General information
These items are only few examples of wood material we may use.
Purchase of large quantities is under special regulations from ministry of natural resources or equivalent. Export may be forbidden or regulated. Check before purchasing large quantities.
Wood should be dried naturally or in kilns before use, a visit to the factory can be a good indicator.
Protection against termites is extremely important in wood building, it can be achieved with impregnation of waste engine oil mixed with diesel or specific insecticides products.
Treatment with Chromated Copper Arsenate (CCA) and with Creosote are highly toxic, often banned and not recommended for residential use other than foundations.
Choose the type of wood and wood-boards according the type of use: indoor or outdoor.
One should check if wood reserves are properly managed (and if alternative materials could help in preserving forests). The following institutions and organisations are specialised in forest management and preservation:
- CITES Convention on International Trade in Endangered Species of Wild Fauna and Flora
- ITTA International Tropical Timber Agreement
- PEFC Programme for the Endorsement of Forest Certification www.pefc.org
More information in the book "Timber", available for download from:
www.humanitariantimber.org
Wood as fuel: Still the most commonly used fuel in the world for cooking and heating. See our fuel saving stoves and heaters (item code HHEASTOHW…). Also keep in mind that traditionally processed charcoal retains only 20% of the original fuel content of the wood.
Specifications
|
Variety |
As per stated in contract. |
|
Dimensions |
As per stated sizes and total volume required. |
|
Tolerance |
Maximum 5mm of in width and height. |
|
|
Usable length to be minimum as stated in contract, longer by 50 to 100mm is recommended. |
|
Seasoning |
Dried to 20% maximum moisture content (Specify drying method and time). |
|
Treatment |
Treated against insects and termite in particular. Treated against mould. |
|
Grade |
Class I, II, III, IV, as per contract. |
|
|
International suppliers will supply to international standard construction grades. |
|
Serious damage to outer fibres caused by poor storage, transporting, etc. will result in rejection of the goods. |
|
If timber must be visually graded: |
|
Decay |
Timber is free from pests and rot |
|
Sloping grain |
1 in 8 |
|
Knots, sound |
1/3 dimension of face, max 10cm diameter. 1 per meter in length |
|
Knots, unsound |
1/4 dimension of face, max 7cm diameter. 1 per 3 meter in length |
|
Wane, want and sapwood |
1/3 sum of width and thickness |
|
Split |
Longest split, 100mm at each end |
|
Shake |
1/2 thickness |
|
Compression failure |
None |
|
Warp |
Bow, Cup, Spring and Twist: 1 cm in 3m |
|
Sweep/crook |
Pole does not deviate from middle axis |
|
Taper |
Not exceed 10mm per meter for poles |
|
Spiral grain |
No from ‘twisted’ trees |
Delivery (C.8)
|
Required Documentation |
Supplier |
|
Local |
National |
International |
|
Certificate of legality from national government |
YES |
YES |
YES |
|
Guarantee that no timber from the CITES list |
YES |
YES |
YES |
|
Timber travel document
|
YES |
YES |
YES |
|
Sawmill license
|
YES |
YES |
YES |
|
Proof of sustainability |
Preferable |
YES |
YES |
|
Phytosanitary certificate
|
NO |
YES |
YES |
|
Customs clearance documentation |
NO |
NO |
YES |
|
Documents relating to other national law |
Preferable |
YES |
YES |
|
Description of harvesting/logging process |
YES |
YES |
YES |
|
Description of seasoning and treatments used. |
YES |
YES |
YES |
|
Certification of quality by a national or international grading system. |
Preferable |
YES |
YES |
|
Phytosanitary certificate checklist |
|
Details of packing |
|
Botanical names of tree species and whether wood is softwood or hardwood |
|
Country where tree came from |
|
Serial numbers of phytosanitary certificates issued in the country of origin (import if timber is re-exported) |
|
Dimensions / weight of packaging articles plus volume of wood in cubic metres |
|
Name / number of boat or plane |
|
Wood treatment type (e.g. Chemical Pressure Impregnation) |
|
Name of chemical used |
|
Duration of treatment applied for effective treatment |
|
Dosage rate of chemical (number of grams per cubic meter) |
|
Date of treatment |
TREATMENT OF TIMBER:
The treatment should comply with safe, acceptable standards against insect, especially termite, and fungal attack, to the required Hazard level as per contract. Treatment to comply with any applicable health and safety standards. In addition, the supplier must guarantee in writing that the treatment is completely fit for its purpose i.e. it is safe for humans (adults, and children of all ages) in circumstances where the treatment will be used internally (including in bedrooms / sleeping areas), with possible prolonged direct skin contact with the wood, over a period of many years.
All treatments to be certified by third party audit scheme such as AgriQuality treatment programme or equivalent.
Supplier to specify name of treatment chemical and registration certification with parameters of penetration and retention as per applicable standards.