Many times I have done a site visit to do a measure up for pricing a job. What I notice fairly often is that a lot of concrete surrounds already done around houses are done too high. What are high surrounds? Why are high surrounds a problem? How can you check if your surrounds are too high? What can you do if they are?
What are high surrounds?
You may not even know what ‘surrounds’ are. In construction, everything that gets built outside your house can be called ‘surrounds’. When it comes to concreting, it is usually used to describe the patios, pathways, hot water and rain water tanks slabs, lawn locker slab etc. They all surround your house.
What I call ‘high surrounds’ are specifically surrounds that butt up against the house and have been placed higher than they should be.
Why are high surrounds a problem?
The answer to this question is one word: termites.
High surrounds will be placed too close to your house’s weep holes. Weep holes can be found around the perimeter of your house, in the exterior wall, hopefully at least about 200mm above the ground. They are small holes intentionally left at the base of the exterior wall to allow moisture to weep out of the masonry wall.
So now we have an entry point into your house’s walls which is design to weep moisture from it. This is where termites are going to naturally be attracted (because of the moisture).
The bad part for the termites is that they don’t like sunlight at all. So they need to create little mud tunnels around their travel path if they want to travel across an area that gets sunlight on it. If your weep holes have enough distance from the ground to the weep hole, the termites will be forces to make a mud track which you can see , destroy and if needed take further protective measures.
However, if your surrounds are too high, they will reduce the distance to the weep holes for termites, allowing them to travel into your house faster and possibly without you knowing!
How can you check if your surrounds are too high?
This is pretty easy. You only need a tape measure or a ruler and to walk around the outside of your house. If you walk around the outside of your house, take note of where the weep holes are in the wall. They are easy to see on rendered homes, sometimes they are harder to see on brick homes as they blend in a bit. Take a tape measure or ruler and measure how far it is from the bottom of the weep holes to the ground level. You need to have a minimum of 70mm or 7cm between the two.
Anywhere that either the ground (grass, dirt, stones, gravel or gardens), paveers or any concrete surrounds are closer than 70mm to the base of the weep holes you may potentially be inviting termites into your home.
What can you do if your surrounds are too high?
If the surround is dirt/earth, grass or a garden bed you can simply dig to lower the area and remove what you dig away. If the surrounds are pavers you may also be able to lift them up and remove the bedding below until you have enough clearance from your weep holes. If the surrounds are concrete you need to know if a physical termite barrier was installed below the slab before it was laid, or if there is a termite reticulation system below the slab that poison can be pumped into, if there is you don’t have a problem.
If you are unsure what is under the slab (you may not have owned the home when the slab was laid) you do have a couple of options that a termite or pest control company can do for you such as traps or drilling through the slab to insert poison.
Plan Ahead and Invest
If you plan to have surrounds laid around your home, make sure you consider the heights of your house’s weep holes. A good concreter will know all of what you’ve learnt here, and will be able to provide a solution that fits your needs. A little bit of planning and a little bit of investment before you lay your surrounds could save you a big problem in the future.