Analysis of the effectiveness of using EPS sandwich panel versus lightweight bricks at residential project: Case study at residential houses in Jakarta

Effectiveness in material selection in construction projects has a major impact on the use of costs incurred during the construction period. The quality used must also be in accordance with standards based on building functions and have national standard quality. The implementation time on residential project construction projects that require work to be completed quickly in accordance with good results and in accordance with those stated in the contract must be carefully designed and planned. Data collected from literature and catalogues, and recorded from site will be analysed and discussed Therefore, the purpose of this study is to find out and choose the use of effective non-structural material as a wall for residential projects.


Introduction.
Architectural design is very rapidly developing, especially in terms of the appearance of the 'façade' of the building.The façade of the building is identical to the skin of the building or the outermost side wall of the building.Many variants of building materials for facades with cladding construction systems / curtain walls.About the new type of material 'EPS Panel' as wall cladding and curtain using the application of existing conventional construction.
The outer kin of the building is inseparable from the outermost wall or known as the building blanket.There are several types of exterior walls of buildings.Among other things, infill-walls that rest on the building structure directly.'Cladding' walls are described as versions that rest on the main wall and curtain-walls supported by frames of certain materials attached to the building structure.Polystyrene panel is one type of building material such as Styrofoam with both sides coated with galvanized steel wire (to avoid rust and to increase the flexural strength of EPS panel), the quality of steel wire coating is equivalent to U60 iron or with a tensile strength of > 600MPa, the results obtained are materials that can be used for walls, floors, and stair bodies, (Figure 1).[1].
This paper aims to compare conventional materials for walls with EPS walls for wall use.The method used in this study is a comparative study with samples of work and technical data.
EPS Panel.EPS or Expanded Polystyrene panel as a building material is an environmentally friendly product, because it has several advantages such as: [1-4] -Safe., does not release toxic and harmful substances and absolutely no side effects, without chlorofluorocarbons (CFCs) or hydrochlorocarbons (HCFCs).-Recyclable.no waste material is generated during the production and production process for EPS panels, which measured under field conditions will optimize the cut, and minimize waste.Any residual EPS recycling can be done directly at Plant Production.-Non-toxic, EPS panel material does not create allergic effects and does not damage health to those who manufacture or perform installation actions.-Does not propagate fire, EPS panel material can be used as a wall or ladder whose properties can dampen fire, the material does not produce fire, nor propagates fire.-Efficient.The environmental cost of expanded Polystyrene production is very little when compared to the amount of energy that buildings save using EPS panels EPS panels can be used in buildings that have the following characteristics: 1. Buildings with modular/repeatability properties 2. The construction system used is a frame system.3.There are not too many variants of existing lay out and details. 4. It will be suitable for buildings such as apartments, hotels, and boarding houses.
With the development of building material technology, the demand to speed up processing time has become a must, therefore many alternative building materials can be used, one of which is EPS (Expanded Polystyrene Panel), which has several advantages compared to conventional materials [4].

Methodology.
The methodology is to collect and analyse data.This study uses the case study method to take samples of boarding house buildings in Jakarta -Indonesia that use EPS as a building material for separation walls, also knowing the comparison of the use of EPS panels compared to conventional.Data collection using observation methods; to observe how to install EPS panels work in the project, to know the pros and cons of using materials.Data collected from literature and catalogues, and recorded from site will be analysed and discussed.
The implementation has also been carried out to find out what has been taught and applied directly in field work, in this case is the use of EPS panels as building materials for wall materials.
The variables observed and analyzed are as follows: 1. Overall volume of area to be done, 2. Comparison for the time needed, cost, waste, strength and other related 3. The resulting outcome 4. Economic value that can be obtained from the study 5. Comparison for sequence of work between EPS panel and AAC bricks

Analysis and discussion.
The case study used is a residential house in the PIK-Jakarta area, which accordingly to architectural design would apply double shield / secondary skin on the skin of the building, especially facing the West side.
EPS panel is a versatile structural element designed for floors, walls, partitions, roof and stairs.The typical EPS panel is generally manufactured with dimensions of 1200 m width, 3000 mm length and over all thickness range between 60-230 mm.The panels are finished at the site using minimum 30 mm thick shotcreting of cement & coarse sand in the ratio of 1:4 applied under pressure.The shotcreting coat encases the EPS Core with centrally placed steel welded wire mesh.[5] The panel also could be finished by manually plastered with the mixture of cement and coarse sand in the ratio of 1:4, applied by layers, which is between 5mm-8mm per layer.
Expanded Polystyrene, often referred to as EPS, is a kind of rigid, closed cell foam plastic.EPS properties have a low thermal conductivity, high compressive strength, is light weight, inert.It can be used as a building material or a design element, and can be molded into many shapes for a number of household uses as well.
The reason for choosing EPS panel material is the reduction of weight on the building structure, especially the façade area and accelerating the implementation time.
Comparison of the use of EPS panels with other building materials that are usually used for wall materials (lightweight bricks) can be seen in the picture below: List of questions to be analyzed related to the use of EPS panel material for the outer wall; [1] 1. Are EPS panel walls lighter than lightweight brick/AAC walls ?
A : The answer depends on the thickness of the wall.Below 12cm thickness, lightweight brick/AAC walls are slightly lighter than EPS panel walls.However, from the ratio of shear strength and compressive strength, lightweight brick walls are very weak compared to EPS panels.In addition, with absolutely no load-bearing function, brick walls are structurally inefficient.The most critical thing is, by only relying on mortar as an adhesive / double space between bricks, once this layer of mortar cracks off when shaken by an earthquake, there is absolutely nothing to keep these bricks from falling and harming the occupants of the building, no matter how sturdy the structure of a building 2. Are EPS panels safer in the event of a fire?A : Yes, EPS panel have been extensively tested for fire resistance (fire rating test) at the Settlement Research and Development Center in certified laboratory.Tests were carried out at a temperature of 1000 o C and proved that the b-panel® wall can last more than 120 minutes without any cracks, not even fire or smoke breaking through the wall.In addition, b-panels® used in structural applications (floor deck applied at an international school in Kuala Lumpur), were tested to a higher standard of 160/180 minutes at 10.000 C .The result again passed satisfactorily.Of course, this is because every EPS for b-panel® applications is always covered with high-strength plaster of at least 25 mm for finishing.

Are EPS panel eco-friendly?
A : EPS, is: easily recyclable (In Japan, 90% of EPS is recycled, supported by their already very systematic closed loop system).As an example; We recycle 100% of our panels' EPS, are non-toxic, use no greenhouse gases in their manufacture.EPS for building insulation on b-panels® is appropriate, where the high durability characteristics of EPS are in line with long-term use of buildings, even reaching cross-generation EPS. 4. Building a house with EPS... Styrofoam?This foam is commonly used for wedding decorations and packaging?Is it strong and can last a long time?A : The EPS layer provides absolutely add no significant strength once it is installed.This EPS layer at the time of installation could only functions as a formwork or formwork ("mold") to form two layers of reinforced concrete with a curve profile, where right in the middle of each curve profile, there is a high quality steel wire (U-50) which effectively makes the EPS wall a sturdy structural element.Unlike the formwork in general, this EPS layer is a permanent formwork, buried forever in a layer of concrete and does not need to be dismantled again after panel installation.Once the panel is installed, this EPS "formwork" changes its function, becoming a superior heat and sound insulation. 5. Why is b-panel®/b-deck®, with its smaller specific gravity, its acoustic insulation value (STC Value) even superior to heavy materials?A : The combination of two types of materials whose density is very different (weight-lightweight) gives a "Mass and Damper" effect where the heavy material, while holding vibrational energy (sound), will vibrate.A layer of lightweight and much more flexible material serves as the damper of the first heavy mass vibration, so that the vibration energy is not carried on to the other heavy mass.In addition, the presence of layers of different types of material produces a "decoupling" effect where it seems as if there are two different systems with small related things to do with each other.

Case study.
The object of the case study is a residential building, the design was an outer wall which is non-structural in the building system and functioned as a second layer wall / secondary skin need to be done in proper ways , such as durability, lightness, easy to install, and within the budget .The problems were : 1.Wall material must be strong and waterproof 2. Wall material must be lightweight, because it is located at the cantilevered area of the building 3. Wall material had long endurance after being finished 4. The work could be done easily and fast 5.The material cost still within the budget From those 5 problems to be solved, then there were 2 choices of material could be considered to be used, which were : 1.Light  Shown that EPS panel price would be approx.3 times higher compared to AAC bricks for the same volume area.The calculation of work time is obtained by dividing the area of the wall that must be done with the productivity of each job so that the results can be seen in Table 3.It can be seen that for the working time for the EPS panel more quicker compared to working time for AAC bricks installation, and the cost of installation services, the price of EPS panels is 40% cheaper than the price of lightweight bricks for the same area Waste / left over materials defined as all activities that require costs, directly or indirectly, require time, amount of power or require supplies that do not provide added value (Alarcon, 1994).

Comparison for wasted material
It can be seen for wasted material with EPS panel considered none or very small while with lightweight brick material there would be + 5% wasted material remain for the same area.The table show that installation cost of EPS panel would be + 25% lower compared to installation cost of AAC Bricks for the same volume of area.

Conclusion.
For owners, time savings will ultimately reduce overall budget costs, and minimize wasted materials.In addition, the advantages of non-financial problems that cannot be ignored, such as more comfortable occupancy (due to temperature fluctuations are maintained), quiet and privacy are guaranteed (due to good sound insulation) and safe from break-ins (because a double layer of concrete is reinforced on all walls).And for earthquake-prone areas (covering more than 80% of Indonesia), the use of EPS composite panels can mean saving one's life in the event of a major earthquake.Therefore, EPS manufacturers of composite panels in the country will expect the acceptance of this material as the material of choice for most constructions in the near future.
From the tables shown a cost comparison and time comparison, the higher EPS panel cost at unit price installation (about 2 times), will be covered by the faster the work can be done (about 3 times faster).
From the table shown all variants of EPS panels could not meet the minimum requirement for vertical compression test as mentioned in SNI 03-3122-1992, neither for grad A or grade B, so the EPS wall panel could not be used for structural wall element.
For contractors, the use of walls with EPS panels can adjust to project needs, especially in terms of productivity, research in the construction of Residential Houses in Jakarta-Indonesia is why choose walls with EPS Panel material because the owner needs lightweight materials and can be done in a fast time in the implementation of its construction.
[2] Majalah Techno Konstruksi.21 (2010).From all the charts shown, we set the perimeter for the conclusion of the study, which is : 1.The affect to the existing structure 2. The method to do the installation 3. The time needed to do the installation 4. The benefit and result of the product Each aspects had the value based on the objectiveness of the materials and the project needs, so we know the total value of the compared materials, listed in table below: The table show that EPS panel had more value number compared to AAC bricks material at 4 from 6 perimeter standard for wall work, it means EPS panel had better value to use compared to AAC bricks.

Figure 1 .
Figure 1.EPS or Expanded Polystyrene panel as building material [M-Panel system ,2017]

Figure 4 .
Figure 4. Case studi area [study case documentation] [3] IAI Magazine.2 (2009).[4] M-Panel.2010.Cara pemasangan Modern Panel Project.Tangerang: Modern Panel Indonesia [5] Manual for Expanded Polystyrene (EPS) Core Panel System and its field Application Sponsored By Ministry of Housing and Urban Poverty Alleviation, Government of India CSIR -Central Building Research Institute Roorkee June 2017

Table 1 .
weight bricks / AAC (Autoclaved Aerated Concrete) 2. EPS panel ( Expanded Polystyrene panel) Study case area [study case documentation] The table shown that the volume of area which will use EPS panel were 71,74sqm (14cm thickness) , and 5,6sqm (8cm thickness)

Table 2 ,
Material price comparison between EPS panel and AAC / lightweight bricks

Table 3 ,
Time estimated and labor cost comparison between EPS panel and AAC bricks

Table 4 ,
Comparison for material left over/wasted material between EPS panel and AAC bricks

Table 5 ,
Comparison for installation cost between EPS panel and AAC bricks

Table 6 ,
Comparison for benefit and weakness for EPS material VS lightweight bricksThe table show several benefits of EPS panel compared to AAC which is more suitable if used as a non-structural outer wall material such as in this case study7.Comparison for compression test between EPS panel and AAC bricks,

Table 7 ,
Comparison for compression test between EPS panel and AAC bricks [ITB Civil Engineering lab, PT Beton Elemindo Putra R&D]

Table 8 ,
Comparison for sequence of work between EPS panel and AAC bricks WEEKThe table show the difference for S curve sequences of works between EPS panel compared to AAC bricks

Table 9 ,
Comparison for sequence of work between EPS panel and AAC bricks