The moisture content recommended for doors is
- A4-8%
- B8-14%Correct
- C12-20%
- D2-4%
Solution
Concept
Recommended moisture content for timber doors
Formula
NONE
Step-by-step solution
1. Timber used for joinery and interior fittings must be seasoned to an optimal moisture content to prevent warping or shrinkage. 2. Standard building specifications recommend a moisture content range of 8% to 14% for door shutters and frames. 3. Therefore, the recommended moisture content for doors is 8-14%. Answer: B
Explanation
Timber used for internal joinery like doors should be seasoned to a moisture content between 8 and 14 percent to match indoor relative humidity levels. Maintaining this equilibrium moisture content prevents significant swelling, shrinking, or warping during atmospheric seasonal changes. Moisture contents above or below this range can lead to structural distortion or fungal decay.
Why the other options are wrong
A) A moisture content of 4-8% is too low and applies to interior furniture in dry climate zones. C) A moisture content of 12-20% is suitable for structural timber exposed to external weather. D) A moisture content of 2-4% is excessively dry and causes warping or cracking in timber.
Shortcut
Recommended moisture content for timber doors is 8-14%.
Common mistake
Assuming a lower moisture content range typical for structural timber in dry regions instead of the standard 8-14% for doors.
Correct answer: B) 8-14%