What does LOSP stand for?
Light organic solvent preservative (LOSP) is a waterproof timber treatment. LOSP may include synthetic pyrethroids, imidacloprid, azoles or copper naphthenates, which are all pesticides, but as it uses a solvent such as white spirit to contain the insecticides and fungicides, it is less hazardous than other timber treatments.
How is LOSP applied?
LOSP is applied by vacuum pressure impregnation. Because it is not water based the timber does not shrink, warp or expand.
What is the Hazard level?
Hazard level of timber treated with light organic solvent preservative: H3.
What is repelled by LOSP?
Moderate decay, borers and termites.
What are typical uses of timber treated with LOSP treatment?
LOSP is used outside, above the ground. LOSP treated timbers are not effective against soil-borne fungi, therefore they should not be used in the ground and cut ends should be properly sealed.
Can I paint my timber?
LOSP treated products release the carrier solvent after treatment, so it is essential before application of a paint system that an adequate period of release or “flash-off” occurs. The period of time can vary according to the time since treatment, how the product is wrapped and stored and of course weather conditions amongst other factors. An odour is not a reliable guide as this varies with the formulation. It is recommended that the timber is allowed to air for a minimum of 7 days after delivery, preferably in a weather protected situation. Don’t forget to reseal before the application of the paint system. Whether the timber product is painted before construction or painted after construction, it should be coated with an oil base (alkyd) primer, then after suitable drying, coated with an oil-based or acrylic/water based paint system. Acrylic primer may be able to be used refer to paint manufacturers recommendations Always refer to the paint manufacturer’s instructions.
Do I need to oil or coat treated timber?
Preservative treatment only protects the wood against attack by insects, termites and decay or rot. To keep the timber looking good, it should be coated with a paint, or stain or water repellent such as oil. Uncoated wood will still resist attack by insects or rot, but it will weather to a grey surface with time.