How is the girth of a teak log measured according to the standard?

Girth is measured under the bark at the mid-length of the log. If there is a swelling or depression at the mid-length, the girth is measured just adjacent to it.

What are the standard commercial grades of teak logs?

Teak logs are classified into Special Grade, Grade I, Grade II, and Grade III based on their dimensions (length and girth) and the extent of permissible defects.

Are borer holes and rot acceptable in structural teak logs?

Live borer attacks and active decay/rot are strictly prohibited. Dead borer holes may be permitted to a limited extent in lower grades as specified in Table 2.

How is the length of the log measured?

The length is measured from the shortest distance between the two parallel end cuts, typically rounded down to the nearest multiple of 10 cm.

IS 4895

: 1985

teak logs

CurrentSpecializedSpecificationMaterials Science · Timber and Timber Stores

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This standard specifies the requirements, grading rules, dimensions, and permissible defects for teak (Tectona grandis) logs intended for conversion into timber for joinery, furniture, and structural purposes.

teak logs

Quick Reference Values

length measurement stepsMultiples of 10 cm

girth measurement stepsMultiples of 1 cm

minimum girth special grade150 cm

minimum length special grade3.0 m

minimum girth grade 1120 cm

Key Formulas

Volume (Quarter Girth Formula) = (g/4)^2 * L — Commonly used trade estimation for log volume

Volume (True Volume) = (g^2 / 4π) * L — Used for exact solid volume computation

Practical Notes

Girth must always be measured under the bark at the exact mid-length of the log.

If girth is measured over the bark, an appropriate allowance for bark thickness must be deducted as per regional norms.

Logs should ideally be end-coated to minimize end-splitting and checking during transit and storage.