When purchasing Glulam, you must prioritize strength classes (e.g., GL24, GL28, GL32) which indicate the characteristic bending strength. Ensure the adhesive type used is appropriate for the intended use; Phenol-resorcinol-formaldehyde (PRF) is essential for exterior or high-moisture applications (Service Class 3), while Melamine-urea-formaldehyde (MUF) is common for interior use. Additionally, verify the lamination thickness, typically between 30mm to 45mm, to ensure structural stability and minimize internal stress.