Why is my patio sinking

These areas should be filled in and the ground should be prepped to ensure it is compacted and level prior to the installation of the paver base.

Shifting and settling can also occur when improper materials are used in the base. In regions like the northeast, soil and natural elements freeze in the winter and thaw in the spring, and so, these materials expand and contract — shifting your pavers. When installing a paver system, the border of the paver area should not be overlooked. The edges of paved areas require special attention, because they are not locked in on all sides.

Without a structured border, any pressure put on the border or surrounding pavers can cause them to shift. To avoid this situation, paver edges should be cemented in to secure the paver structure — a detail which a surprising number of inexperienced and unlicensed contractors neglect to do. A competent contractor will compact the subgrade far enough beyond the footprint of the project to ensure proper stability under the edges of the pavers.

Uneven pavers that shift out of place can be caused by a number of improper installation methods. One very common cause is a base that is not deep enough. A contractor can save a lot on materials by skimping on the base, but it will compromise the structure of the pavers in the long term.

When completing a paver installation, many contractors use a masonry sand between paver joints, which allows weeds to grow through within a year of installation. The right installation contractor will use Sandlock, known as epoxy sand, which locks in pavers, and prohibits weeds from growing through the joints. There are many jobs where pavers are not laid properly, creating a sloppy appearance. The patterns look uneven, or there are large gaps between pavers. This happens most often with inexperienced workers, but rushing through a job can also bring careless results.

No matter what the cause, shifting or improperly laid pavers should be addressed immediately to avoid further damage. Not only does shifting or sinking pavers look bad, but they can also lead to pavers breaking or the base being further compromised, creating a structural break.

Furthermore, broken, sinking or shifting pavers can become a safety hazard. The Damaging Effects of Water Another cause for sinking concrete is water intrusion. How can I prevent my concrete from sinking? Seal all open cracks and joints with a polyurethane or silicone caulk. Large gaps can be filled with a backer rod first and then caulked on top.

Make sure downspouts are discharging at least five feet away from any concrete slab — the farther the better. Tightly pack any open sides of a slab with soil to ensure runoff water is not going below the concrete.

Base should not move when you stomp your feet on it. Also, install all downspouts that are close to any slab such as a walkway should be installed below the concrete and extended into the yard.

How to Fix Settled Concrete. Is Your Concrete in Need of Rescue? Poor soils and trash left from builders absolutely must be removed during the excavation as overstabilization of the patio site is extremely important to its integrity. Oftentimes the inferior soil that is uncovered during excavation is the result of water issues in the house that also bear correcting.

Using the proper amount of fill of modified crushed stone within the excavated site is also part of base preparation. This stone is graded properly, then compacted to form a solid base, a few inches at a time until the finished depth is achieved.

If pavers are sinking, it might be an issue of improper compaction of the base material. If it loosens over time, the pavers can begin to sink. As this happens, pavers can actually begin to crack. This could lead to low areas that will always collect water. But poor drainage can cause other problems as well. Poor drainage can also cause rainwater to collect underneath your patio or come out with such a force that it may begin to destroy the integrity of the foundation of your home. Believe it or not, poor drainage associated with your patio can even progress to affect the inside of your home.

In a poor design, water can become trapped. With nowhere to go, it may flow towards your house and wind up in your basement, leading to tens of thousands of dollars worth of repair work.

All of these problems could be prevented when you start your patio design with a grading and drainage plan. Unfortunately, too often, landscape contractors just install a patio with no real thought as to what drainage problems exist or may be created by the patio installation. In the end, this lack of planning can be a costly mistake. Another common gripe that we hear about paver patios is that weeds can grow in the joints. However, the use of a special sand called polymeric sand in the joints will make a huge difference.

Polymeric sand is a fine sand that is combined with additives usually silica which, when mixed with water, forms a binding agent. Rather than loose sand, which weeds could grow through, this special sand will reduce the amount of weeds that break through.

However, if polymeric sand is not installed correctly, this can pose problems. We see a lot of full patio failures with incorrectly installed polymeric sand. If the specialized sand is installed wrong, it may not stay put, leaving nothing in your joints.

This can lead to a patio full of weeds! In addition, the installation of geotextile fabric, which is a material with a very high tensile strength that is installed underneath of your paver patio, is also a barrier to any weeds breaking through from the soil beneath. Geotextile fabric also strengthens the base of your patio by acting as a bridge over top of the soft spots. While some occasional weeds might pop up from seeds that have blown on top of your patio, the use of these two elements will eliminate most weed growth.

A paver patio that has uneven pavers can create dangerous trip hazards. This is once again most likely due to a problem with the construction of the base.