Awareness and Implementation Challenges of the Green Retrofitting in Building Enclosure in the Nigerian Construction Industry

This research work aims at examining awareness and implementation challenges of green retrofitting in building enclosures among professionals in the Nigerian construction industry. The study identifies the varying green retrofitting used in building enclosures and investigates its level of awareness and the factors affecting its adoption among professionals in the Nigerian construction industry. The sample was 100 comprising professionals in the construction industry selected randomly using cluster and purposive sampling techniques; and the response was 60%. Data were analyzed using frequency, mean and rank. The findings from the study revealed that out of the 20 green retrofitting used in building enclosures, the construction professionals are more aware of green roofs, high-quality glazing, reflective roofs, energy-efficient windows and doors, and shading device which include louvers. Also, top among the implementation challenges of green retrofitting used in building enclosure among construction professionals include limited knowledge, cost of fixing green retrofitting, skills gap, reluctance to adapt, and poor infrastructure are the major factors. The study recommend that government and professional bodies should sponsor innovative training approaches aimed at addressing skill shortages. This could be in form of schemes such as micro credentials and on-the-job training.


Introduction
Green building technology (GBT) is a rapidly emerging technology in higher-income countries around the world to counter the negative environmental effects of construction activities.Green building is an effective alternative to traditional building with significant role in reducing or eliminating the negative impacts of construction activities on the environment and on climate change [1].Studies [1,2] show that green building has revolutionized the construction industry of several nations, including many IOP Publishing doi:10.1088/1755-1315/1342/1/012023 2 countries in Europe, Asia and the Americas.Environmental and resource friendly structures and processes are regarded as green building [3].While it is easy to incorporate green technology in newly conceived construction development, it may be necessary to upgrade or modify existing structures to bring them to compliance with required standards of green technology.This upgrade/modification is termed retrofitting [4 -6].
It is however sad to note that the Nigerian construction industry is nowhere to be found as far as the implementation of this technology is concerned [7], hence, this research work aims at examining awareness and implementation challenges of green retrofitting in building enclosures among professionals in the Nigerian construction industry.The study identifies the various green retrofitting technologies used in building enclosures and investigates its level of awareness and the factors affecting its adoption among professionals in the Nigerian construction industry.The study is significant as it will bring to fore the key issues in the implementation of green retrofitting technology in the Nigerian construction industry, and its findings will be a useful aid in better adoption of the technology in construction development in the country.

2. Literature Review
The awareness and adoption of green retrofitting technology has been poor in Nigeria [7].Green retrofitting technology was inadvertently adopted in building production in times past when buildings were proven to satisfy thermal comfort, greenery, aesthetics, environmental friendliness and economic value, with the use of sustainable building materials such as earth, timber, straw and stone to produce simple, liveable and affordable houses [8].It noted that these materials were generally locally found, affordable, and environmentally friendly.Today, modern and fashionable materials reflecting only aesthetics and prestige have permeated building production in the society.Nevertheless, it observed that the building industry has begun to revert back to sustainable practices in buildings just like the rest of the world is doing.Researches [7,9] noted that Nigeria is still in the awareness stage about green building and that the low level of awareness ranks very high among the barriers to adoption of green building by the construction industry in Nigeria.
Retrofit technologies were categorized into 4 main technical systems, namely, mechanical, plumbing, electrical and building envelope systems [10]; while another study [11] identified 27 retrofitting technologies and categorized these under 4 building systems of electrical, enclosure, mechanical and renewables systems; and 36 green building technologies were divide into 7 groups of indoor illumination systems, control systems, energy and water conservation systems, renewable energy systems, energy and water recovery systems, systems to ensure air quality and systems to maintain comfort zone temperatures [12].Green retrofitting technology can also be applied in several areas, including but not limited to lighting, heating, ventilation and air conditioning (HVAC), water systems, building automation system, insulation and on-site energy generation [13].
IOP Publishing doi:10.1088/1755-1315/1342/1/0120233 Lighting retrofits are often used by clients with minimum challenges.It has been proven that lighting levels can be increased while energy consumption can be reduced up to 70% when lighting fixtures are upgraded.Building owners have confirmed that this alteration has yielded significant cost saving for them.Examples of lighting retrofitting include replacing old light fittings with modern fixtures; timers or sensors can be added on the fixtures that are occasionally employed for control when natural light is available.HVAC systems require regular maintenance for optimum performance, low energy consumption, heat transfer and environmental impacts.
Clean, potable water is important for human consumption and it is becoming increasingly expensive and difficult to get this in many places.Several water conservation strategies have employed to lessen water consumption.Some of these include upgrade of sanitary and plumbing fittings.Countries like United States of America have legislation on maximum water quantity to be used in plumbing appliances and components in addition to recycling and reusage of water.The building automation system is a mechanism that manages all the operation systems including the HVAC system, lighting and the appliances, etc. within the building; it helps to reduce utility costs and maintenance and improves user comfort.For example, when set to predetermined schedules, the system can maintain the temperature, air quality, and lighting inside the building.Also, it can monitor and record energy usage accurately.It can identify and locate problems, system failures or unusual energy use whenever it occurs.Further, it can be remotely controlled, even online and is capable of immediate intervention in emergency cases.
Insulation helps to reduce the need for heating and cooling, thereby reducing demand on energy.During winter, good insulation helps to retain the heat and traps cool air inside in summer.Well insulated windows help in effective building insulation [13].It studied that where windows cover 15%-25% of the building envelope, it might result to total heat loss within the building up to 40%-70%.Hence, it was proven that significant cost savings can be achieved through window retrofitting and insulation; use of double pane windows in place of single panes; heat transfer between interior and exterior of buildings can be reduced by insulation; and encourage use of window frames with low U-factor.
When walls are well insulated, it greatly helps in reducing required heating or cooling energy within a building.However, an insulation upgrade for walls is uncommon because it is costly.The use of lighter colors on building walls is an affordable way to make walls less absorbent of heat, as bright or light painting have higher tendency to reflect light effectively.Further, the use of double doors with weather-stripping in place of a single door entrance is better.
Many on-site power generating systems are in use nowadays that replaces the harmful and depleting fossil fuel.They include solar PV, solar thermal, wind turbines and geothermal energy systems.Ultimately, environmental conditions of a region could determine the system to adopt.The challenges of retrofitting technology include education and awareness; technology; finance; policy; and availability.With respect to the issue of knowledge and awareness, the study noted that knowledge and understanding of language around green retrofits is limited.Most of the stakeholders in the application of retrofitting in buildings are yet to get familiar with the terminologies and concepts in use within the retrofitting business case.There is also gaps in knowledge and skills in the workforce.There is still a serious lack of knowledge and experience among contractors and building owners about green retrofit technologies, specifically in heat pumps and air tightness.Lack of practical experience and resistance to change of both building owners and tenants to engage in a new technology and process are challenges as well, in addition to lack of sustainability knowledge.Technology challenges include supply chain availability and volatile cost; highly variable prices and volatile costs usually arise due to high demand across the globe to meet climate targets; and underlying grid infrastructure.It is important to establish enabling technologies and infrastructure for the effective delivery of retrofitting systems.Financial challenges comprise high initial cost of green retrofitting projects; high cost of skilled labour and green retrofit technologies; return On Investment: (ROI) Lack of standardized information about the ROI on retrofit projects; and lack of funding.Policy challenges are lack of national and provincial green retrofit policy and regulation; and low investment and involvement from the government and private sector.In conclusion, it has been observed that there is inadequate availability of building materials and technologies used in green building development.

3. Research Method
Survey research design was employed for this study [14].The population of the study were construction professionals in Ekiti State, Nigeria.Questionnaires were administered to 100 sampled professionals, with a response rate of 60% [15].The questionnaire used Likert Scale 1= strongly disagree to 5 = strongly agree [16] to determine the level of awareness and use of the various green retrofitting technologies in building enclosures in Nigeria.The questionnaires were administered online through various WhatsApp platforms of groups and individuals within the construction industry.Samples were selected using purposive method [17].The retrieved data as presented in charts via Google forms were discussed and inferences obtained.

Demographic Information
A total of 60 professionals responded to the questionnaire survey.The respondents consisted of professionals from 7 professions in the construction industry.Fig. 1 below shows the data of respondents based on their professional affiliations; F Figure 1: Professional Affiliation of Respondents Figure 1 shows that builders (40 responses) constitute the highest number of respondents.Others are quantity surveyors (7), architects (4), estate surveyors/facility managers (3), town planners (2) and land surveyors (2).
The respondents have acquired satisfactory academic qualifications and construction experience to be able to provide accurate responses to the research enquiries.Figure 2 and Figure 3 show the academic qualifications and years of experience of the respondents; From Figure 2, it can be observed that 19 of the respondents have HND qualification, another 19 respondents have Masters degree, 13 have Bachelors degree and 10 have doctorate degrees.Figure 3 shows that 33.3% of the respondents have above 20 years' experience, 23.3% have 6 -10 years' experience, 18.3% have less than 5 years' experience, 13.3% have 11 -15 years' experience and 11.7% have 16 -20 years' experience.Since more than half of the respondents (58.3%) have above 10 years' experience, the responses obtained are expected to be reliable.
The research enquiry sought to identify the sector within which respondents were employed and their position within their organization as shown in Figures 4 and 5

Awareness of Green Retrofitting Technologies in Building Enclosures
Literature suggests that there are 20 green retrofitting technologies in building enclosures.Table 1 below shows the responses to the level of awareness of these technologies.Respondents submitted their opinions on the various research enquiries in the questionnaire which used a 5-point Likert scale with the parameters 0 -Not Aware, 1 -Slightly Aware, 2 -Not Sure, 3 -Aware and 4 -Very Aware.Conversely,researches [7,9] did not mention any of the challenged discovered in this study as challenges but they however agreed that green retrofitting technologies faces a lot of challenges in Nigeria.

Conclusion
The study investigated the awareness and challenges of green retrofitting technologies in the Nigerian construction industry.

Figure 4 :F
Figure 4: Nature of Employment

Table 1 :
Awareness on Green Retrofitting Technologies in Building Enclosures

Table 2
above shows that all the nine factors are significant.Limited knowledge, cost, skills gap, reluctance to adapt and poor infrastructure are the major factors limiting the adoption of green retrofitting technology in Nigeria.The other identified factors, that is, lack of sustainability knowledge, lack of green retrofitting technologies, inadequate availability of materials used in green building and lack of green retrofit policy and regulation are also significant factors.
The study was carried out empirically among construction professionals in Ekiti State and the following conclusions are made: There is average awareness of green retrofitting technologies investigated among the professionals, in alignment with the discovery of previous work[7].The awareness of the professionals is highest with the use of green roof and cool roof, followed by highquality glazing, reflective roofs, energy-efficient windows/doors and cross ventilation among others.High R-value Roll-up receiving doors have the lowest awareness record, others include clips, frames, cladding; thermal break technology; insulation and air barrier systems; and high efficiency curtain walls.All the factors constituting implementation challenges to green retrofitting technology adoption had mean scores above average.This implies that all the listed factors are to be considered as matters requiring serious attention.Limited knowledge ranked highest among the factors, this is followed by cost of green retrofitting technologies, skills gap in retrofitting technologies, reluctance to use new technologies, poor infrastructure to support green retrofitting technologies, lack of sustainability knowledge, lack of green retrofitting technologies, inadequate availability of materials used in green building and lack of green retrofit policy and regulation.The government and professional bodies should sponsor innovative training approaches aimed at addressing skill shortages of professionals.This could be in form of schemes such as micro credentials and on-the-job training.2. Firms and individual professionals should also sponsor research and development programmes through seminars and workshops targeting cost professionals and designers to educate them on the techniques available.