NASCLA Accredited Commercial General ContractorWoodMedium
A contractor is installing pressure-treated wood components for exterior decking on a commercial building. The plans specify lumber treated with 'ACQ'. What specific type of wood treatment does ACQ refer to?
- AArsenical Copper Quinolone
- BAmmoniacal Copper Zinc
- CAcid Copper Chromate
- DAlkaline Copper Quaternary
Show answer & explanationAnswer & explanation
Correct answer: D. Alkaline Copper Quaternary
ACQ stands for Alkaline Copper Quaternary, a common type of wood preservative used for pressure-treated lumber that provides protection against fungal decay and insect attack.
Why the other options are wrong
- A. This is an incorrect combination of terms.
- B. Ammoniacal Copper Zinc (ACZA) is another type of treatment, but not ACQ.
- C. Acid Copper Chromate (ACC) is a different treatment, less common now.
ACQ Wood Treatment
A water-based wood preservative containing copper and a quaternary ammonium compound, commonly used for pressure-treated lumber.
- Replaced CCA for many residential and commercial applications due to environmental concerns.
- Provides protection against fungal decay and insect infestation.
- Requires specific fasteners (e.g., hot-dipped galvanized or stainless steel) to prevent corrosion.
Memory trick: ACQ's copper and quats keep wood from rot.