TWA Heavy Oil Preservative

From $47.00

TWA Heavy Oil Preservative

From $47.00

TWA HEAVY OIL PRESERVATIVE is a general-purpose oil-based timber preservative for exterior out of ground contact applications. It is an excellent treatment against fungal decay and is most suited for use for untreated hardwoods in applications like decks, fences, landscaping,
wharves, bridges and other engineering structures.

SKU: N/A Category:

Directions For Use


HOP can be applied by brush roller or spray. For exterior applications two coats are generally recommended with particular attention to endgrain
joints and interfaces (also see IN-GROUND PASTE). Clean up with mineral turpentine.

Surface Preparation

New timber should be reasonably well weathered before application. This is particularly important with naturally oily timbers such as Tallow Wood
and Jarrah. Dressed timbers, when new, should be allowed to weather for a few weeks prior to application. Thinning the product with mineral spirits or kerosene may also improve absorption and drying speed in these cases. For old timbers and remedial treatments it is essential that any decayed and weathered wood or old paint be removed prior to application.


Apply moderately as excess product will not absorb readily in most timbers.
Coverage will be generally 6-8 square metres per litre.

After Treatment

Timber coated with HP will Initially be a strong dark green colour. With hardwoods this colour will change to rich variable brown tones, particularly when exposed to strong sunlight. This is due to a reaction of the preservative with hemicellulose which is usually abundant in hardwoods.
Softwoods, with their lower hemicellulose content, tend to remain an olive green colour which may weather eventually to light brown. Colour
development is dependent on the type of timber and will be much less pronounced on heavily weathered surfaces. Drying time may vary
considerably with the moisture content of the timber and local drying conditions. With dry timber and fine warm weather drying will take 2-3 days. This may be considerably longer for the second coat or with unseasoned timber or in cool weather. If possible wait at least one week before applying additional coats. Absorption and performance of the product will generally be better on rough sawn rather than dressed timbers.

Recommendations and Re-Application

Generally, the product should be reapplied after 2-3 years. This may be shorter or longer depending on the severity of local conditions. The
preservative value of the product will persist long after much of the original colour has apparently weathered away. As the treatment is a penetrating
oil type, re-application is easy as the new coat can go directly over the old without additional preparation.


First Aid Instructions

If poisoning occurs, contact a doctor or Poison Information Centre (13 11 26).
Hold eyes open, flood with water for at least 15 minutes – see a doctor.
Remove contaminated clothing and wash skin thoroughly with soapy water.
Remove to fresh air.
If Swallowed
DO NOT induce vomiting. Give a glass of water to drink and transport to hospital.

Manufacturer Product Information Page

TWA Heavy Oil Preservative


Additional information

Weight N/A