Celcure FAQ's - Koppers Preserved Timber

 

1. What is Koppers Celcure®?
Celcure® timber preservative is a waterborne, alkaline copper quaternary preservative system developed to provide long-term protection of timber exposed in interior and exterior applications. The Celcure® preservative system is based on the well-established effectiveness of copper combined with an organic quaternary compound and is applied to timber by pressure treatment.

 

Celcure® treated timber is available for the following use classes: UC1 - UC3 Above ground, UC4 ground contact and fresh water contact. Celcure® products are not currently approved for saltwater immersion applications.

 

2. Is Celcure® treated timber code approved?
Celcure® treated timber, meets all major building code requirements. Installation must comply with the requirements of all applicable local and national building codes.

 

3. How are Celcure® preservatives applied?
Celcure® preservatives are applied in factory controlled applications to ensure suitable preservative retentions and protection.

 

4. Can Fixings and Fasteners can be used with Celcure® treated timber.
Yes, but always use fasteners and hardware in compliance with the manufacturers recommendations and the building codes for their intended use. Fasteners (and other metal products) for use with Celcure® preserved timber products include:

5. What are retentions or retention levels?
Retention levels refer to the amount of preservative retained in the timber following the treatment process. Retention levels can be different based on the timber preservative system used to pressure treat the timber product and its intended end use or use class (UC) (UC4 ground contact, (UC1 – UC3 above ground contact). It is important to purchase treated timber products for the intended exposure condition. Typically, timber products are treated for "above ground use" and "ground contact/fresh water immersion use.

 

6. Is maintenance required on pressure treated timber projects?
Nothing is "maintenance-free". Pressure treated timber products help protect timber from fungal decay and termite attack. However, moisture, sun, and outdoor conditions may cause the timber project to show signs of weathering.

Natural weathering such as raised grain, splitting, checking, twisting, warping, shrinkage, or swelling occurs in timber treated or untreated.

 

To help reduce the effects of natural weathering, the use of a clear water repellent coating or a semi-transparent water repellent coating product is recommended.

 

If you desire to apply a paint, stain, clear water repellent, or other finish to your preservative treated timber, we recommend following the manufacturer's instructions and label of the finishing product. Before you start, we recommend you apply the finishing product to a small exposed test area before completing the entire project to ensure it provides the intended result before proceeding.

 

7. Can I paint pressure treated timber?
Yes. If you desire to apply a paint, stain, clear water repellent, or other finish to your preservative treated timber, we recommend following the manufacturer's instructions and label of the finishing product.

Before you start, we recommend you apply the finishing product to a small exposed test area before completing the entire project to ensure it provides the intended result before proceeding.

 

8. How does mould affect pressure treated timber?
Mould occurring on pressure treated timber products is typically not an indication of fungal decay attack.

Mould growth can and does occur on the surface of many products, including untreated and treated timber, during prolonged surface exposure to excessive moisture conditions.

 

To remove mould from the treated timber surface, timber should be allowed to dry. Typically, mild soap and water can be used to remove remaining surface mould.

 

9. What is the best treatment for staining/sealing my deck?
Depending on the look you want to achieve you can use a clear water repellent coating or a semi-transparent water repellent coating product. If you desire to apply a paint, stain, clear water repellent or other finish to your preservative treated timber, we recommend following the manufacturer's instructions and label of the finishing product. Before you start, we recommend you apply the finishing product to a small exposed test area before completing the entire project to ensure it provides the intended result before proceeding.

10. How often do I have to apply a finish to treated timber?
Most water repellent coating manufacturers recommend an annual application. We recommend you follow the manufactures' instructions.

 

11. My deck has not kept its original pressure treated timber colour. How can I restore the appearance of the treated timber?
There are several pressure treated timber deck cleaning products on the market that are available and can be purchased from hardware stores or home centres. These cleaning products are typically referred to as cleaners, brighteners and restorers. Always follow the manufacturer's recommendations.

 

12. Can I use a pressure washer on pressure treated timber?
Yes, follow the pressure washer manufacturer's recommendations.

 

13. Can I use treated timber in my raised vegetable bed?
Celcure® treated timber products may be used to construct raised bed gardens. Celcure® treated timber products for raised bed gardens should be treated for ground contact Use Class (UC4).

 

Very small amounts of copper and quaternary will migrate out of Celcure® treated timber over time. If it is desirable to minimize the migration of copper or quat into the soil of a raised bed garden, we recommend that a suitable thin plastic material be used as a barrier between the Celcure® treated timber and the raised bed garden soil.

 

The use of a plastic barrier will also help keep the raised bed garden soil within the bed area. For proper drainage, the plastic material should not be used underneath the raised bed garden soil.

 

14. Is it safe to use treated timber in a picnic table or on countertops?
Celcure® pressure treated timber products can be used for outdoor picnic tables. We recommend that the picnic table be covered to prevent food from contacting the timber surface. It is not recommended that any treated timber product be used as a countertop. Do not put food directly in contact with treated timber.

 

15. Can I use treated timber in feed troughs for livestock?

Do not use preserved timber under circumstances where the preservative may become a component of food, animal feed, or beehives.

 

16. Can I use AC-500 in an aquatic environment?

If the timber is not in direct contact with the water, does not contain any aquatic life & is simply overhanging, then an AC-500 treatment timber is acceptable. If the water contains aquatic life, it's use is subject to the degree of overhang, the size of the aquatic environment and whether the water is captive & still (i.e. a pond or free flowing river). Given, the complexity, it is recommended that where there is aquatic life, you should not use AC-500 treated timber.