Balau vs CCA Treated Wooden Deck Durban

I often get asked about using balau as a substructure in a wooden deck. There are various pros and cons of using balau as a substructure in your wooden deck so I thought I would jot it down and in future I can direct clients here who want the ins and outs of using balau as a structure for your wooden deck.

Balau is a very good, hardy and durable wood to use in outdoor wooden decks and other outdoor projects. It contains toxins that limit insects eating it and it is high in resins and oils which naturally repels water and limits rot. All wood will eventually rot. It is just that some will rot quicker as they are less dense and less oily which means they will absorb water more easily, which remains in the wood, causing fungus to grow which breaks down the fibres in the wood and is commonly called rot. This is a simplified explanation but I think it delivers the message accurately. Water doesn’t cause rot. Fungus, as a result of water and sunlight, causes rot.

Balau therefore will rot and I have started documenting some pics of rotten joists that I have come across in my repair work of wooden decks. It may take 15 years for this rot to start but it will happen and when it does repair work can run into thousands if not a complete deck rebuild. Joists are often difficult to access whereas deck boards are not.

On the other hand a piece of wood that has been chemically treated to prevent, or limit rot, will last a lot longer and a pre determined life span can be calculated.

CCA Treatment is a process of pressure treating SA pine. A vacuum is created in a chamber that contains the pine and a solution of copper, chrome and arsenate is introduced which then takes up the void created by the vacuum sucking the solution into the cells. The copper prevents fungus growing which in turn prevents rot, the arsenate keeps the insects away and the chrome binds the two to the wood so that I doesn’t leach out.

Balau is too hard and dense to treat. Pine is a commercially grown timber in South Africa which is inexpensive and very suitable for treatment as it is soft and takes up the solution of CCA successfully. There are various different Hazard Classification or H classifications. Basically H2 is good for indoors (roof trusses etc.) H3 for outdoors exposed to the elements, H4 for in constant contact with wet soil. H5 for submersion in fresh water and H6 for submersion in salt water. A correctly treated piece of pine to H3 will, as per SAWPA guidelines, last in excess of 50 years which is pretty impressive in comparison to a piece of balau that comes with no fixed life expectancy. A poor quality piece of balau may start to fail within 5 years whereas a good quality piece may only start in 15 years. Most of the pics I have documented here are of decks that range in age from 8 years to 15 years. But generally speaking I have found some rot setting in all the decks of 15 years or older.

S5 (SABS Structural grade) Pine is considerably cheaper than balau structural timber. So from an economic point of view it makes sense to use pine in place of other woods wherever possible.

One might now ask why is pine not used on the surface of a deck? Why is balau preferred?

Balau is a very stable wood and therefore expands and contracts less than pine. It is about twice as dense, knot free and doesn’t twist and warp as easily. Pine is soft and with the sun beating on the deck it will tend to crack, twist and warp more easily. To use pine as a deck board one needs to use a 38mm board as opposed to a 19mm board in balau (twice as much wood). Also pine deck boards are normally manufactured from S7 as opposed to S5. S7 refers to the number of knots per square inch (or centimetre) and is therefore a lot more expensive than S5. The cost of pine deck boards is in fact a few rand more per square metre than balau. Hence the reason to use correctly treated CCA pine as a substructure and balau as deck boards. Again pine doesn’t work well in balustrades because twice as much wood needs to be used at S7 grade.

For a free no obligation quote on your sun deck, pool deck, balustrades, pergolas etc., please call us on 082 496 5444 or use the contact us form below.

CCA Treated Substructures in Wooden Sundecks – Durban

Wooden sundecks Durban North

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As I’ve mentioned in previous articles we use a H3 CCA treated pine substructure which the suppliers offer a 50 year guarantee on. In order to activate that guarantee we need to adhere to best practices and there are a few things that we need to do, and document by way of pics. 

Although all decks we build are built according to best practices, when applying for a guarantee we need to document it. So if you require a guarantee please let us know beforehand so we can collect all the documents we need to process it. These include charge sheets and retention records from the treatment plant to ensure that the chemicals used in the treatment process penetrated the timber properly. The charge sheets also document all sorts of things such as how much solution was added to the chamber, how much wood was in the chamber and how much solution much was left over. From this one can work out what the penetration was and can be verified through the retention records.

When the wood is treated it is placed in a chamber and all the air is sucked out to create a vacuum. Solution is then added to the chamber which now takes up the void or vacuum and the solution is sucked into the timber. They call this pressure treatment.

Wooden decks Durban

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CCA is an abbreviation for Chromated Copper Arsenate. The copper stops fungus growing on the wood, which in turn causes the fibres of the wood to break down and rot. The arsenate stops insects from eating it and the chrome binds the two so that they don’t leach out of the wood. There are different hazard classes of CCA treated timber. For a full explanation you can visit http://www.sawpa.co.za (South African Wood Preservers Association).

Once this pine has been treated it can now get wet without the fear of it rotting because the fungus cannot grow. It is not water that causes rot, but rather fungus. The water allows the fungus to grow which breaks down the fibres of the wood which causes rot. So now your wood can get wet without rotting.

When the wood is treated, this CCA solution they use penetrates the timber based on the pressure they use and the time it remains in the chamber. The longer the time, the greater the pressure and the stronger the solution, the higher the hazard class and more resistant it is to rot and insect infestation. So timber being used outdoors subject to weathering (rain and sun) needs to be of a higher Hazard Class than timber being used in your roof where it is protected from rain to a large degree.

The depth of the penetration is subject to the density of the timber (pine vs. saligna or gum), and the time in the chamber. These retention records mentioned above are obtained from coring a section of the timber on each batch to ensure that the solution penetrated the timber properly. The charge sheets will outline how long the timber was in the chamber, the strength of the solution etc.

Wooden deck guarantee

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So once all these documents have been collated, one can apply for a guarantee from the suppliers of the solution used in the treatment process.

One last criterion is that where we cut a piece of timber we need to treat the end grain with an end sealer approved by the supplier. This is because the solution used in the treatment process does not penetrate all the way through the timber. Depending on the density of the wood it will penetrate about 16mm into the timber. With pine, as opposed to saligna, it will obviously penetrate further as the timber is softer. Timber such as balau cannot be successfully treated as it is too dense. However it rarely needs to be treated as it is naturally resistant to insect infestation and rot due to the resins and oils naturally found in the wood.

By following the manufacturers and SAWPA’s guidelines one can successfully use treated pine as suitable outdoor timber for decking.

The pictures alongside show where we have used an approved end sealer to treat the timber on all cut ends.

For a free no obligation quote on your decking and other outdoor requirements please contact us on 082 496 5444 or use the contact form below.

Wooden Decks Durban – Bluff

Wooden decks Durban

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This wooden deck in Durban was the second phase of a job we started at the beginning of the year. We were originally asked to build a deck off the main bedroom. First we had to remove the aluminium window and install an aluminium sliding door. I always suggest that clients do this first so that we can build our wooden decks perfectly flush to the new opening.

We had various obstacles to overcome. There was a septic tank that we were building on top of so we had to leave sufficient space and a large enough trap door to access all three tanks. We built one large trap door so that the whole thing could be taken off to access these tanks. During our build a new soak away had to be built as the old one had packed up.

With all of this out-of-the-way, we could continue with phase two which was to complete the main deck with two steps off the front edge leading to the garden and a new second deck in front of the sliding doors to the lounge. This second deck had a corner step similar to the other deck.

Wooden decks Durban

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These steps were the full length of the deck and had closed risers and treads. In order to build one of these you must basically build a second substructure in the same way as you build the deck substructure in order to span your deck boards across them. So each tread has two beams and joists and is then clad with deck boards. I can clearly remember building our first one which took ages because we tried to build each joist individually. We’ve since learned that with smaller structures one can build a frame and then pull it into position and attach it to the main structure and then clad it. Much quicker, much easier and a lot more accurate.

This was our final job for 2013 and we lost one day to rain which set us back a day and we had to spill over into the weekend. We had originally planned to finish on the Friday, but we had to come back on Saturday morning to seal it.

The original deck we built earlier on in the year had greyed already from the sun so we had to sand it quite a bit to get it back to its original colour for the two to match.
Most of our decks this year have been built using an H3 CCA treated pine substructure. We are able to offer a 50 year guarantee from the supplier for the H3 treated timber and a 30 year guarantee for the H4 treated timber. The cost

Wooden decks Durban

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difference between balau and CCA pine is huge so we can keep our rates down to our clients and the H3 CCA pine will actually outlast the balau substructure. We still use balau as deck boards and balustrades simply because it is a lot more attractive and more stable so reduces cupping, bowing and checking. In the substructure, because of the size of the timber it is not as important to limit cupping and bowing.

For a free no obligation quote on your wooden decks, pergolas, walkways, balustrades and other outdoor timber construction please contact us on 082 496 5444 or use the contact us form below.

Wooden Deck Installed in Queensburgh, Durban

Wooden deck installer Durban

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This wooden deck we are installing is almost complete. The pics alongside are work in progress pics. I’ll update it with some others once we are done and you can then get the full feel of the deck. It has been an interesting installation as there are effectively three sections to it and the whole job incorporates three different methods of installing a wooden deck.

The first section is a deck around the pool measuring 1.2m off the side of the pool. The slasto that was there had quite a steep fall from the edge of the pool to the soil to allow water to run away from the pool instead of in to it. We used 38 x 114 joists but had to cut them in a wedge shape to allow them to be level on top but still remain in contact with the slasto as much as possible. There is an easier way of doing this by using 38 x 38 batons with a foot on the side, farthest from the pool, so that the baton remains level on top. This would of course result in a large gap beneath the baton. Being only 38mm in thickness the baton would break as a load is placed on top of it. So one would need to pack the underside of this baton with a suitable material. In the past we have used structural grout simply because of its strength and usability. It is fairly easy to use as it is cementious based. You simply mix it with water and pack the gap. It dries extremely hard, harder than cement, and contains small fibres in it which give it its strength. Both ways are structurally sound, but cutting wedge-shaped joists takes time and they inevitably need to be shimmed to get to a perfect level across all joists. Packing them is easier and just as strong. So next time I will revert to the old tried and tested method of packing them to save time.

We ran our deck boards parallel to the pool on all fours sides, rather than running them all in the same direction. The method we used in this deck is of course the better method. It looks neater and also keeps more water from the pool away from the end grain of the deck boards. Water is absorbed by wood largely through the end grain so this method will result in less rot than running them all the same way where two sides will have end grain facing the pool. However, and a big however, this method is tricky in that if the pool is not perfectly square, the corners of the deck will not run out from the pool at 45°. If a deck board is cut at say 40°, the other deck board that will meet it on that corner will need to be cut at an angle other than 40° if the deck is not square as a result of the pool not being square. And herein lies the problem. The cut ends of each deck board will not be the same

Wooden deck installer Durban

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length and will not meet up nicely resulting in a stepped joint. Hence the deck MUST be built square regardless of how square the pool is. This brings with it another problem in that it will mean that two ends will overhang the pool and two ends will be flush with the edge of the pool. If the pool is only slightly out of square, then it is not a problem because it won’t be seen. However if the pool is far out of square, then the overhang on the two sides becomes too big. If this is the case then opt for deck boards running all the same way or a gap filler must be placed between the join, so that the eye cannot pick up the difference in lengths of cut ends.

There was small walkway of 1.3m wide by about 4.5m long joining this pool deck to the other deck pictured alongside. There was a small step up to this deck which was enclosed with a balustrade.

So three different style decking systems were used which made it very interesting. One was a baton system on a slasto substrate, the other was a frame system as the walkway and the third was a joist and beam system which was suspended about 2m up.

Tomorrow we will continue sanding and then seal.

For a free no obligation quote, please call us on 082 496 5444, or use the form below. If you call please let me know you found my blog so I can track my marketing.

Wooden Deck Built with Guarantee in Durban

Wooden deck guarantee

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As mentioned in some of my other articles we started offering supplier guarantees on our H3 CCA Treated pine substructures. These guarantees can run for up to 50 years from the date of installation. They are guaranteed by the manufacturer of the chemicals used in the treatment process and are underwritten by one of the large insurance companies. Provided certain building techniques are adhered to and the company treating the timber has treated it correctly, the manufacturer of the chemicals is willing to guarantee the timber against various forms of rot and various types of insect infestation for up to 50 years.

One of the conditions is that the end-user, being you the client, needs to register the build with the manufacturer within 60 days of completion of the build. The registering of the build needs to be done in a certain format and details such as when the timber was purchased, where it was purchased from, ERF number etc. needs to be submitted to them together with proof, in the form of photographs, of the building methods we used whilst building the wooden deck.

We need to treat the cut ends of the timber with an approved end sealer, we need to ensure that we are using H3 for timber above ground and H4 for timber in ground or in constant contact with wet soil and we have to show that we have planted our posts according to the recommended method.

Wooden deck guarantee

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We at The Wood Joint offer to facilitate this process for you, for a small admin fee, so that you may activate the guarantee with them. We take pictures of what we are doing to prove that we have used end sealer and adhered to their criteria. Once the build is finished we compile the report that will be sent to them, by you, to register the build and activate you guarantee. We can also assist in submitting it on your behalf.

In the pictures alongside you can see the end sealer we are using which is a diluted version of the same chemical that is used in the treatment process. This applies to all cut ends and drilled holes. The greenish colour is due to the copper in the solution which prevents algae growing on the timber which can cause rot.

We also take pictures of us planting the posts or poles so that it is clear we have planted them correctly. When one plants a post, it should always be placed on top of soil and then concrete placed around the post. If you wish to place it on top of concrete than that concrete should be allowed to set completely before placing the post and setting it in concrete. This is to allow any water that does get into the post to escape through the bottom of the post. If a post is set on top of wet concrete it will slow the escape of water through the pole and this will speed up the rotting process from within the posts. I’m sure you’ve seen some gum poles that have rotted from the inside out. This is because they have probably been set on top of wet concrete.

Wooden deck guarantee

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We also take pictures of the red SABS / SANS stamps on the timber so that it can be proved that the correct Hazard Level was used for the correct application, H3 for above ground and H4 for in the ground.

Both SABS and the company manufacturing the chemicals regularly, and unannounced, check on them and run test to ensure that their timber is being treated correctly. Pine cannot be treated in the same chamber as saligna (poles) for instance as the absorption rates of each timber are different. The timber needs to be treated at a certain pressure and the solution needs to be of a certain strength to arrive at the different H levels. This is tested by coring a section of the timber out, after treatment, and measuring the amount of timber the chemical has penetrated. They also use a dye to determine if the solution was of the correct strength. So it is important that this CCA treated timber is purchased from a reputable supplier.

Over and above this info we need to report on where the timber was purchased, when it was purchased, who treated it and so on. With all this information on hand, you the client, can register your build with the manufacturer and be rest assured that you substructure is safe for 50 years.

For a free no obligation quote on your wooden decking needs, please contact us on 082 496 5444 or use Wooden deck guarantee

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Sealing a Wooden Sundeck by The Wood Joint – Durban

Sealing a wooden sundeck can be a time-consuming task. One needs to ensure that the sealer gets in between the gap on the deckboards so as to seal both edges of each deckboard. Balustrades can also be very time-consuming as there are many corners and tight gaps to get in to.

We use Timberlife Satin Wood Base 28 which is oil based and very viscous. It has zero wax content so that nothing dries on the surface of the timber making future maintenance easy and very cost-effective. You simply clean and re-apply. No more sanding.

One way is to paint it on using a brush. Another is to use a sponge to rub it on. And yet another is to spray it on. Each method of application has its pros and cons. I’ll list each one here: –

Brushing it on

  • Very time-consuming
  • The brush tends to flick the sealer because it so viscous so when brushing up towards the wall one needs to ensure it doesn’t flick on the wall
  • Fairly accurate as you can get the sealer where you want it

Sponging it on

  • Quite messy so wear gloves
  • No flicking but lots of dripping as the sponge gets squeezed. Use plastic beneath if you don’t want it to spoil the paving, but it is ok if it lands on the deck as you will sponge that too pretty soon
  • Fairly accurate and much quicker than brushing
  • You may need to touch up with a brush in the corners
  • Can’t get successfully into the gaps between deckboards
  • You can use a sponge roller for the surface

Spraying

  • Very messy so mask the walls or use a piece of cardboard to protect the wall. Have thinners or turps on hand to clean it off the wall quickly if it gets on the wall. If the wall is PVA, be very careful, but it cleans off quite easily from acrylic paints and windows
  • Watch the wind, it can cause havoc
  • Penetrates everywhere
  • Use a garden sprayer on the finest setting it has

So there are many ways to seal your wooden deck if using a viscous sealer such as Timber Life Satin Wood Base 28 or Woodoc Deck Dressing. Use a combination of them and you will have your deck sealed in no time. Be careful of spraying though. Use lots of plastic, watch the pool, watch the wind. But even with these few pitfalls, it is much, much faster than brushing. Watch the video above of us spraying a deck. For a free no obligation quote, call us on 082 496 5444 or use the form below.

Deck Refurbishments

Deck refurbishment

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I have done quite a few deck refurbishment jobs and as mentioned in a previous article it is work I would rather stay away from. However, especially in the early days, it was necessary to do these jobs to keep paying the bills. Also it has provided me with a solid understanding of what not to do when finishing or sealing a deck. Also it has allowed me to see other construction methods of other deck builders first hand. Because these decks are relatively old one can see how a certain technique has behaved over time. But sometimes it is better to leave them alone, as I have done recently, because it can be like opening a can of worms.

The first thing to consider when sealing a new deck is to assume that you will be the one who has to refurbish it when it comes to refurbishing. This way you will probably apply the best finish to it so that future maintenance jobs are easy. The article on deck finishes covers in more detail what types of finishes are available and their pros and cons. When refurbishing one needs to first establish if there is structural timber that needs to be replaced. Sometimes it can be difficult to see if this is needed until deckboards are lifted. We did a job in La Lucia where we simply replaced deckboards and once we took the deckboards off we noticed that some of the joists had been eaten by insects and rotted. Although it is unusual for balau to be attacked by insects it can happen in the sap wood or if the tree was felled while it was still young. As a client and a contractor it is best to know exactly what state all the timber is in before the quote is accepted because no-one wants to find that once they lift the first deckboard the joists are so bad that new deckboards cannot be re-attached to them. So get underneath the deck, take a screw driver and poke around and see is there is rot or degradation.

Deck refurbishment

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Rotten deckboards themselves are quite easy to pick up as they will normally be visible from the top and they will normally start on one end where the water has been absorbed by the end grain. As mentioned in other articles, water is absorbed by wood through the end grain largely and very little is absorbed through face or side grain. As such the wood will rot from the ends first. If a rotten deckboard is found rather replace the entire length of that deckboard as chances are it will have started rotting all the way along. Be careful to know what deckboards have been used. A 19 x 68 deckboards is so close to a 21 x 72 that with the naked eye one might miss it. But looking at it carefully you will see it is both thicker and wider (and more expensive). Measure it to make sure.

Balustrades can sometimes rot too but normally only where water tends to collect. Screw holes left open and not filled with epoxy are also areas where the boards can rot more quickly. Some decks are not worth trying to repair. I’ve seen decks with posts that have rotted off and beams and joists that have rotted. It is not worth trying to patch that as eventually the whole deck will need to be replaced. The cost of this will exceed building a new deck. Pine decks tend to rot more easily especially if they have been built using H2 CCA Treated pine. A separate article will run through the different type of CCA pine and which ones are suitable for which application.

Use the search bar on the top right to search for other related articles or see below.  For a free no obligation quote on refurbishing your deck please call us on 082 496 5444 or use the form below.

Reducing rot in wooden sun decks

preventing rot in wooden decks

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This article will focus solely on reducing rot in wooden sun decks rather than a specific article on a job we have completed.
One of the first questions that are asked when planning to build a wooden deck is that of maintenance. Being wood, the deck will always be susceptible to rot and insect infestation, but with the proper care this can be reduced to the absolute minimum and can compare favourably, if not better, to using other materials such as composites, concrete and tiles. Let’s face it when it comes to aesthetics and warmth wood is best, but often people opt for other materials simply because there is a belief that they are easier to maintain and will cost less in the long run.

Rot is caused by a break down in the fibres of the wood. A breakdown in the fibres of the wood is caused by algae being allowed to grow on the timber which in turn is caused by water. Water therefore does not directly cause rot. A piece of wood can live in water all its life and not rot, but if it is not cared for properly then it will cause algae to grow and ultimately rot. CCA Treated timber of course eliminates this because it contains copper which prevents algae from growing. However it is only possible to CCA treat certain timbers such as pine and to a degree Saligna because of the differing densities of the woods. Pine is soft and balau is hard. CCA treatment is done through pressure treating (vacuum) and it is therefore impossible to CCA treat balau as it is too hard for the solution to penetrate the timber.

preventing rot in wooden decks

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So how does one reduce the chances of balau rotting? Well first of all balau is naturally resistant to rot because it is twice as dense and twice as hard as pine for instance so the water doesn’t penetrate it as easily. Also it contains natural oils and resins which repel water. So it will rot, but it will take longer than other timbers.

A piece of wood, any wood, takes in water largely through the end grain. Very little water is absorbed through the face or side grain. Think of it as a bunch of straws. When the straws get wet on the ends they can take up water, but they can’t take up water through the sides.

So the important areas of your deckboard is of course the ends, or end grain. Where a deck board is cut, there is not much that can be done to stop water ingression except to seal it with a suitable water-repellent sealer after or during installation. When a deckboard comes from the timber yard it is often closed off on the ends with wax. However that board needs to be cut in order to fit into the deck so one end will always be wax free. Also it is not advisable to leave that wax on. In the hot sun the wax starts to melt and leaves unsightly marks on the joins. So it is best to cut the wax off before installation. That leaves two ends exposed which now need to be sealed off as best as possible using sealer. Apply it liberally to the ends and make sure they are re-sealed during maintenance intervals.

The other area that is vulnerable is where the screw hole is drilled through the deckboard to attach to the joist. This leaves a hole where water can penetrate the end grain on two sides. What compounds this problem is that the screw is normally counter sunk which allows water to collect in the hole and be absorbed up and down the end grain. Some deck builders use a stop bit to insert the screw whereby the screw head stops at the surface of the deck. I don’t however use this method for two reasons. Firstly the screw is now not tight up against the bottom of the counter sunk hole so the board may work itself loose over the years. Secondly, there is still a small gap around the screw head for water to get into and move along the end grain. And trust me water will find that hole. You will often see deckboards that have started rotting at the screw holes. Now you know why.

Instead I counter sink the screw hole about 5mm, insert the screw and tighten it until it is tight right up against the bottom of the hole leaving the screw head counter sunk a few millimetres. I then take a clear epoxy, mixed with the sawdust of the same timber to match the colour, and force it into the hole leaving it slightly proud. Try and use a very fine saw dust. It makes mixing the epoxy much easier and it goes in the hole better. Once it is dry, I use a grinder with sanding pad to flat it and then I use a rotex sander to remove the scratch marks left by the grinder. Now it is ready to be sealed and good luck to any water that thinks it can get in there. The epoxy is the only filler that will last. Wood filler will pop out in a few months’ time. Use a clear epoxy as the saw dust will match the colour of the deck. White or grey epoxy will leave a white or grey mark on the surface.

It takes more effort and takes longer to do it this way, but my crew has it done to a T now. And the net effect is a better built deck that will last longer and will cost less to maintain. So there you have it, the warmth of wood without the hassle and without having to settle for alternative materials.

For a free, no obligation quote or for some advice please feel free to contact us on 082 496 5444 or complete the form below and I will contact you. Please also feel free to leave comments below.

Wooden Sundeck, Toti, Durban

Wooden Sundeck Installer Durban

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We built this wooden sundeck in Toti using CCA Pine, for the first time, as our substructure and decked it using balau deckboards. For a long time I have been using only balau as a substructure. But after some careful investigation I have accepted that a CCA treated pine substructure is as good if not better than a balau one.

The manufacturers of the solution that is used to pressure treat the timber guarantee their product for between 30 to 50 years depending on which manufacturer you use. Provided the company doing the pressure treatment treats it correctly and provided the correct Hazard Level (H level) is used in the correct application, the timber will be guaranteed against rot and insect infestation by the manufacturer of the solution. I will write another more detailed article on CCA pressure treatments, but for the purpose of this article you will need to know what it broadly means.

Wooden Sundeck Installer Durban

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H2 CCA Treated pine is good for roof trusses where it is not exposed to the elements such as rain. H3 treated is good for outdoors such as decks and H4 is good for in the ground or in contact with wet soil. H5 is good for in salty water and is normally a combination of CCA and creosote treatment. H2 is commonly sold off the shelf at most timber yards. H3 and H4 is more specialised so one needs to find a supplier who is regularly treating to H3 or H4. Under no circumstances should H2 be used as a substitute. It will rot within a few years. Simple. Do not use it in decks, keep it for the roof.

Wooden Sundeck Installer Durban

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In order to activate a guarantee against the manufacturer one would need to take photos of the deck going up ensuring that the correct H level is used, an audit process would need to be completed on the company treating the timber and the build would probably need to be registered with the manufacturer and possibly inspections conducted during the build. So although it is possible to activate a guarantee, it is not really practical as the substructure will go up in 2 days and the deck will be done in 5 days. However, if the manufacturer is willing to offer this sort of guarantee, then we can safely assume that the timber we are using will hold up to its promise. In a nutshell, H3 or H4 treated CCA Pine is suitable for a substructure for a deck and may very well outlast a balau substructure. I would not be too keen to use it as deckboards for two reasons. Although it won’t rot or get eaten by ants, it will expand and contract a lot more than balau which will result in checking, cracking, warping, bowing etc. over time. The second reason is that because it is half as dense, one needs to use a 32mm thick deckboard as opposed to a 19mm deckboard in balau. So twice as much timber is used and the cost is actually slightly more in pine per square metre than balau. So why not use balau in the surface? It is much better looking and much more stable (i.e. it remains flat for many more years).

Wooden Sundeck Installer Durban

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The cost saving in using CCA pine vs. balau in the substructure is great and this allows me to keep my prices low whilst still providing a quality product. The CCA Pine will last as long if not longer than the balau substructure if the correct H grade of CCA pine is used.

All areas that have pine exposed are clad with deckboards so that the pine is not visible. Balustrades remain full balau.

For a no obligation quote on wooden decks, balustrades, pergolas and any other outdoor timber construction, please complete the form below and I will get back to you.  Or you can call us on 082 496 5444.