# Waste Reduction Methods Used in Construction Companies with Regards to Selected Building Products
## 5 Discussion of Results
The results of the current research are partially confirmed by the studies conducted by [PERSON] and [PERSON] [25]. The authors indicate that construction companies in the United Arab Emirates mainly use methods to prevent the formation of construction waste such as: (i) appropriate storage of products, (ii) ordering products in the right amount, and also (iii) training and raising awareness of staff. In the present research, these three basic methods have also been classified as being used very often in construction companies. In turn, according to the research carried out by [PERSON] [27], the most important techniques used to minimize construction waste include training of construction personnel, training of employees in product management, improved supervision, good coordination between the supplier's personnel and the construction personnel in order to avoid over-ordering, and proper storage and use of products on site. One of the analyzed methods of reducing construction waste is the use of prefabricated elements. This method is included in the set of methods that are rarely used, possibly due to the structural characteristics of local buildings. The research conducted by [PERSON] and [PERSON] [28] emphasized that prefabrication technology offers many benefits, such as lower costs, shorter project duration, better quality of workmanship, and the minimization of waste. However, in order to minimize the amount of waste in construction projects, there is a need to constantly raise the awareness of employees by increasing the amount of management training. Special consideration should be also given to methods such as (9) waste segregation on site, (10) designation of a place for waste segregation, and (11) reuse of products within the construction. These methods are primarily applicable to concrete, masonry, and ceramic waste. Many studies have been conducted on the possibility of reusing aggregate obtained from such waste. Researchers from China investigated the use of recycled sand, instead of natural sand, in the production of the concrete suitable for 3D printers [29]. The use of recycled sand in the 3D printer concrete mix is believed to significantly improve the durability of 3D printed concrete structures. Furthermore, researchers from Portugal examined the possibilities of using recycled fine-grained construction and demolition waste as a backfill material for geosynthetic reinforced slopes [30; 31]. The crushed concrete can also be used in geotechnical projects, e.g., the use of very irregular concrete fractions for the formation of stone columns in weak soils [32]. The benefits of reusing concrete waste on construction sites are related to the possibility of using it locally without incurring significant transport and storage costs. This is of great importance for the protection of the environment and the sustainable development of construction. The chi-square test results show that for all of the groups of building products, the frequency of using construction site monitoring systems (method 4) depends on the size of the company, i.e., the frequency of usage of the method increases along with the size of the company. A significant statistical relationship was found between the size of a company and the use of the following seven methods of reducing construction waste: use of monitoring systems, use of prefabricated elements, reuse of products on the construction site, appropriate involvement of subcontractors, adequate storage, training of employees in waste management, and proper transport and unloading. These methods are used more frequently as the company expands in size, which shows that the larger the company, the more committed employees are to reducing waste. Moreover, the number and type of a method that meets the above condition vary depending on the type of construction product.