What are the standard length intervals for teak squares?

Standard lengths range from 1.0 m to 5.0 m, increasing in steps of 0.25 m.

Are negative tolerances permitted on the cross-section dimensions?

No, the tolerance on width and thickness is strictly +3 mm and -0 mm.

What is the main criteria for grading teak squares?

Grading into Grade I and Grade II is primarily based on the permissible extent of natural defects such as sapwood, knots, shakes, and splits.

IS 3731

: 1985

teak squares

CurrentSpecializedSpecificationMaterials Science · Timber and Timber Stores

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This standard prescribes the requirements, dimensions, tolerances, and grading rules for teak squares (Tectona grandis) used in construction, joinery, and general carpentry. It categorizes teak squares into grades based on the presence and extent of natural defects like knots, splits, and sapwood.

teak squares

Quick Reference Values

standard length range1.0 m to 5.0 m

length increments0.25 m

standard cross section range100 mm to 250 mm

cross section increments25 mm

tolerance on length+50 mm, -0 mm

tolerance on width and thickness+3 mm, -0 mm

Practical Notes

Inspect teak squares carefully for hidden end-splits which might propagate during seasoning.

Moisture content should be checked as per IS 287 before finalizing dimensions, as shrinkage can affect the final squared dimensions.

Sapwood proportion is a key differentiator between grades and significantly affects the long-term durability and termite resistance of the teak.