Having trees growing through your deck can help to create an extremely picturesque, novel and dramatic feature. Not only do trees provide natural shade, but they'll also help to add to the 'organic' feel of your deck, and to blur the lines between where your living areas end and your garden actually starts.
Trees are living things though, and as such it's important to realise that it's not always easy to control them. As they grow and move, trees can change positions - not just above ground, but also (and perhaps more critically) under the ground.
If you're planning on allowing a tree to grow through your decking, it's a good idea to account for some of the complications you're likely to encounter further down the line. Some of the risks associated with trees can be easily avoided with a bit of common sense, while others can only be managed as they present themselves. Obviously it's far easier to build a deck around existing trees than it is to create a deck and try to train trees through it in the right way.
Below is a list of some of the issues you may encounter when installing a deck around existing trees:
- Termites - The bane of home owners everywhere, the risk of termite exposure is increased when you have a tree growing in such close proximity to your deck. Ensure you’ve taken the proper precautions in termite treatment such as termite capping on the ends of your framework and the application of termicide where necessary.
- Interference with foundations – Tree roots can grow exceedingly fast and can quickly disrupt your deck support structure. Ensuring that the soil around your foundations is dry will deter any root growth but if it happens, there’s little you can do but repair the damage.
- Increased risk of settling soil – The root growth underneath can cause soil to settle, filling in any air pockets and dropping the level of the soil. This can in turn cause your foundations to sink and lose stability, jeopardising the whole support structure.
- Trunk growth – The most obvious cause of damage is that over time, the trunk of the tree will increase in size, pushing outward from the hole you’ve allowed it to grow through. This can cause nearby boards to buckle and snap, bowing beams and bearers and making your deck unstable. You can prevent this from occurring by allowing a wide enough space for the tree to grow in. Trim any low lying branches, especially from the base of the tree as these can become additional trunks and cause problems later on.
- Tree litter – Trees that drop excessive litter do not make for good deck companions. Shed leaves, dropped branches and over-ripe fruits can turn your deck into a major chore at best and a hazard or a stained mess at worst. You should do some research on the tree if you don’t know what it is or what its habits are, and think carefully about whether your tree will be appropriate for a deck in the long term.
- Tree death – If for some reason the tree growing through your deck should die, you will need to have a contingency plan ready for its removal. A dead tree can pose a threat to your safety and your home if left unchecked.