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The focus of this research was to study the utilization of residues from bamboo (Dendrocalamus giganteus) lamination in the manufacturing of panels for structural purposes. Bamboo particleboards were produced under three conditions: pure boards, reinforced with bamboo laminas, and with treated particles. Castor oil-based polyurethane was the resin binder, in view of using lower toxicity materials. The mechanical tests were performed according to Brazilian Standard (NBR) 14810-3 (2006) and European Standard (EN) 310 (2000). The results were superior to those recommended by these and other standards for internal adhesion resistance, modulus of rupture, and elasticity in static bending, as well as to the results of other studies. Starch treatment was an unnecessary stage. According to the conditions of this process, the studied panels showed a good potential for construction use. Moreover, the bamboo particleboards are an economically viable, environmentally friendly, and sustainable alternative for the use of waste generated during the processing of Dendrocalamus giganteus bamboo species, allied with castor oil-based polyurethane resin. The reinforced particleboard and its production process are being licensed as an Innovation Patent in Brazil, (BR 1020130133919-1-2013).

Particleboards were made using particles from sugarcane bagasse and eucalyptus residues of the pulp industry. The particleboard properties were evaluated according to ABNT NBR 14810-1 (2013), ABNT NBR 14810-2 (2013), and ANSI A208.1 (1999) standards, which compared the efficiency of castor oil-based polyurethane resin (PU-Castor) and urea-formaldehyde resin (UF). The particleboards were composed of 60% wood particles and 40% bagasse, with a 10% adhesive dose based on the dry mass of particles. The following parameters were evaluated: apparent density, moisture content (MC), thickness swelling after 24 h, modulus of rupture (MOR), modulus of elasticity to static bending (MOE), and internal bond strength of panels (IB). The results obtained demonstrated the potential use of eucalyptus and sugarcane bagasse residues in the production of high-density particleboards. The panels produced with PU-Castor showed greater efficiency, and their physical and mechanical properties were compatible with the requirements of the Brazilian standard for P4 panels (structural panels for use in dry conditions) and the American standard for H-3 panels (high industrial density).

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Brazilian timber housing producers were evaluated through a survey, which was based on face-to-face interviewing supported by a semi-structured questionnaire. Derived from expansive research, this paper aimed to identify labor size and to characterize economic size from this production sector. The sampling process evaluated 50.95% (n = 107) of all producers (n = 210) whose performance was considered close to ideal. This sector is mostly concentrated in micro and small-scale companies, though a small portion of medium-sized companies owned by sole proprietors, families, or small groups of entrepreneurs does exist. Due to compact sizing, no producer was classified as an industry or a large corporation. The main contrast was indicated by the number of direct jobs, whose estimation was about 3,700 workers for the whole studied sector, representing 1% of the overall Brazilian timber industry. Around 95% of timber housing producers are considered micro or small from a labor perspective. Unprecedented information could support discussions for the creation of assertive public policies.

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Mechanical characteristics were evaluated of wood-bamboo-based particleboard having the proportions of 100% wood and 0% bamboo, 75% wood and 25% bamboo, and 50% wood and 50% bamboo. This particleboard used Eucalyptus urophylla × grandis wood, Dendrocalamus asper bamboo, and castor oil-based polyurethane resin. Through destructive testing, the values of perpendicular tensile, static bending, modulus of elasticity, and screw pullout strength in the top and face surfaces were analyzed. For 0%, 25%, and 50% bamboo the values were 1.68 MPa, 1.37 MPa, and 1.4 MPa, respectively, for perpendicular tensile; 15.2 MPa, 17.6 MPa, and 18.5 MPa, respectively, for static bending; 2466 MPa, 2694 MPa, and 2922 MPa, respectively, for modulus of elasticity; 1256 MPa, 1922 MPa, and 1362 MPa, respectively, for screw pullout strength in top; and 1392 MPa, 1342 MPa, and 1414 MPa, respectively, for screw pullout strength in face. These results were superior to those presented by ABNT NBR 14810 (2013) and ANSI 208.1 (1999). After performing a Tukey test at 5%, the values for each treatment did not show a significant difference among them.