevent the paint film from adhering to the substrate and will peel off faster. If fungus is not removed, new growths could appear even on the newly painted film. Flaking paint will also reduce the new paints ability to adhere.
The smoother the surface, the better the finish and performance. Fill all holes and sand surfaces to create an even surface for the paint.
New generation paints have excellent washability characteristics. This means you can wipe them with mild detergent and water to remove stains, without affecting the colour or the finish of the paint. Most beverage, food and dirt stains, and some chemical patches can be removed in this manner. Washability characteristics differ from paint to paint so check the technical features to understand what performance you can expect.
Water-based finishes are usually odour free. Do keep windows and doors open while painting. However, a slight smell may linger for a few days if you’re using a solvent based paint.
Brush the affected area thoroughly with a wire brush. After the growth is removed, clean the surface with a bleaching powder solution made by mixing 50g bleaching powder in 1 litre of water. Apply on the affected area with a sponge, and leave the solution on overnight. After it dries, wipe it off with clean water. This will effectively remove the growth. However, if there’s dampness in the area, the growth may recur. Therefore it is a good idea to waterproof that entire area. Keep doors and windows open so that the area is exposed to air and sunlight.
First, ensure that all switches are off before you start removing the paint. If the paint splatters are recent, they can be cleaned with a cloth soaked in warm water. If they have already dried, scrape off with a paper cutter, after first wrapping its blade in a cloth to prevent scratches from forming. Do not use any strong solvent as it may damage the plastic surface of the panel. Do not switch on any fixtures till the board is dry. You can also use mineral turpentine oil to remove paint from glass and steel. Do note that the recommended method for painting involves proper masking of light fixtures and other elements in the house to avoid such problems.
Try to paint when temperatures are above 3 degree centigrade and relative humidity is less than 85%. For more details refer to the technical data sheet of your selected product.
Damp proofing is a system of control which prevents moisture from passing through walls and floors into interior spaces. It increases moisture resistance, but does not completely prevent water from entering the surface. Waterproofing is a more complete method of resisting moisture as it stops water seepage caused by hydrostatic pressure, which is the rising of ground water into your surfaces. Damp proofing uses materials like tar. Waterproofing is more environmentally friendly and uses materials like rubber.
Seepage and leakage are very similar and are often confused. Seepage is when water escapes from all over a porous surface, usually leading to damp patches. Leakage is when water or any liquid escapes through defined cracks or holes on a surface. It usually appears in the form of drips. Depending on whether the problem is leakage or seepage, the wall can be treated accordingly.
The most effective way to measure moisture within a substrate is to use a moisture meter. This is usually carried out by professionals. Moisture meters have LED displays which show the moisture content, usually in % MC. ASTM, the American regulating body, details 5 test methods. The plastic sheet method involves taping a clear plastic sheet to the surface and examining it for moisture after at least 16 hours. Other methods include using specialized in situ probes and infrared thermography.
Moisture causes blisters, where the paint lifts from the surface in little bubbles. It usually occurs when moisture seeps through exterior walls into the home, or through damp interior spaces like bathrooms, to the exterior surface. It can also happen if paint is applied on a damp surface. Check for sources of interior and exterior moisture, and deal with them by installing vents, exhaust fans or sidings as appropriate. Then, scrape away all loose paint and sand the surface. Repair old caulk. Once the surface is completely free of old coatings and fully dry, you may repaint with a high quality water-based paint.
Adhesives and sealants perform two different functions, though some of the properties are common. Adhesives are used to bind two materials together and prevent them from separating. Sealants are used to block gases and liquids from entering the surface on which it has been applied. Depending on the type of sealant, they have multiple functions; they keep out moisture, provide insulation, and protect against fire. Some sealants may have adhesive properties, and some adhesives may have sealing qualities. However, sealants are generally more elastic to stretch over a surface and have less strength than adhesives which must hold together two surfaces.
Movement Accommodation Factor (MAF) refers to the ability of a sealant to expand or contract to accommodate movements in the joint. It is expressed as a percentage of the joint’s minimum size. MAF is important because all materials change in size depending on the temperature.
Avoid wasting paint. Empty containers may also contain some residue of the paint, so they must be disposed of safely. Dispose of surplus and non-recyclable products via a licensed waste disposal contractor. Disposal of this product, solutions and any by-products should at all times comply with the requirements of environmental protection and waste disposal legislation and any regional local authority requirements. Avoid dispersal of spilled material and runoff and contact with soil, waterways, drains and sewers.
Store your paints in cool dry conditions. Ensure there is adequate ventilation during application. Wear overalls, goggles, dust masks and gloves and avoid all contact with skin and eyes.