Q: Building a home using EPS….Styrofoam? The foam that is usually used for wedding decoration or packaging? Would it be strong enough?
A: The EPS layer within b-panel® does NOT provide any significant strength to the panels after they are installed. During panel installation, this EPS layer functions as formwork, to provide casting of two layers of reinforced concrete with wave pattern, in which at each of the wave pattern’s center, one can find a high-tensile (U-50) steel wire, which effectively make b-panel® wall to be a rigid structural element. Unlike typical formwork, the EPS layer is permanently covered by concrete, and does not require removal after panel installation. After the panels are installed, this EPS layer changes function into a superior thermal and acoustic insulation. We produce our own EPS foam under the brand b-foam® within our factory, with construction-grade quality: Fire-Retardant rated and of suitable density.



Q: Is b-panel® /b-deck® safe during fire?
A:Yes, b-panel® wall has been extensively tested for fire rating at the National Building Testing Center in Cileunyi, and was proven to withstand more than 2 hour of 1000C temperature without cracks, or breach of smoke and fire. Furthermore, for a structural application (floor deck at an international school in Kuala Lumpur), b-panel® was tested at higher fire standard of 160/180 minutes at 1000C, and passed this test successfully as well. The EPS foam in b-panel® in its finished form is always covered with at least 25mm thick of reinforced mortar. Secondly, PT. Beton Elemenindo Putra manufactures its own EPS foam called b-foam® in its in-house facility, ensuring that only Fire-Resistant (FR) grade raw EPS material is used for the manufacturing its EPS foam for b-panel®.


Q: Can b-panel®/b-deck® building withstand storm wind?
A:Yes, b-panel® is a material of choice in the regions around the globe which are prone to hurricane/typhoon-class wind hazard, such as countries in the Caribbean and sub-tropical Pacific Ocean. One example of this is applications in Haiti: http://www.signahaiti.com/signa/petion-ville-residential-3d-panel-construction . Similar to how b-panel® achieve superior earthquake resistance, the extensive steel reinforcement throughout b-panel® enables a 4 meter span building wall to withstand at least 1.2 KPa of pressure differential.


Q: Is b-panel®/b-deck®wall lighter than lightweight bricks/ AAC?
A: The answer depends on the wall thickness. Below 12 cm thick, lightweight bricks/AAC wall is slightly lighter than that of b-panel®. However, this slight weight advantage is insignificant, considering the much lower compressive and lateral shear strength of lightweight bricks compared to b-panel®, or even red bricks. Secondly, without functioning as load-bearing member, light brick wall is structurally inefficient. Its most critical weakness is that, by only relying on mortar as adhesive for the bricks, in the event that the mortar layer delaminates due to earthquake, there is absolutely nothing to keep brick chunks from getting loose, fall down, and harm the occupants of the dwelling, regardless how strong is the structural columns.



Q: Is b-panel®/b-deck®waterproof?
A: Despite b-panel®‘s superior resistance to humidity compared to conventional material, for locations which is susceptible to constant water exposure (Such as roof deck, bathroom floor, exterior wall above water channels), b-panel® needs similar treatment as commonly employed for regular walls, for example, application of waterproofing of suitable type.


Q: Why is b-panel®/b-deck®, despite its lighter weight, has better sound insulation (STC-rating) than heavier materials?
A: A combination of two types of materials with highly differing specific weight would give a “mass and damper” effect, in which the heavier material, while absorbing vibration energy (from sound) will also vibrate. The lighter, much more flexible material acts as damper, which in turn block the vibration energy from flowing to the second heavier mass. Secondly, with the multiple layer of different materials results in “decoupling” effect, where each layer act as if they are separate systems, with little connection between them.



Q: How about thermal and acoustic bridge?
A: b-panel® employs connector wire to bridge the two wire mesh matrices on each side of the EPS layer, to ensure the stiffness of the raw panel during plastering. Although metal is a good thermal and acoustic conductor, but its cross-section is negligible compared to the wall area, and thus the negative effect to b-panel®’s thermal and acoustic insulation properties is minimal, as proven in various testing. During the shotcrete plastering process, the entire panel surface is fully covered by reinforced concrete, without joint or gap that potentially create thermal and acoustic leaks.
For our b-deck® floor and roof deck panel, since 2014 we have improved its design so that thermal bridges has been completely eliminated.

Q: Can we hang picture, furniture, etc., on b-panel®/b-deck®wall?
A: The outer layer of b-panel®is a shotcrete-plaster with 2.5cm and K-150 concrete hardness minimum. With a 60kg per point load capacity, b-panel®wall has been proven to be able to hang heavier objects. At Hotel Santika in Jalan Raya Kuta, Bali, which employs b-panel® for all the partition walls, there was no major cracks observed throughout the walls used to hang LCD TVs (including a 37” unit at the lobby area), even after a major earthquake, which hit the area on September 2011.



Q: Semi-prefabricated: that means not as fast as precast?
A: Yes and no, depends on the locations and conditions of project site. With precast system, installation can be done rapidly, since there is no need for additional plastering or finishing of the concrete. On the other hand, by not needing heavy equipment, logistical challenge can be minimized, especially for low or medium rise projects, where construction activities is not centralized at one place in the case of most high-rise projects, but spread out over larger area. Other benefits of semi-prefab method, where the concrete is applied by means of shotcrete during plastering, is gapless monolithic structure, and thus monocoque rigidity can be achieved, and thermal and acoustic leaks from joints and gaps will be minimized.



Q: Environmentally-friendly? Styrofoam is environmentally-friendly?
A: EPS, or what is commonly known as “Styrofoam” (Although this is a misnomer, as Styrofoam is a trade mark of Dow Chemical Co. for their Extruded Polystyrene (XPS), whereas EPS is Expanded Polystyrene, a different type of material) is a notorious environmental hazard IF they are employed for one-time use, such as coffee cups, wedding decoration, and packaging. This is due to EPS’s lack of bio-degradeability, it takes a very long time for a Styrofoam piece to disintegrate, and for hundreds of years they will keep clogging our waterways and floating on lakes and oceans.

The fact about EPS is as follow: Easily recyclable (In Japan, over 90% of EPS are recycled, supported by their well-developed closed loop recycling program. Our own example: we recycle 100% of our panel’s by-product EPS), non-toxic, and does not employ greenhouse gas in its production process. The use of EPS for b-panel® is ideal, since the high-durability of EPS is aligned with the intended use: buildings are designed to have long service life, if possible even inter-generational in its use.
The more important point is, throughout its use, a b-panel® dwelling, its A/C electricity consumption will always be significantly lower (Estimated to be more than 30%), as A/C is the largest source of electricity consumption in a dwelling, at almost 40% of total consumption. In Indonesia, specifically the Jawa-Bali grid, more than 70% of electrical generation is by fossil fuel, and predominantly coal, the most environmentally harmful of all fossil fuels. Thus, by significantly reducing the A/C load, CO2 emission will significantly be reduced as well. With current b-panel® project portfolio (more than 50 projects to date), the CO2 reduction has almost reached 10 kiloton per annum. This effect is permanent and cumulative, as the project portfolio size increase with the wider adoption of the b-panel® system.



Q: Is b-panel® product available as precast?
A: Yes. PT Beton Elemenindo Perkasa (our sister company) has produced precast concrete facade panel with b-panel® inside, under the brand b-facade®. For production, we use the latest tilting table technology from Germany, for the best finishing quality of concrete panel and speeding up the production process. Compared to regular concrete facade, b-facade® has many advantages among which are lighter weight, and much better thermal and sound insulation compared to regular concrete facade.


The production process of b-facade®.



Q: Can expanded polystyrene (EPS) be used for a floating house?
A: Yes, because EPS consists of 98% air, its buoyancy is excellent. EPS is widely used for floating structures. Furthermore, EPS as floatation has much better safety factor than drum or other materials because EPS cannot easily sink, as its buoyancy is provided by millions of individual air cells. PT. Beton Elemenindo Putra has successfully offer this floating structures solution in the form of b-foam® floating pontoon (Link to http://b-foam.com/aplikasi-floating-structure.php)



Q: Is the building that uses b-panel®/b-deck®can be reused after a fire? How if the EPS has melted?
A: Yes. First, the building must be checked again whether or not the structure is still sound after a fire. In the event of fire, EPS will start melting at a temperature above 100oC although EPS is not burned. EPS melting will not disturb the structure because the EPS only serves as thermal and sound insulation. The walls should remain strong because the strength lies in microcolumns formed by concrete and wiremesh. If the structure is still sound, insulation replacement can be inserted again to recreate the thermal and sound insulation by the injection of polyurethane foam.


Q: Will EPS in the floor panel b-deck® shrink if loaded?
A: No, because EPS has a good compressive strength. During axial loading done on EPS, if its compressive force is within the limit of elasticity, then the EPS will return to its original dimension with no shrinkage. EPS with different density have different compressive strength as well. The diagram below shows the compressive strength for EPS of density 12 kg/m3. This diagram shows up to 25 MPa of compressive strength, EPS is still within the limit of elasticity.


EPS compressive strength of density 12 kg/m3