Red Seal Carpenter Practice Exam

When should backfilling of a recently poured foundation wall be done?

1. Backfill as soon as possible for safety and to assist in constructing the floor system.

2. First construct the floor system, backfill, then apply the dampproofing.

3. Install the vapor barrier, construct the floor system, then backfill.

4. Install the dampproofing, construct the floor system, then backfill.

The correct answer is: Install the dampproofing, construct the floor system, then backfill.

Backfilling a recently poured foundation wall is best approached when the structural integrity and moisture control of the foundation are ensured. The correct procedure is to first construct the floor system. This is critical because the floor system provides essential support and stability that may be compromised if backfill is applied too early or before the floor is in place. By completing the floor system before backfilling, the construction is better equipped to handle the pressures exerted by the surrounding soil, reducing the risk of wall displacement or cracking. Additionally, this approach allows for the installation of dampproofing afterward, which is vital to prevent moisture from penetrating the walls and helps protect the foundation from water damage. In contrast, backfilling before the floor is in place can lead to various issues, including structural weaknesses and increased difficulty in managing moisture through proper dampproofing application. Thus, ensuring the sequence of construction is crucial for the durability and effectiveness of the foundation.