Timber grading in Nigeria

Nigeria timber is graded into 7 groups.

From N1 - N7 ( according to NCP 2: 1973)
u can get copy from Standard Organization of Nigeria SON.

N1 is the highest strength Class

N7 is the weakest strength Class.

Most construction work in Nigeria is done with grading from N4 - N7 ( soft woods).

Some of its grading includes;

N1 - strongest wood i.e Ekki.
N2 - AYO
N3 - iroko ( teak),
N4 - Abura
N3-N4 - Obeche
.
.

N7 - Araba, Apu (softest wood)

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