The trouble with housing floor joists into bearers

housing floor joistsOne method of connecting your floor joists to your bearers is to check them into the side of the bearer rather than sitting them on top of the bearer. This is commonly done to help reduce the depth of the sub-floor frame and it is especially effective in a couple of situations: when the deck is close to the ground; or when the deck is on the front of a house and you want the bearer to hide the ends of the floor joists.

However this method of checking the joists into the bearer has its own unique problem: over time the floor joists have the potential to work themselves out of the housing, due to the deterioration of the fixings holding them in. To overcome this problem it is recommended to use a metal bracket and screw it to the bearer and then to the joist or you can use what’s referred to as a joist hanger, which is when the joist itself is actually nailed to the bearer via a bracket that the joist sits in. Joist hangers are designed so that you don’t have to check your floor joists in the bearer and offer more stability than just checking a floor joist into a bearer.

In 2008 a deck in Brisbane collapsed killing one person and injuring plenty more. It was found in the coroner’s report that the cause of the deck collapse was because over a period of time the joists had worked their way out of the housing that they were checked into.

Keep in mind when planning your new deck or even renovating an old deck and space is limited, butting floor joists into the bearer is a good option just pay extra attention to how you are going to secure them in place.

For further reading, check out our “Articles”.

Stepped profiles – the key to success

steppedHow a deck will come together is determined even before the first hole is dug.

When you start to measure out your deck, you need to ensure that all your measurements are taken level. I know this may seem obvious, but doing this on a steep site like the one in the photo is not always easy.

Looking at the photo, you may have noticed that the profiles (the temporary timber frames that the string lines are tied to) have different level steps in them. When the profiles have steps in them you are able to transfer measurements between the different steps, while at the same time keeping all the measurements level. Also the stepping process keeps all the profiles at a comfortable working height and makes it much easier to install your footings later on.

For more information on setting out your deck you can purchase our own copy of our “Site preparation and deck set out” guide from the Resource Shop.

What to consider when planning a deck for your spa.

spa deckThere a few considerations when looking at building a deck around a spa. However in this article we are going to look at the longevity of the deck. This is a critical point that needs to be addressed during the planning stage, because timber decks and chlorinated water do not mix very well. This is especially true with spas due to their nature, spas contain warm to hot water.

There are two things that happen. First, warm water, when splashed, soaks into the timber quicker than cold water. This chemically rich water increases the speed of the timber deterioration compared to a deck exposed to the normal weather conditions. To overcome this you need to allow for a stronger, more durable deck coating product. Secondly, as the timber draws in the water, the fixings (nails, screws, etc.) that hold the deck together become exposed to all the chemicals in the water and start to corrode at a much faster rate than normal. To avoid this and slow down the corrosion on the fixings, consider using stainless steel fixings. When you are planning a deck for your spa, make sure you take into consideration the added effects of the water on your deck.

For further reading, check out our other “Articles”.

Raised decking nails, what’s the verdict?

raising nailsThere is nothing worse than walking out onto your deck barefoot and stepping on a raised nail. There are many reasons why nails lift, such as the age of the deck, an incorrect nailing pattern, or even over cleaning of the deck; however the root cause of the problem starts right back at the construction stage of the deck. It can start with something as simple as using an incorrect nailing pattern (bear in mind this is not the only cause, just the most common).

As you can see from the photo the nails have all been nailed in a straight line and this has sealed the fate of the deck. When decking boards are nailed in a straight line the nails act like a series of tiny wedges splitting the floor joist along its length. Over time this splitting of the floor joist is amplified by continuously wetting the deck, either by over cleaning (hosing) or weathering due to age. As the splitting gets deeper the nails are no longer held down by the floor joist and they eventually come free, rising up. When the nails start to lift it is time to make a very serious check all over the deck, including in between the decking boards, to see if the floor joists have started to split.

Best practise to avoid this problem is to stagger the nails rather than nail them in a straight line. This process is outlined in our “Installing Decking Boards” guide.

For further reading, check out our “Articles” section.

When stair maintenance is no longer an option.

stairIt is all too common for people to ignore stair maintenance, especially when considering timber stairs. You may be surprised to know that timber stairs require more care and maintenance than decks do. Stairs have lots of different check outs (grooves for the step treads) in the stringers (stringers are the timber beams that support the step treads) and posts where water can get into the timber. When water gets into the timber it creates the perfect conditions for dry rot, which is the most common form of timber rot.

In the photo you can see the bottom step tread has been replaced, but the timber stringer has not been replaced. It is clear that because of the dry rot there is no solid timber left around the stringer to support the step tread. To overcome this problem, a piece of timber has been screwed to the stringer to support the new step tread – this is a very dangerous practise. If additional timber needs to be added to the stringers to support the new step treads, the structural integrity of the stairs has been compromised and the stringer/s need to be replaced. This photo is a good illustration of a set of stairs where maintenance is no longer an option.

Do you have any maintenance questions about your own deck? Send us an email and we will answer any questions that you have ([email protected]).