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Signs Of Structural Damage
Are you concerned about cracks in your old house's walls or ceiling? The ability to detect structural faults is essential for the maintenance of any home, particularly an older one. Overgrown trees and bushes, damaged drains, a leaky rainwater system, and missing roof tiles might cause structural issues. If left unaddressed, these might require costly repairs and may even result in more frightening structural concerns like sinking and displacement.
Since prevention is crucial, you must keep up with your house's exterior care. But don't worry if you think the harm already happened — with the help of an expert, structural problems, including cracks, always seem to have a solution. Continue reading this article to determine whether it is normal for old houses to have cracks.
Is It Common For Old Houses To Have Cracks?
Structural damages affect your house's core integrity, with the foundation, walls, roof, and load-bearing walls all falling under this category. Wall cracks are pretty common in both old and new houses and are often caused by standard house "settling," which can be remedied quickly and inexpensively by re-taping the joints—the seams where the drywall panels meet.
When there is structural damage, your old house may no longer be able to support itself and may be on the verge of either collapsing or failing. Fortunately, several warning signs will alert you before any severe damage happens. So, let's take a thorough look at a few of those red flags.
What Causes Cracks In Old Houses?
The first step in determining the severity of wall cracks in your old house is identifying the indicators of structural damage. Some of the following factors might cause your old home to have wall and ceiling separation due to extensive cracks:
Subsidence and settling
When a house gets built, it requires some soil excavation. Some types of dwellings need more soil disruption during construction than others. Over time, this soil becomes compacted and settles, causing cracks to appear. Natural settling frequently results in tiny vertical fissures rather than large jagged cracks. Minor settling is a natural occurrence that happens over time.
However, significant downward motion in the soil beneath a wall indicates structural problems. When the soil gets washed away, compacts too much, or collapses, it results in severe subsidence. A spectacular example of this is sinkholes.
When wet, reactive soil expands substantially, and when dry, it compresses significantly, resulting in wall cracks. One example of reactive soil is clay. Sand and gravel are also examples of non-reactive soils. Soil testing will help you determine whether your soil is reactive and could be causing a crack in the wall.
Seasonal and climate changes
Drought, floods, climate, and seasonal changes can induce severe contraction and expansion of the soil. They can also create significant changes in the water table well below a property, resulting in the home's structural problems, such as wall cracks.
Nearby excavation and construction work
You might experience cracks in walls if you reside in a new housing development or are near a building site or a quarry. Heavy machinery, vibration, severe mechanical compaction of the soil, or blasting (excavation using explosives) can all cause house cracks in your walls, especially if it is old.
If your wall cracks appear after a building has been constructed in your neighbourhood, you might get a crack examination and legal guidance. Earth tremors and earthquakes, however uncommon in Australia, can also cause wall fractures to form.
Poorly constructed extension work
Internal wall cracking might occur if extension work is done in your house without retaining the walls. Wall cracks might arise when too much weight is put on a load-bearing wall. In addition, faulty building materials and under-engineered footing design might also cause wall cracks.
Cracks in the wall might also occur due to clogged box gutters, flood damage, garden sprinklers, and blocked or leaky pipes. All of these can saturate or even wash away soil.
Planting trees close to your house
Invasive root formations are common in trees, leading to cracks in your house. Therefore, you must ensure that you only have modest plants and shrubs growing close to your walls. Trees can cause the old wall to crack by removing water from the soil and altering the soil's moisture content.
As it can destabilise the soil in the space formerly occupied by the root system, removing a large tree from a location near your walls might also cause cracking. It can also cause changes in the soil's moisture content or settle over time.
Degradation of building materials
Nothing lasts forever, and construction materials are no exception. Building materials can get harmed by several things, including gravity, weathering, rotting, or inadequate maintenance. When your building materials begin to deteriorate, your house's structural integrity gets jeopardised, and it may yield to gravity.
This could, in turn, lead to the formation of cracks. Another probable cause of your old wall cracking in your house is the degradation of its concrete slab. The steel inside reinforcing the concrete begins to rust and disintegrates due to moisture and salt exposure resulting in concrete cancer. Therefore, an old house is prone to wall cracks.
When To Worry About Cracks In Your House
No cracks are alike! They come in a variety of sizes, shapes, and directions. Larger cracks (those measuring more than around 15mm in width) are usually a source of concern. Therefore, you should have a structural engineer check these. Subsidence cracks are more likely to form quickly.
They are commonly found near or around doors and windows and are diagonal and broader at the top than the bottom. Below is a list of cracks to be concerned about:
Hairline cracks with less than a width of around 1mm or minor cracks of around one to five millimetres are not a reason for worry. These are cracks in the plaster rather than a break in the wall. You can typically fix them by patching and painting over them.
It is dangerous when a crack is between five and fifteen centimetres wide. When an old wall has a crack that is around 25 mm or wider, it might indicate structural damage. A large fracture like this might necessitate extensive work, such as underpinning, to secure the stability of the structure.
A significant cause of structural movement is jagged cracks that run diagonally or seem like a series of steps climbing up your old wall. They are also a little more dangerous than cracks that just run up and down an old wall. You should assess the length and depth of the fracture and seek the advice of a structural expert who can determine the severity of the problem.
Tiny fractures like this are common in old plastered walls. They can occur when the plaster swells in the presence of moisture and then contracts as it dries. Instead of immediately filling and repainting the cracks, you should wait for some time before filling and repainting them. However, if the vertical fracture exceeds 0.5cm, it might indicate a more serious issue.
Horizontal cracks in cement blocks and brick foundations are more prevalent and indicate a significant problem. They typically run from wall to wall and occur when the foundation walls get strained by water pressure and uneven soil. These cracks are more likely to appear due to periods of heavy rain, especially if your home has inadequate drainage.
As such, structural damage might occur as a result of this strain. To prevent horizontal cracks, you should ensure that your downspouts are far enough from the foundation of your property and ideally connected to stormwater. Depending on your house and soil, a soil specialist can advise you on the ideal distance. Downspouts should discharge at least four feet away from your home.
Wall cracks can occur between mortar joints and individual blocks due to soil pressure or differential settlement (when a home's support foundation settles unevenly). Stair-step cracks resemble diagonal cracks, but they create a stair-step pattern on your old wall.
Cracks above window and door frames
Cracks are most likely to occur in the weakest portions of an old wall, such as around a window frame. It is mainly since windows and doors weaken walls significantly, allowing fractures to emerge.
Cracks through which you can see daylight
Cracks in the walls and ceiling that allow light into your house can be a reason for severe structural damage. Such cracks indicate that the entire wall has changed, not just one side. A fracture may appear on the outside of an old wall, but it might not be visible on the inside, and vice versa. One enormous fracture that looks to run the width of your wall, on the other hand, might be a symptom of subsidence.
The Cost Of Fixing Cracks
If the cracks in your old house are severe, leading to structural damage, they might be costly to repair. The expense of ignoring wall cracks, on the other hand, might be far much higher; you could end up with a property that is utterly uninhabitable or even condemned. Your insurance policy may or may not cover the cost of repairing wall cracks and addressing the underlying causes.
On top of your existing mortgage obligations, you might find yourself stuck with the price of relocating and renting an alternate house. If you want to save money in the long run, it is better to correct the wall cracks and all their underlying causes as soon as feasible. After all, there's no arguing against the fact that prevention always trumps any form of cure.
Home insurance can cover cracks that are subsidence-related. But you will have to pay an extra fee, which is often more than the excess for claims on the remainder of your policy. Keep in mind that once you file a claim, your insurance company might want to check on the crack before choosing how to best address it.
On the other hand, cracks due to natural settlement, thermal movement, and lintel failure will fall under a maintenance issue. And you are likely uninsured against cracks caused by the aforementioned because building insurance does not cover wear and tear or regular deterioration.
How To Repair Wall Cracks
If the cracks you are trying to deal with are broad and deep, you might have to contact a reliable structural engineer. Structural engineers can figure out what's causing the cracks and how to remedy them.
On the other hand, you can readily correct small hairline cracks in your old plastered wall, putting your practical DIY skills to good use and saving money. To repair hairline cracks, follow the steps below:
Step One: Softly scour around the fissure
To begin the repair, softly scour around the fissure with a putty knife or scraper. Doing this increases the surface area where you will add the jointing compound and improves its adhesion to the surface.
Step Two: Fill cracks with a joining compound
Then, fill the cracks with the jointing compound at the surface using a putty knife. Be sure to apply it in thin layers rather than one single application. This will allow you to get a flawless, smooth finish.
Step Three: Add a fibreglass mesh to the wet compound
While the compound is still wet, add a fibreglass mesh to the crack and surrounding area to cover it. You can make use of a pair of scissors to trim the mesh to size, but do not worry about being too accurate. The mesh will keep the crack from growing big, making it a necessary precaution.
Step Four: Allow the compound and mesh to dry
Now, give the compound some time to dry.
Step Five: Add three more coats of compound
Apply three more coats of jointing compound over the mesh after it's dry. You must not rush through this task as you need to allow each layer to dry completely and sand the area before applying the next. Ensure that you increase the surface area of the compound as you add each layer because this will help achieve a smooth finish.
Step Six: Cover the area with sand
Cover the area with some sand once the final coat is dry (wait around 24 hours to make sure this is the case).
Step Seven: Brush away any dust and paint the drywall
Lastly, brush away any extra dust and paint over the drywall compound to match the rest of the wall.
Tip: This procedure works best in repairing typical cracks that your homeowner's insurance might not cover.
Hire Experts To Fix Cracks In Your Old House
If you discover some cracks in your old house but are unsure of whether to be concerned, it is better to be safe rather than have regrets. Therefore, you could hire an experienced structural engineer or building inspection expert to evaluate the cause of wall cracks.
Such experts can help you with strategies and estimate how much the necessary repairs will cost. It is essential to safeguard your family's safety and your financial investment by dealing with any cracks you come across in your new or old house.