Chapter 4: Watering Know-how

You must be wondering after you come cross the title – watering is so simple, what know-how I don’t already know? I’ll let you make the conclusion after you finish reading the article.

Watering bushes and flowers may appear simple, but if you’re doing it wrong, it’ll cause direct damage to building foundation and wood structure. You might have heard that water is the worst enemy of buildings. Once water penetration occurs to a building, it’s very costly to repair. It’s best to prevent it from happening, knowing how to water is one of the key factors.

1. Watering needs to be even around the perimeter of foundation.

Many people like to plant bushes and flowers around the foundation. This will affect foundation stability. In Central Texas, shallow foundation is the common foundation type adopted. Soil mostly consists of silt, clay or the mixture of silt and clay. The characteristic of this type is high soil swell coefficient. When mixed with water, it builds significant lateral pressure against the side of the foundation wall causing unstable foundation structure over time. Therefore, watering must be done evenly to ensure the same soil moisture around the building wall so that the stress is evenly distributed around the building from all directions. This will prevent foundation twist or damage.

2. Water should be sprayed downwards.

You must think this is strange. Are there people who spray water upwards? Indeed, I frequently see people using sprinklers or nozzles towards the eaves, then letting the water drip down to the lawn. This will cause damage to rafters and facial boards or even rot them. As you know, the eave is designed to protect the wood from water penetration. Asphalt shingles on the eave must extend to at least 2-inch from the dripping edge to guide storm water away from the building. When the nozzle with pressure sprays water to the eave, water will penetrate through the seam into the wall, causing damage to the wood structure within the wall, as well as installed insulation materials in the wall.

3. Do not spray water directly to the wall.

There are protective membranes on the surface of the sheathing board. Its function is to prevent water from penetrating into the building reducing material strength, at the meantime, prevent storm water from penetrating into structure and insulation materials. On average, the water pressure is between 40psi and 80psi. This pressure is big enough to penetrate the bricks and membranes and deposit water inside the wall. When water stays inside the wall, due to lack of evaporation path, it’ll eventually damage the sill plates of the load bearing wall, thus degrade its capacity.

4. Avoid water ponding around the foundation wall.

Building drainage requires that landscaping should provide a slope not less than 5% around the foundation wall. The function of building drainage is to guide storm water away from the foundation wall, instead of let it deposit around the foundation. Water ponding is formed by store water dripping from the eave around the foundation over a long period of time. Water ponding not only damages foundation, but also causes rotten soil. That’s why water ponding is emphasized in the inspection report from home inspectors.

I hope you’ve learned something from this article. If interested, you’re welcome to visit www.abtinspections.com to read other articles.

By Michael Zhang

Published in the August edition of Texas Capital News