House Construction from conception to completion – II

After learning about the binding material, cement, let’s move ahead towards the other important construction ingredients.

SAND:

Together with cement, sand is another important material in preparation of mortars and concrete. It is therefore important to understand the quality check parameters of this ingredient. The right quality of sand is significant in the durability and performance of the concrete/mortar mixture.

The ideal sand:

Generally, the river sand is considered ideal for construction. However, the practice being environmentally unsafe, companies avoid using river sand and prefer filter sand and manufactured sand over it.

Features of good quality sand:

  • Clear, angular and hard
  • Free from clay, mica, and soft, flaky material
  • Graded – mix of fine, medium and coarse sand
  • Free from contaminants
  • Moisture content should not exceed 7%

Selecting the right sand:

Filter sand is treated to make it better by washing off all the dust particles with water. The different consistency of sand is used for different purposes. For RCC slabs, rough sand can be used whereas for plastering work, it is advisable to use fine sand. Generally, sand should not be sticky when held in hand.

Manufactured sand:

The government is promoting the use of manufactured sand, also known as M-sand,  as it is a cheaper alternative to natural sand. Moreover, construction experts vouch that manufactured sand is superior in many ways. It is observed that mortars and concrete made using M-sand as a fine aggregate are superior as compared to natural sand mixtures. Therefor ready-mix concrete manufacturers are using manufactured sand for better quality product.

Advantages of manufactured sand:

  • No clay content
  • Scientifically graded to comply BIS specifications
  • Consistent quality is assured by customizing different grades as required
  • Cost effective

Sand being a significantly important material in construction work must be chosen and used with proper knowledge.

House Construction from conception to completion – I

“Whatever good things we build end up building us.” – Jim Rohn.

A building is much more than the individual parts that go into it. A quality home allows people to be in the comfort of knowing that their abode is made especially for them, and their needs. The quality of your home, to a large extent, determines the quality of the life of people dwelling in it. And hence, it is important to understand what goes into the construction of your house.

People constructing houses can never be sure of the quality of the materials that the contractor brings to site which eventually impacts the overall construction considerably. The most important structural components of a building construction are the columns-beams-slabs made of concrete and the walls which are made of bricks and plaster.

To help you understand the process from conception to completion, German Plast brings to you another series of articles on the features of the good quality building materials.

CEMENT:

Cement is the binding agent that holds the other ingredients together and therefore plays the most important role in providing strength and durability to any structure. It is used to make concrete for slabs, foundations, beams, columns, and mortar for brickwork, plastering, and flooring.

Types of Cement used in house construction:

  • Ordinary Portland cement (OPC) which is a combination of clinker and gypsum.
  • Portland Slag Cement (PSC) which is a combination of good quality blast furnace slag with clinker and gypsum.
  • Portland Pozzolana Cement (PPC) which is a combination of fly-ash with clinker and gypsum.

Although the blended cement like PSC and PPC take more time to set, they are considered the best cement for house construction. The final strength after 28 days is much more.

Intrinsically, it is difficult to decide upon the quality of any cement since the process of manufacturing is more or less the same for the most. However, there are certain features which distinguish a good quality of cement from the average one.

Features of good quality cement:

  • Reduced water requirement.
  • Improved workability.
  • Less permeable to moisture.
  • Improved resistance to acids and chlorides.
  • The reduced heat of hydration.
  • Easier to finish.
  • Reduced shrinkage.
  • Reduced leaching problems because it is low on free lime.

The color of cement has no relation to the strength characteristics. There is a common myth that darker color cement gives better strength. On the contrary, workers tend to add more sand in the darker color cement than the prescribed ratio which affects the mortar consistency and can cause problems.

The right way of using cement in construction:

Cement must be added to the concrete and mortar in a precise, consistent manner. Too little or too much cement in concrete and improper water-cement ratios results in lower strengths, shorter design life, and lower durability.

Selecting the right cement:

Cement accounts for around 12 to 18% of the total construction cost. Well established brands of cement offer quality, consistency, and durability and also greater strength characteristics. Hence, it is important to use good quality cement.

Cement being the most important ingredient; it is always desirable to use the best cement in constructions. Therefore, the properties of good cement must be considered and examined. Suitable tests can also be performed to ensure the quality of the cement.

Let’s paint the house beautiful!

Painting is a quick and cheap way to give a makeover to your house. A good paint job can enhance the beauty and add a protective layer, too. For durability and looks, repair and repaint as soon as you notice the crack, blister, or peel on your walls. As ignoring these problems will lead to a much more extensive—and expensive— job.

There are few painting tips every homeowner should know, regardless of he doing the paint job himself or hiring an expert.

Selecting the paint

Paint comes in wide varieties – sheen, matt, oil, latex etc. Out of which, latex is the most common and preferred paint type used due to easy maintenance and durability. It is more fade resistant and breathes better than oil, resulting in less blistering of the paint.

However, oil-based paint is ideal for preparing wood edgings, as it tends to cover marks and knots from the wood better.

Sheen or no sheen

Sheen or glossy paints have their own advantages depending on the purpose of deciding the paint.

  • Glossier paints are easier to clean. It is ideal for kids’ rooms, playroom, kitchen etc., which tends to get dirtier easily.
  • Semi-gloss is a good option for kitchens and bathrooms allowing easy cleaning and giving lesser shine.
  • Satin sheens have a satiny smooth finish which makes it a fit for kitchens, bathrooms, and lobbies.

Flat or matte paint is perfect for walls with lots of imperfections. The drawback of this paint type is that it gets dirty easily and is difficult to clean. It is a good choice for private rooms that do not get a lot of visitors.

Choosing the color

You can change the feel of any room in your house with a little designing and some color, vary the shades for a certain look or feel. A good rule of thumb is to remember the color wheel.

  • A white or an off-white color gives the rooms a brighter and clean appearance.
  • Colors near each other on the color wheel such as blue and purple are analogous to each other and will allow one color to stand out more.
  • Colors opposite each other on the color wheel such as green and red are complementary to one another and will nicely play off each other.
  • Staying within the same shade of color will give you a subtle and soothing look.
  • Painting with cool colors such as blues, greens and purples make small rooms appear larger and airier while colors such as reds, yellows, and oranges will give a room a more vibrant appearance.
  • You can vary the warmth even with a red or yellow by choosing muted shades of those colors such as pink, peach or a buttery yellow.
  • Warm colors have cool ones as their complementary colors while cool colors have warm compliments.

Painting the ceilings

Change the entire getup and visual size of any room by applying little creativity in painting the ceilings.

  • Lower a high ceiling visually by painting it a darker shade than the walls.
  • Expand a room by selecting a lighter color for your ceiling than the walls.
  • Add a tint of color to your ceiling paint for a tied in and subtle looks.
  • Paint the ceiling, door trim, and floor moldings the same shade such as a creamy ivory to add a touch of elegance and a nice transition throughout the room.

Creating Focal Points

Focal points are important when painting a room. Add a darker color to one particular wall and change the entire look of any room.

  • Make a large room look smaller by painting one wall a darker shade.
  • Highlight any interesting aspect in your rooms with a darker, complementary shade to the one you have chosen for your walls.
  • Visible stairways, especially those in the middle of the room look incredible when painted a darker shade than the walls and gives you a wonderful focal point.

With a little paint and some creative imagination, you can save lot money spent on interior designing of your house. Change the entire look and feel of your house and make it stand out.

Home Care During Monsoons

Monsoons are certainly one of the most exciting seasons of the year. The beautiful experience of sitting on the balcony of your house and watching the raindrops is truly mesmerizing.

 

However, the season also brings the odds of damaging to your den. Leakage, cracks, rust, fungus, and dampness are some of the few diseases that your home becomes vulnerable to. And, one of the worst affected, are the walls of your house.

 

German Plast brings to you, the tips and tricks to prevent the damage to the walls when it is pouring outside.

 

Protecting the exterior walls of your home

The quality of paint used on the exterior of a house plays an important role in protecting the walls. The inferior quality paint allows moisture seepage which gets collected within the walls. This built-up moisture creates damp patches along the interior wall surfaces resulting in shedding of the wall paint.

 

Once the moisture gets collected within walls, it remains there even after the monsoon season so, the walls repainted afterward, remain prone to the damage.

 

To protect the walls from damage, a coat of waterproof cement paint is highly recommended much prior to the setting in of the monsoons. A coat of damp proofer can be applied to the exterior of your house as a decorative as well as waterproof paint.

Protecting the interior of your home

Ensure cross-ventilation to keep the humidity level in check and reduce the effect of dampness.

Even the damage is already been done and the walls are peeling due to dampness, there are still ways to reverse the effect.

  • Fill and seal the cracks with modified waterproof mortar.
  • Use the same polymer to seal the joints in the pipes that carry the rain water.
  • Replace the damaged wall tiles, if any, to prevent water seeping.
  • Open the structural cracks in a ‘V’ shape and fill with crack fill-putty before painting the walls.
  • Ensure there is no loose plaster by tapping on the walls. (A hollow sound is an indicator of loose plaster.)
  • Ensure proper curing time post the repair work to bridge the cracks during re-plastering.
  • Make the surface dry and free from dust by scraping with sandpaper.
  • Fungus-affected areas need separate bleach powder treatment.

 

So, the next time you are planning to get your walls painted makes sure you do it before the monsoon. Moreover, opt for the specialized paint with high water repellency that is modified with silicon. You will enjoy the season without the worries.

Strong construction happens only with the right ingredients – II

While we learnt about cement as an important component of concrete mixture, let us now understand concrete and an important part of construction work.

Concrete

Concrete is a mixture of cement, water, sand and broken stones in a definite proportion which is a workable mass initially and hardens over a period of time. The concrete is normally recognized by its strength which is the compressive stress required to make a 150mm x 150mm x 150mm cube crack.

The process of making and using cement concrete is covered by BIS guidelines. The making of concrete to get specific properties (like strength, for specific type of work etc.) is called concrete mix proportioning. The strength of concrete is influenced by the quality, strength and other properties of the ingredients in concrete like sand, jelly or crushed stones and cement.

Ingredients

Cement

Cement bags with ISI mark with a number below indicate what type of cement you are using. The quality reduces with time. However, if it is stored in well-protected rooms, it can be used up to 60 days, but cement beyond 90 days from manufacture is not recommended.

Sand

Sand should be clean river sand or manufactured sand. Silt content in sand is very harmful for the concrete or mortar. The filter sand supplied in big cities is also not recommended.

Stones

Course aggregates or crushed stones provide the mass and strength to the concrete mass. We should have a mix of all sizes of stone pieces below the specified size so that small pieces sit in between big pieces and give concrete a good mass.

Water

Water is the life of concrete and until cement comes in contact with it, the mortar many not achieve any binding property. However, excess water would dilute the binding property and affect its strength. This is referred to as water-cement ratio by engineers. A lower water-to-cement ratio gives better strength.

Admixtures, available as plasticizers, can be used only with advice taken from the technical team of the cement manufacturer or the admixture manufacturer.

Points to remember:

  • For procedures like curing, vibrating or compacting of concrete, one has to ensure that there are no leakages in the form work.
  • It is better to keep concrete moist all along – start spraying water on concrete from about three or five hours of concreting. This reduces the appearance of hairline cracks.
  • The curing should continue for about 28 days in concrete and 12 to 15 days for plaster and mortars.

Strong construction happens only with the right ingredients – I

The journey of building a home is exasperating. The unorganized construction industry has no fixed regulations except for few guidelines of building bye-laws to manage the work. However, there are few guidelines provided by the Bureau of Indian Standards (BIS) regarding the quality of the materials used and the rules to be followed in the construction practice.

This series of articles is a small effort to educate you in knowing the components that go into the construction work.

Cement

Cement is one of the basic construction materials manufactured in controlled conditions. There are two types of cement for which Bureau of Indian Standards (BIS) has drawn up specifications that can be used in normal construction work.

There is a perception that blended cement is not good for construction. On the contrary, blended cement is much better for plastering and masonry work. The blended one is made by mixing industrial bye-products. The mortar and concrete made of these cements have better durability and chemical resistance. In fact many underground structures are built with slag cement or the concrete is mixed with GGBS.

Important tips

  • Cement color comes from the raw materials used in the manufacture. It is not an indicator of strength or any other of its quality parameters.
  • Technically cement is something like glue or gum when it is mixed with water (cement-water reaction produces a gel called CSH gel). Addition of more water to cement would dilute the CSH gel and make it weak.
  • Cement requires a specific amount of water to complete the chemical reaction; any excess water will not participate in the chemical reaction but remains in the mass as water.
  • Use of less cement in any work will produce less gel, hence less binding, and addition of more cement may not help much.
  • Use of blended cement will give you better results as the blending materials are slow in reacting, hence they would be releasing the CSH gel slowly over a period of time. It has been observed that if this period is as long as 90 days or even a year, it would strengthen the concrete or mortar better. It is also called secondary strengthening.
  • The chemical reaction of cement is irreversible; hence it is advised to take proper guidance from your engineers or from the technical help given by the cement manufacturer.

Read our next blog post to know about concrete and its specifications.

Add a “WOW” factor to your room

We all have some desires for our dream house. While, having a beautiful and captivating interior is one thing, but a crafty modern design, sustainability, and integration with natural elements is also of absolute importance.

To have the former features is a matter of taste but the later ones are the part of basic home-building engineering. Once a strong, durable and living-friendly structure is set in place, then comes the time to add that extra “wow” factor to your dream home.

If you are one of those who like to experiment and is not reluctant to try of different themes, then read on to inculcate some cool and different ideas to decorate your home.

How to dress a room to impress?

A little wallpaper, paint, and or colorful accents could make such a big difference in your home. Here are a few ideas of home decor to make your dream home unique.

COLOUR AND WALLPAPER

Dark colors can create exciting interiors with a palette of greys, blues and blacks. However, bright colors have its own charm and can add a different life factor in our interior design. If you don’t fancy using paint but want to bring in pattern as well then there is a wonderful choice of wallpapers which will make your heart beat a little faster.

STATEMENT ART AND PICTURE WALLS

Oversize and emotive art piece is an instant turn-up to create an impact in a room. Choose a single large image or create a gallery wall with lots of different images. You don’t have to break the bank to create this look either. You can go down to your local art shop, buy a canvas and a few paints and let the creative juices flow.

STATEMENT LIGHTING

This is an easiest and the perfect, way to take your room from good to extraordinary. Invest in a statement light like a stunning glass chandelier which can really pop against the dark walls. Another alternative is to invest in a piece of neon art for the walls which will combine statement walls with statement lighting.

RULES KILL CREATIVITY

When the rules are challenged, or even broken, wonderful things can happen especially when our end result is to create drama. Put things in unexpected places like wallpaper in the bathroom. People don’t usually expect to see it there. Put a canvas painting among the crockery on your kitchen shelves or mix some traditional pieces with a modern setting.

EMBRACE METALLICS

The natural glow and reflective quality of metallic add glamour and sparkle to any room. For a quicker, and more affordable, try highlighting features with metallic paint or invest in some shiny gold home accessories.
The bottom-line is – be brave, be bold and show off!

A perfect plastering finish

In construction, I observed people often complain to contractors about poor quality of work execution. Not to surprise, contractors are only responsible because they could not carry out finishing work properly.

We know, people who hire construction experts to execute their work because they are unable to do so. In most of the cases Home owners have not much knowledge to check the work quality therefore they only can examine building finishing. Also, they cannot understand how to check quality of RCC, PCC or brick wall. Generally, people well thought-out finish of their house or offices should not be ugly and it is only mistake construction people do just not delivering quality plastering work.

Plastering itself an art and require quality execution, any error left during plastering work can ruin your hard work and may leave neighbors to laugh. Things should be taken care during plaster work may help you to prevent micro cracking and uneven plaster surface.

Minimize plaster thickness to prevent cracks

Plastering thickness should be kept least possible just to cover up the rough surface. Minimum thickness of 12 mm and 6 mm are ideal for wall and ceiling respectively. If you required more than 15 mm thickness then plastering work should be applied in two coats.

Greater Plastering thickness causes cracks and tendency to fall down in pieces over period of time.

Simple Fundamental of surface plastering

Plaster is layer of cement-sand mix which acts as damp proof course. It enhances the appearance of building and provides sound and thermal insulation. Ratio of 1:5 cement-sand for exterior surface and 1:3 or 1:4 considered ideal for internal surface.

Surface should be wet before applying plaster and it should be started from top to bottom towards floor.

Get smooth finish for interior and rough for exterior

For great interior painting finish, plastering work should be even and smooth. Internal wall and ceiling plaster smoothness can be achieved by applying neat punning cement after plastering the surface.

Exterior wall plaster should be more or less uneven to prevent rain water penetration. Also, it gives pleasant appearance as smooth surface allow visualizing defects.

Common mistake should avoid during plaster

Wire mesh needs to be fixed for RCC and masonry joints prior to apply plastering the surface.
Window and door opening plaster edges should not be sharp and slope of window sill bottom plastering projected towards external face of wall to avoid entering water in rain.
Door and window opening plaster should be well in plumb to avoid gap between frame and surface.
Curing of plastering work should be carried out for at least 14 days.
Wall painting work should not be carried out until it gets completely dry.
Margin for door and window frame equal to plaster thickness should be left out.
Concealed electrical wiring and connection job should be finished before plastering.
If you adhere to technical guidelines for plastering work definitely it will enhance wall appearance and offer firm and smooth base to paint your wall.

Sustainability Of Concrete

Sustainability is an ill-defined and vague concept in the construction industry. There are few tools or even metrics available to help decision makers specify one construction material over another in relation to sustainability. One reason for this is the sustainability of concrete, the most widely used material in the world, is still a difficult concept to quantify.

Most sustainability or green voluntary certification programs attempting to qualify sustainable materials have focused primarily on energy, material and water conservation; indoor environmental quality; and site selection and development. While these are all important aspects of sustainable building design and construction, lifecycle does not appear to be an integral part of this definition.

Quantifying sustainability

When selecting a building material, sustainability should be easily quantifiable. One method for assessing the sustainability of a construction material could be to divide its LIFECYCLE by the amount of non-renewable RESOURCES required in its manufacturing process.

“Lifecycle” refers to the durability of concrete, in years. It is linked to fatigue life and other material properties such as shrinkage, cracking, and porosity.

“Resources” refers to the quantity of non-renewable resources used in concrete manufacturing (such as, but not limited to, carbon footprint).

German Plast plays an important role in improving the sustainability of a construction, mostly because its chemistry and materials science differs from the well-established standards of portland cement. It can play a significant role in the sustainability of concrete technology from the perspective of raw materials use, energy demand, carbon footprint, and pavement longevity.

How to concrete in hot weather

As we read in the earlier blog post, Hot Weather Concreting can affect the strength of a structure. It is therefore important to know what precautions we can take to avoid the ill-effects of concreting during hot and arid weather.

The first immediate solution for concreting in arid and hot weather /low humid regions is to pour concrete during early morning or late evening. This may mitigate the bad effects to a large extent. In case, if the concreting pour has to be done during the day, other precautionary measures could be undertaken for better results.

  • Lower the temperature of the concrete ingredients before they are used for concrete mixing.
  • High early strength cements to be avoided unless the initial high strength of concrete is required at the site
  • Aggregates may be protected from direct rays of the sun during concrete production by providing shades over the stockpiles.
  • Sprinkling the stockpiles of coarse aggregates with water and keeping them moist is another option to be considered.

The only precaution to be taken care is not to flood them so as to affect the moisture content considered during concrete mix design.

The mixing water has the greatest effect on the temperature of concrete since it has a specific heat of about 4 to 4.5 times that of cement or aggregate. Hence chilled water or ice is preferred during concreting at high temperatures. If at all ice is added to the mixing plant directly, it is added in the crushed state only and complete melting is to be ensured before mixing of concrete ingredients is complete.

Use of chemical admixtures like water reducers/retarders helps in delaying the setting of concrete. However, use of these chemical admixtures needs to be carefully done as per manufacturer’s specifications and expert engineer’s advice.

Also, need to plan adequate manpower and machinery to complete the concrete pour at the shortest time possible during hot weather.

Painting the mixer machine surface and transporting trucks with white or lighter color and covering them with wet burlaps minimizes the radiation effects. Also, reducing the time between water added during concrete mix and concrete pouring negate the workability loss.

Finishing, and curing of concrete

The next important precautions to be taken are in placement, finishing, and curing of concrete. The speed of placement and finishing helps to minimize problems in hot water concreting. Protection and curing have to be started immediately after the surface is hardened enough. This can be in the form of covering the concrete surface with wet burlap, curing compounds or sprinkling of water initially. Moist curing shall commence once the concrete surface has attained some degree of hardening sufficient to withstand surface damage. Continuous curing is important, because volume changes due to alternate wetting and drying promote the development of surface cracks.

Once concrete cubes are cast for testing of the concrete for compressive strengths, adequate protection to be made for cube specimens from being exposed to direct sunlight or else evaporation of water in the cube will lead to lower compressive strength reported when tested for 7 days and 28 days.

It is important to take adequate measures at every step involved in concreting from material storage to concrete mixing, transportation, placing, finishing, curing and concrete cube casting.