The main material, forming the roof of the Holy Ka'bah, is wood. The ideal type to be employed in the roof of the Holy Ka'bah should have the following qualities:
Strength and durability.
Flexibility in a hot, dry climate.
Resistance to white ants, bacteria, mould and humidity.
The trunks should not be more than 10 metres in length, stress levels equal and each with a diameter of slightly less than one metre after striping and preparation.
These specifications were given to Internatiomil Timber Research Centres in Europe, Australia and New Zealand. As a result of the centres' studies, teak wood from its natural environment (not planted in other areas) was recommended for its strength. durability and long life. The length of its trunk is usually ten metres with diameters of 1.5 metres. It repels white ants and may be dried in a short time with the least degree of shrinkage, and if oiled it acquires a very beautiful gloss. It had already been used in Saudi Arabia in other projects of the Custodian of the Two Holy Mosques.