Deck refurbishment in Kloof

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This was an old deck in Kloof that we refurbished recently. It had balau deck boards on top of a balau structure. Of the 11 joists that made up the structure only 2 were still in a fair condition. The rest had rotted and we needed to replace them. Please see this article on the pros and cons of using balau as a structure. https://blog.thewoodjoint.co.za/2015/06/21/balau-vs-cca-treated-substructure-in-your-wooden-deck-durban-and-cape-town/

The deck was fairly old (20 years plus). 20 years ago most deck builders used balau as a structure. Over time they have come to realise that a chemically treated pine structure will out last a balau structure because it is chemically treated and therefore it’s behaviour is known. The process of pressure treating is safe and arguably does no more damage to the environment than cutting the purpose grown tree down in the first place.

We ended up lifting all these deck boards, numbering them and replacing them in their same position so that we could use the same screw holes. Rather than sliding new joists in below the deck boards.

The deck boards themselves where quite mottled with black algae but the wood itself was still ok so we pressure cleaned the deck and then oiled it with a penetrating oil. In some pics you can see the difference between coats of oil.  The balustrade is all new as the old balustrade had rotted away beyond repair and had been removed by the client.

For a free no obligation quote on your new deck build or deck refurbishment please contact us on 082 496 5444 or use the contact us form below.

Wooden Sun Decks Durban – Westville

Wooden Sun Decks Durban

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Wooden Sun Decks Durban

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This wooden sun deck we built in Westville Durban was designed to try to maximise outdoor space. The house we built it at had very little outdoor space as it was situated on a steep plot. You can see from the pics that before we built the wooden sun deck, the garden had only a small area of about 1m around the pool on the front side of the garden. There was then a steep concrete staircase down the side of the house going to the back garden. The back garden was however not very usable as it was far from any entrance to the house. So the idea here was to build a wooden sun deck that extended from the slasto of the pool area to meet the far side of the house. It was about 48m² in total floor area and was surrounded by a wooden balustrade in a picket design. We left the existing concrete stair case in place and built the wooden sun deck so that one could use this existing stair case. Hence the U Shaped deck.

Wooden Sun Decks Durban

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We also had to split the wooden sun deck into two levels as the area by the pool was a little lower than the area where it met the existing concrete deck. So we had a split level deck with a small step up of about 180mm. 180mm is always a good step height or riser height.

Wooden Sun Decks Durban

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The posts beneath had also been lined up so as to avoid being placed in the middle of the stair case. Even though the outer posts were some distance from the bottom of the stairs, if we had placed them where they would normally have gone (i.e. equal distances from either end) then it would have spoilt the line of sight as one was walking down the stairs. So they were shifted slightly left and right to miss the line of the stairs.

We also had a garden shed beneath the front edge of the deck so we had to build around that which had had a new roof built on it and waterproofed. When building over waterproofed structures one cannot drill through the torch on as it will results in leaks beneath. You need to then build on either side of it or use thicker beams and joists to be able to span them further apart.

Wooden Sun Decks Durban

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Wooden Sun Decks Durban

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In the pics on this article you can also see the horse shoes we used to support the beams on the walls. Instead of dropping posts to ground you can simply attach the beam to the wall by cutting a horse shoe using the same timber as the beams. The bottoms are always cut to 45° for both neatness and to avoid having sharp corners jutting out. This also applies to the ends of main beams.

We treated our cut ends with Permaseal, an approved end sealer used to stop rot or insect damage to cut ends of CCA treated timber. This was necessary in order for us to activate the 50 year guarantee that the supplier provides on the CCA Treated pine substructure. There are a few articles on this blog that go into detail about this and what is required in order to activate your 50 year guarantee.

For a free no obligation quote on wooden sun decks, wooden floors or wooden fences, please contact 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.