Applying the right amount of oil is essential in protecting your Cedar from the harsh New Zealand sun.

The purpose of applying oil is to seal the boards from moisture. And the only way you can seal the boards is to put enough oil into the deep pockets of the timber that the water will stop getting in.

If the pores of the timber are not filled with oil, they will accept whatever other liquid there is available, such as the rain or moisture in the air. This causes the boards to swell and contract, absorbing and releasing moisture.

The summer heat will then dry the surface of the timber and as the surface tension gets tighter, the boards will begin to cup.

Follow the Manufacturers Guidelines

For the purposes of this article, we will look at the manufacturer’s guidelines for Wood-X.

Coverage of Wood-X penetrating wood oils is dependent on surface condition, timber type, air temperature and other factors. The following is an approximate, typical guide.

Tinted oils and stains are two very different products – each with unique compositions, application requirements, and long-term maintenance needs – but the names are often used interchangeably.

Even amongst building professionals, there is a lot of confusion around different Cedar treatments, and which is best for the long-term protection of Cedar in different situations.

In fairness, the difference is not always obvious, and much of the confusion comes from the terminology used by manufacturers in the past.

This article aims to set the record straight, and show why it’s beneficial – both for your Cedar and for your wallet – to know the difference between Cedar treatments.

Let’s start by defining what exactly is an oil and a stain.

What is a Penetrating Oil?

Penetrating oil is designed to migrate into the timber and waterproof it from the inside, protecting against movement from the wetting and drying process, but it offers no UV protection.

We do not recommend using clear oil on Cedar cladding as there is no UV protection.

When a tint is added to a clear oil base, it becomes a tinted oil.

The tinted oil has all the waterproofing benefits of clear oil, but the tint now protects the timber against UV, like a sunblock, and it can be applied with a range of different colours.

What is a Stain?

Traditional stains use a solvent to emulsify the oil and are typically a brown-red colour, prevalent on homes built before the 2000s.

Solvent based stains are still available, but they are being phased out in favour of water-borne stains, which are more environmentally friendly, and come in a range of colours.

Water-borne stains emulsify the oil in water. When applied to the surface, the water evaporates leaving behind the oil to migrate, to a degree, into the surface of the timber.

Stains do not penetrate deeply into the timber, unlike oil, and are designed to erode from the surface over time. Once the stain has been broken down by the UV, any remaining stain will need to be washed or sanded away before applying new stain.

Where Does the Confusion Lie?

Stains and tinted oils are the most common source of confusion when talking with Cedar homeowners.

People think of a stain as something they brush on and the stain then soaks into the timber. This is true, but a stain will only soak into the timber marginally compared to a penetrating oil.

If you pour tinted oil onto a white sheet, it’s going to change the colour of the sheet without changing the texture, essentially staining the fabric.

If you do the same with a traditional stain, which is actually like a very thin paint, it’s going to leave a coating on the sheet. It will change the colour, but only because there is a coating on the surface. It’s not actually staining the fabric.

By this rationale, a stain is not actually a stain, but it’s been called a stain for so many years that the name has stuck.

This may seem like splitting hairs, but knowing which product is right for your Cedar has a significant impact on how your Cedar needs to be maintained.

Why Does This Matter

If you know what treatment is on your Cedar, you can formulate the right maintenance strategy for your home – and potentially save yourself money, and heartache.

Here are a few practical examples:

• Existing Cedar Homes

If you already have a Cedar home, this means you can use the same treatment as before for the best colour matching and application; while avoiding generic products that do not perform as well, or incompatible treatments, such as applying a water-borne stain over an oil.

• New Cedar Homes

If you are building or buying a new Cedar home, a stain is often applied as it requires little upkeep for the first 5-10 years, but eventually the sun will dry out the timber and you might have to use a Cedar professional for maintenance or remedial work.

• Cost and Upkeep

Different treatments have different costs. Oil migrates deep into the timber, but doesn’t last on the surface as long as a stain and needs more regular upkeep. Stain lasts longer, but once it erodes, it needs to be removed evenly before recoating, or you end up with an uneven finish.

• Cedar Orientation

Areas in the shade require less maintenance than sun-exposed areas, making stain more suitable in some circumstances. And if you have an area of Cedar up high, the cost of scaffolding might be prohibitive for regular application of oil and a stain might make more sense.

All these potential complications can be eased by knowing what treatment has been used on your Cedar, and what treatment is best for different situations.

Final Thoughts

We are not saying that one product is better than the other, but by understanding what treatment is on your Cedar, you can make better decisions about how it needs to be protected.

If you are unsure, get in touch with our team and a Cedar expert will come out to your house to assess your cladding.

Mark has been in the business for over 30 years and has seen a lot of Cedar products come and go. The products recommended here are based on his personal experience maintaining thousands of Cedar homes across the country.

These are the products we actively use today, or have used in the past, and all have been tried and tested across a range of locations and conditions.

If the product you are considering isn’t mentioned below, that doesn’t mean it’s unsuitable, only that we don’t have enough experience with the product to recommend it either way.

Always follow the manufacturers guidelines and choose the best Cedar product for your specific circumstances.

Lastly, if your Cedar has already been treated with a specific product and is still in good condition, it’s a good rule of thumb to use the same product for the best colour matching and application. If the product is starting to fail, look at the best solution for the timber regardless of what was used previously.

Best Cedar Cleaning Products

Preparing Cedar before applying an oil or stain is the key to achieving a smooth and consistent finish.

Over time, organic matter such as dust, moss and lichen will build up on the Cedar. As oils and stains are semi-transparent/translucent, any product or organic matter left on the surface will show up and look unsightly.

Which cleaning product you use depends on the current state of your Cedar.

• Hit The Deck

Cedar that has no oil or stain on the surface will only require a gentle wash using an oxy cleaner or percarbonate solution to kill off any built-up organic matter. Hit The Deck by Wet & Forget works very well and doesn’t contain any bleaches or chlorine.

• Dryden LiquidTimberClean

If your Cedar has been affected by the sun and started to age, you may need to brighten it back up. Dryden LiquidTimberClean is an oxalic acid-based cleaner that is effective at lightening stains and brightening timber. Be careful using this product around windows and joinery as it can tarnish the surface if not rinsed properly.

• Resene Timber and Deck Wash

For general cleaning, Resene Timber and Deck Wash is very effective for cleaning hardwood and softwood timber surfaces. This wash only has a small amount of bleach and is effective at killing off anything organic. An excellent product, we use it all the time.

• And avoid…

We do not recommend any products that contain a heavy solution of sodium hypochlorite, commonly known as bleach. This often comes with the benefits of “spray and walk away” or “done in 30 seconds”. It will certainly clean the Cedar and kill off anything that’s on the surface, but it can damage the cellular structure of the timber.

Quick Note About Stains

Stains are like white paint. You can buy white paint from 20 different paint manufacturers and each one will tell you why theirs is the best.

Which stain you use is much less important than when and where you use it.

Stains perform best out of the harsh UV, on areas sheltered by trees and other buildings, south-facing, or under soffits.

If used on areas exposed to the sun, they will eventually break down. If a stain cracks, water will get in behind and delaminate the stain, lifting it from the surface.

When stains fail, it takes a lot of work to make the stained surface look good, even more than with oil. Just remember, when choosing your coating, the sun will ALWAYS win. Make sure the stain is out of the sun, and you should be fine.

Best Cedar Stains

• Resene Woodsman Waterborne Oil Stain

Resene Woodsman Waterborne Oil Stain is our stain of choice. This stain is a penetrating water-borne wood oil stain that is designed to erode, rather than form a film on the surface, which is what you want. As the stain is very thin, it gives a chance for the oil to get into the timber. This stain has been around for 15+ years and we have a lot of confidence in the product.

• Cabbots stain

Cabbots stain, by Dulux, is another product we regularly use. Cabbots is an excellent stain, with the slight reservation that this is a film-forming product, and it can get brittle if over applied.

• Coating Remover Sea to Sky by Resene

If you need to remove a previous stain before application, use a coating remover that uses organic or citrus based compounds. Avoid methylene chloride products, which are very aggressive.

Coating Remover Sea to Sky by Resene is an organic stripping compound that contains no harsh chemicals, and is very effective at removing paints, coatings and residues.

• Be careful, it’s a messy job…

Mask or cover the areas adjacent to the areas you are working on and make sure you get all the product out of the timber. Use a water blaster at the correct pressure to remove any latent product sitting on the timber’s surface.

Quick Note About Oils

Unlike stains, not all oils are made equally. As oil is the base ingredient in these products, the quality of the oil can affect the speed of penetration and dry to touch time, and the final look and feel.

Choose an oil from a reputable manufacturer that has been formulated for the specific conditions in New Zealand.

Other factors to consider include the biocide package (to keep away nasties), available colour range and the degree of transparency. depending on how much you want the Cedar to come through.

All that said, it’s always better to apply oil to your Cedar than not. You are looking to protect the surface of the timber from the harsh sun, and anything is better than nothing.

Best Cedar Oils

There are 3 different products we can recommend. Before getting to our top pick, we need to cover a little history to better understand the evolution of Cedar oil products.

• CD50

CD50 (now known as CUTEK Extreme CD50) is the original Cedar oil and has been around for 40 or 50 years. The product has since been bought by an Australian company and reformulated for the Australian market. We don’t use this product much as the alternatives listed below are better suited for New Zealand conditions. Regardless, this is a quality penetrating oil with a long and storied history.

• Dryden WoodOil

Dryden WoodOil is owned by Dulux and specially designed for our conditions. 20 years ago, CD50 was sold off and the manufacturers reformulated Dryden WoodOil from the old CD50 chemical makeup. Dryden WoodOil is water-repellent, non-filming, and a true migrating oil that gets deep into the timber. We regularly use this product and can recommend it without hesitation.

• Wood-X

Wood-X is our top pick and the oil we recommend for most of our customers. Wood-X is made by Resene and specifically formulated for New Zealand conditions. Wood-X is a non-film forming, viscous mineral oil that is designed to penetrate exterior hardwood timbers and improve dimensional stability. 

Wood-X also has an excellent biocide package, high quality and proven tints (colour tones), and uses high grade oil content that speeds its penetration and ‘dry to touch’ time.

Full disclosure: TimberTech helped to develop Wood-X and Mark has a small shareholding in the business. We are proud of our association with Wood-X and wouldn’t recommend it if it wasn’t the absolute best product for our customers.

Need Help or Advice?

If you have any questions about the products we covered, please get in touch with our team. We are more than happy to give advice and point you in the right direction.

Let’s get to the point. Is DIY Cedar maintenance possible?

Absolutely. Furthermore, the process is relatively straightforward.

Cedar maintenance is all about protecting the timber from the elements, most importantly, the harsh New Zealand sun. If you have a long, hot summer, the natural oils in the boards will be sucked out by the sun.

Your job is to replace the oil that the sun is extracting. Without oil replenishment, the boards will dry out over time and begin cupping.

A general DIY Cedar maintenance plan would involve soft washing your house once every few years and applying a coat of oil to sun-exposed faces every 2-3 summers.

Seems straightforward, right?

So is changing the oil on your car, but very few people have the time or are willing to get their hands dirty. The same goes for Cedar.

Here are some factors to consider before attempting DIY maintenance.

1. Convenience

We have a customer in Northland who is 83 years old and had previously maintained the Cedar on his family home for decades – and did a great job of it. Now that he can’t get up the ladder like he used to, he came to us for help.

Anybody can learn how to maintain their own Cedar, but not everybody has the inclination. Maintaining Cedar is physically demanding, often working at heights, using bulky equipment, in a wet and mucky environment.

Hiring a professional means you don’t have to worry about anything. They will bring all their own equipment, have experience working at heights and clean up after themselves, leaving nothing but a beautifully maintained house.

2. Property Access

Accessing the different areas of your house can be tricky, and potentially dangerous.

Even on a flat property, there are always parts of a house that are difficult to reach. The job gets even more complicated if the ground is uneven.

Double story house can be quite daunting. Some houses require scaffolding, but most houses can be accessed with a ladder.

If you are not comfortable working on a ladder, or the ground around your house is uneven, it is usually safer to hire a professional who is experienced working at heights.

If your house does require scaffolding, a professional Cedar maintenance company will often have their own scaffolding and manage the whole process, saving you time, headaches and money.

3. Risk of Damaging the Cedar

The surface of a Cedar weatherboard can be easily damaged. The water blaster should be set at a low pressure and moved across the boards in a steady motion without pausing.

Water blasting at a high pressure can strip away too much of the soft tissue in the timber, leaving it streaky and unsightly.

This is often when we get called, only now the customer is paying for remedial work to restore the damage rather than just maintenance.

Your home is usually your most valuable investment. By hiring a professional, you are removing the risk of damaging the timber and ultimately, adding value to your investment.

4. Preparing the Cedar for application

Cleaning and preparing the Cedar is the most important part of getting a satisfactory finish.

People can be so scared of damaging the timber, that they use a water pressure that is too low or don’t scrub sufficiently to properly clean the Cedar.

If you do not remove all the built-up organic matter, whatever you put on the surface will then be compromised.

To prepare your Cedar with a water blaster, make sure you wash it at the right pressure, or scrub the boards with an appropriate brush, making sure the boards are free of any timber fibres, oxidised tint, dirt, mould, lichen and moss.

Once all that is gone, you need to make sure any stain on the boards is evenly removed. You don’t want the boards under the soffit left a different colour.

5. Consistent application of the product

Applying a stain is simple, you move the brush from one side to the other keeping an even coverage and a wet edge.

But getting an even finish across the boards takes time and practice. If the stain dries before you finish, there will be lines in it.

We have also seen DIY oiling attempts that only go 3/4 of the way up the wall because they couldn’t reach any higher, or thought the Cedar was protected by the soffits of the house.

Trying to blend that in after the event is very difficult and always ends up costing more in the long run.

Thinking Twice About DIY?

Anyone can learn how to maintain their Cedar, but it probably looks easier than it is and is fraught with little problems that when added together, become bigger issues.

If you require expert advice, call us on 0800 298 298. Our friendly team is always ready to help.