Train vibrations likely not harmful
QI own a 10-year old, two-storey home on a piled foundation that is approximately 200 metres from railroad tracks. When a heavy train passes, I can feel tremors/vibrations on my upper floor/ If I have a glass of water on my bedroom dresser I can see ripples on the surface caused by these tremors/vibrations. Over the life of this home, is this cause for concern from a structural perspective? What are the long-term effects of these tremors/vibrations? Would the damage be limited to tiny drywall fractures, cracks or nail pops from the small movement?
I am interested on your thoughts on this matter.
Thanks, Jeff Toye
Answer: The effects of long-term vibrations from the trains near your home may be hard to pinpoint or predict, but are much less likely to be serious issues due to the piles under your foundation. Having the foresight to spend the extra money upfront may save you from significant movement, and higher costs, in the future.
Constant vibrations from busy streets with large trucks, buses or trains may have a noticeable effect on some homes. Depending on the proximity to the irritant, these may range from minor to major wall and foundation cracks. The reason these issues may be nearly impossible to predict is that there are a number of other variables that may affect the outcome. Soil conditions, drainage, underground sewers, type of road composition and numerous other factors may determine whether rumbling from nearby vehicles will create serious issues. But the largest factor that may determine whether problems may arise is the structure of the home, itself.
Most newer homes in our area have reinforced concrete foundations, built on a concrete footing buried two to three metres below grade. Because of our wonderful expansive clay soil, settlement of these typical homes is almost guaranteed. Over time, most of these homes will move downward, often in one direction or toward one corner of the foundation. As long as this movement is fairly uniform, and teleposts under the main beams in the floor structure are appropriately adjusted, this settlement may not cause any serious structural issues.
If the settlement is increased or exacerbated by regular, heavy vibrations from a nearby train or busy roadway, it may cause larger problems or lead to foundation damage. If the settlement is minimized by better building practices, the vibrations may have much less effect on the home.
The main way to prevent typical settlement in our homes is to install the foundation on deep concrete piers, or driven piles, rather than footings. Your home likely has concrete piers, often referred to as piles, which may go into the soil for five to eight metres below the foundation. These supports will prevent settlement of the heavy home and foundation by reducing the effects of gravity and also prevent movement related to frost.
The bottom of these piers or piles will be installed way below the “frost line,” or the normal depth that frost will penetrate the soil in the winter. Having structural supports that deep will minimize most vertical movement in a home, but may not fully prevent movement caused by vibrations.
Even with your high quality foundation built on piles, some movement other than up and down may still occur in the house. This can be from environmental factors such as wind and temperature changes, but may also be due to ground movement from traffic vibrations. These forces may be strong enough to cause small hairline cracks or popping screws in your drywall, or some of the other items you have experienced. However, the piers that are preventing vertical movement should eliminate the most serious type of motion. You may still be susceptible to rattling china cabinets, windows, or flooring, but most of the components of a modern home have enough flexibility to prevent serious damage.
The key to determining whether any long-term serious effects will occur is to watch your house closely and nip any of these in the bud, if they start to happen. If hairline cracks, which can develop at drywall seams and corners become larger over time, repairs will be warranted. Re-securing loose fasteners and re-taping and painting walls and ceilings regularly will prevent more serious cosmetic defects. Patching or caulking any exterior components that show wear may also help prevent worse damage from occurring. As with most issues, good maintenance and diligent repairs will stop a molehill from becoming a mountain, regardless of the vibrations.
I would love to be able to tell you that there should be no serious effects on your home from the regular vibrations and soil movement caused by the nearby train tracks, but that is impossible. Predicting that type of failure in a home depends on too many variables, which nobody may be able to fully anticipate.
Regardless, having the good sense to build your home on deep concrete piers, nearby train or not, should make the chances of serious issues much less likely. Ari Marantz is the owner of Trained Eye Home Inspection Ltd. and the past president of the Canadian Association of Home & Property Inspectors — Manitoba (cahpi.mb.ca). Questions can be emailed to the address below. Ari can be reached at 204-291-5358 or check out his website at trainedeye.ca.