Sustainable Construction and Structural insulated panels

Sustainability, a word most often discussed, yet least understood is a topic of interest in today’s growing society. With various interpretations offered, some treat sustainability in a superficial way. However, for many businesses, nations, and individuals that believe in the future sustainability has to offer, the word is a serious one aimed at promoting efficient use of resources, a chance at stable economic growth, and continued social progress. In modern society, construction plays a part in how one lives, goes to work, and buys and purchases services/products. If sustainable construction can provide a chance for less consumption, less use of resources, and a means of promoting a way of living in line with balance and moderation, then perhaps the world will be open to change, especially if the cost to do so is less than traditional methods; structure insulated panels are a cost-effective green solution aimed at use in large and small-scale projects.

Structural insulated panels (SIPs) are a material that not only save owners money but allows for easier operation and maintenance of homes and buildings (Kibert, 2016). Construction is an important part of modern society. The demand for adequate housing has grown along with costs for construction (Kibert, 2016). Urban areas require construction of large buildings where people live in apartments, co-ops, and public housing. These buildings may account for over 40% of energy consumption (Kibert, 2016). In fact, construction for the European Union has led to an estimated 40% of every human-produced waste (UNEP, 2001). While recent trends may suggest less consumption through new building techniques and materials, it is sustainable construction that directly tackles the problem of excessive waste witnessed using traditional methods. Sustainable construction in the form of SIPs is an easy and cost-effective solution more people need to use.

Sustainable building aims at addressing the bigger and much more significant macro-flaws in the approach to construction (Feigin & Magwood, 2014). For example, toilets were made in the past to flush with a large amount of water used to remove waste. However, recent building methods have been generated to allow for toilets with ‘half-flushes’ in order to conserve water in areas with reduced access (Feigin & Magwood, 2014). The same can be said of SIPs. Structural Insulated Panels are a high performing building material for use in light commercial and residential construction. SIPs consist of insulating foam cores placed between two structural facings. The foam core in the middle with the exterior and interior sheathing on either side (Feigin & Magwood, 2014). With manufacturing of SIPs done in factory-controlled conditions, it has the potential to fit almost any building plan or design. The result is a building system that is cost-effective, energy efficient, and extremely durable.

The cost-effectiveness comes from the insulated core. When constructing houses for example, traditional construction methods means having to inject or put insulation in-between the frame of the house and the walls. Using SIPs removes that additional step leading to less expenses overall. This is because of reduced indoor heating or cooling costs (Feigin & Magwood, 2014). When a house has insulation, it allows for less heat or cold air to escape the home. Additionally, taking out the insulation step means less labor spent on building the home or office building. Many designs often need a skilled hand to cut and fit pieces together. However, SIPs can be made in the factory to exact specifications, further reducing construction time and expense.

SIPs are “one of the most airtight and well-insulated building systems available, making them an inherently green product. An airtight SIP building will use less energy to heat and cool, allow for better control over indoor environmental conditions, and reduce construction waste” (Padmini & Manoj Kumar, 2015, p. 1). When it comes to how SIPs are made, OSB is used on the exterior and interior sides and comes from fast-growing, small diameter trees. These kinds of trees are harvested from plantations leaving old-growth trees undisturbed. The EPS foam that makes up the core, is a recyclable material, fully inert in the environment (Kibert, 2016). EPS foam can be used as a soil-additive and requires less energy than is needed to produce fiberglass insulation. In addition to requiring less energy to be made, SIP panels release no harmful volatile organic compounds. The airtightness of the construction leads to reduced environmental and chemical allergies inside (Kibert, 2016).

Along with coming from green-sourced materials, SIPs can be transformed into composite structural-insulated panels (CSIPs). CSIPs “are novel prefabricated elements for structural applications. They are made from glass–fiber reinforced magnesia cement boards as facesheets and expanded polystyrene foam (EPS) as a core. CSIPS overcame several deficiencies of traditional structural insulated panels (SIPs)” (Smakosz & Tejchman, 2014, p. 1068). CSIPs offer the versatility of SIPs but further promote the green message by using materials that do away with the need for wood altogether. CSIPs are an evolution of SIPs that allows for greener construction and enhanced sustainable construction. “Constructing green buildings that these resources more efficiently, while minimizing pollution that can harm renewable natural resources, is crucial to a sustainable future” (Padmini & Manoj Kumar, 2015, p. 1).

With global warming becoming a reality and extreme weather conditions ever-present, constructions methods need to take into consideration how to overcome challenges in these conditions while also remaining cost-effective. Structural insulated panels were used in a recent study to see if they can hold up in extreme cold conditions of ?20 °C and ?40 °C (Kayello, Ge, Athienitis, & Rao, 2017). Monitored with thermocouples the eight kinds of structural insulated panels were then subjected to varying pressure differences and heat of up to 62 °C. The more complex joints did not have a good enough air seal. However, the SIPs managed to maintain integrity more than traditional building materials like wood (Kayello, Ge, Athienitis, & Rao, 2017). If improvements are made, the researchers of this study suggest less dependency on the tape to fasten SIPs onto the building frame. “All the joints can be improved to be less dependent on the tape, though the joints most susceptible to moisture damage and mold growth are the top joints since moist indoor air tends to exfiltrate at those locations due to stack effect” (Kayello, Ge, Athienitis, & Rao, 2017, p. 345).

As earlier noted of the evolution of SIPs into CSIPs, there are other forms of SIPs being made as well. Ten years ago, a study analyzed the benefits of a then, new kind of wall panel called the phase change material structural insulated panel (PCMSIP). The use of PCMSIP led to significant average daily heat transfer reductions and allowed for further examination in how SIPs can be manufactured to suit the diverse needs of customers. “The average reductions in daily heat transfer across the PCMSIPs were 33% and 38% for concentrations of 10% and 20% PCM, respectively.” (Medina, King, & Zhang, 2008, p. 667). If customers require a greener solution without the use of wood, they can use CSIPs. If they want greater heat transfer reductions, PCMSIPs are an option. These demonstrate the kind of methods for use in construction of homes, buildings, and both large and small-scale projects.

SIPs are cost-effective when taken into consideration the lesser cost of labor and long-term lesser cost of heating and cooling the home/building (Kibert, 2016). With recent trends in modifying SIPs, there may be an even greater chance at saving money. Composite structural insulated panels may see potential use in construction of lighter large-span roof structure thanks to a high strength to weight ratio (Du & Uddin, 2016). Methods are being invented to improve stiffness in CSIPs. A method Du & Uddin discussed involved folding, aimed at improving the moment of inertia. The second method used was curving. Curving transforms structural bending moments using what is known as the principle of arches (Du & Uddin, 2016).

By applying these methods, namely the folding method, they saw a future use for CSIPs in large-span roof structures. “The results of geometrical nonlinear analysis demonstrated CSIPs folded shell structure has 5 times larger nonlinear buckling load capacity than the CSIPs thin shell. CSIPs folded shell structures have excellent structural configurations and extensive application prospects in large-span roof structures” (Du & Uddin, 2016, p. 1). Large-span roofs are used for large-scale construction projects. If SIPs in this form can be used for large-scale projects versus traditional methods, the overall cost-savings in reduced waste, reduced labor, and reduced energy costs makes for a supremely superior building material over traditional options.

Furthermore, use of wood can be costly. To source the wood, grow the wood, and produce the panels in traditional SIPs, it involves roughly the same amount of money for traditional wood panels. However, CSIPs offer the most advanced and multi-functional building material that does away with traditional use of wood (Feigin & Magwood, 2014). CSIPs bring together fiberglass reinforced thermoset (FRT) with the rigid closed cell polyurethane foam insulation that lends to increased moisture resistance (Feigin & Magwood, 2014). By chemically bonding these materials together via chemical reactions during the manufacturing process, no tape or adhesive is used. SIPs use tape and can increase risk of delaminaton. However, CSIPs eliminate altogether that risk, making for a superb building material.
SIPs are still useful in areas that have low humidity and moderate temperature fluctuations throughout the year. However, for large-scale projects and projects in extreme weather conditions, the evolved form of SIPs, the CSIP is the better solution. CSIPs are an innovation brought on by the creation of SIPs and shows the potential growth for this building material in the future. Cost-effectiveness is in relation to less energy used and less waste. Both SIPs and CSIPs reduce waste and promote less energy used in sourcing and producing the materials.

Traditional construction costs in comparison are higher because old-growth trees tend to be cut for wood. This wood then is fitted onto a frame that requires foam insulation to be inserted or injected. The construction of traditional homes is not airtight, and air and moisture can seep in leading to higher energy costs. SIPs and CSIPs are both cost-effective and easier to produce because of the inherent design of the materials. The foam core used in both versions eliminates the need to use foam insulation and reduces labor costs through removal of additional steps seen in traditional construction.

In conclusion, structural insulated panels provide those looking for a sustainable means of construction, a way to save money and have high quality structures. Made in a factory and custom designed to fit and suit any design needs, SIPs offer the same cost as wood, but with less waste, less energy expenses to heat and cool the home, and less labor costs. This is because of the way SIPs are made. The foam core allows for a reduced need for insulation in the home. The airtight sealing further enhances this insulation and allows for outdoor allergens to not reach inside.

With new means of constructing SIPs, like CSIPs, less expensive materials may be used, and different methods of application can be performed. For example, the folding method allows for CSIPs to be used as large-spans roofs lending to use of SIPs in large-scale projects. Although SIPs do have flaws in extreme weather conditions, like reliance on tape, new methods may solve these issues relatively easily. That is because SIPs are building materials that offer growth and continued evolution compared to their traditional counterparts.

SIPs are a green solution from how the materials to make them are sourced to how much they reduce waste during the construction process. They are the definition of sustainable construction. The wood used for the panels are harvested from plantations, minimizing cutting down of old-growth trees. And with the recent studies showing their versatility and ability to change according to the demand, they make SIPs an effective option for residential projects and commercial large-scale projects.