How Long Does Underpinning Take?

Underpinning is a critical process in many construction and renovation projects, particularly in older homes or buildings where the foundation has settled or weakened over time. One of the most common reasons for underpinning is basement lowering, a method used to increase the height of a basement by lowering the foundation. This process not only adds valuable living space to a home but can also significantly boost its property value.

While the benefits of basement lowering are clear, homeowners often wonder how long such a project will take. The timeline for underpinning varies widely depending on several factors, including the methods used, soil conditions, and the complexity of the structure. In this article, we’ll explore the different methods of underpinning, typical timelines, and the various factors that affect how long it takes to complete an underpinning project.

Typical Timeline for Underpinning

The typical timeline for underpinning varies depending on the method used, the complexity of the project, and the factors mentioned above. However, in general, you can expect the following timeframes for a basement lowering project:

  • Small Residential Projects: 3 to 6 weeks
  • Larger Residential or Commercial Projects: 8 to 12 weeks or more

Keep in mind that these are rough estimates, and the actual timeline may vary based on site-specific conditions.

What is Underpinning?

Underpinning is the process of strengthening and stabilizing the foundation of an existing building. This can be done for several reasons, including:

  • To repair a damaged or weakened foundation.
  • To accommodate basement lowering or foundation deepening.
  • To provide additional support for a building that has been altered or extended.

Underpinning is often necessary when a building has experienced subsidence, which is the downward movement of the ground that causes the foundation to settle unevenly. Subsidence can lead to cracks in walls, uneven floors, and structural instability. Underpinning helps to prevent further movement and stabilizes the foundation to ensure the safety and longevity of the building.

Methods of Underpinning

There are several methods of underpinning, each suited to different types of projects and soil conditions. Below, we’ll explore the most common techniques used in underpinning, especially in the context of basement lowering:

1. Mass Concrete Underpinning

This is the oldest and most traditional method of underpinning. It involves excavating small sections beneath the existing foundation and replacing the excavated soil with concrete. Over time, the new concrete foundation is extended deeper into the ground, effectively lowering the basement floor.

  • When to Use: This method is best suited for shallow foundations or when the soil beneath the foundation is relatively stable.
  • Pros: Simple to execute and cost-effective for smaller projects.
  • Cons: Labor-intensive and time-consuming, as each section must be excavated and poured one at a time.

2. Beam and Base Underpinning

This method involves the construction of a reinforced concrete beam that transfers the load of the structure to concrete bases located at a lower level. In basement lowering, this method allows for a more uniform distribution of the building’s load, especially for larger or more complex structures.

  • When to Use: Ideal for larger buildings or projects where load distribution needs to be even.
  • Pros: Provides greater stability for larger projects.
  • Cons: Requires more engineering and planning, which can increase costs and time.

3. Mini-Piled Underpinning

In cases where soil conditions are poor or access to the foundation is limited, mini-piled underpinning is an effective solution. Mini-piles are driven deep into the ground, bypassing unstable soil layers until they reach a stable stratum. They are then connected to the building’s foundation using concrete caps.

  • When to Use: Suitable for areas with poor soil conditions or where access is restricted.
  • Pros: Effective for deep foundations and areas with difficult soil conditions.
  • Cons: More expensive due to the specialized equipment and expertise required.

4. Pile and Beam Underpinning

This method is a combination of mini-piling and beam underpinning, where piles are driven into the ground, and a beam is constructed to bridge the piles. It is often used when the soil conditions vary across the site, making it necessary to provide additional support in certain areas.

  • When to Use: Ideal for complex projects with varied soil conditions.
  • Pros: Provides customized solutions for difficult projects.
  • Cons: Higher cost and requires more detailed planning.

Factors Affecting the Timeline of an Underpinning Project

Several factors can impact the timeline of an underpinning or basement lowering project. Understanding these factors can help homeowners plan more effectively and set realistic expectations for project completion.

1. Soil Conditions

The type of soil beneath your home plays a crucial role in determining how long an underpinning project will take. Some soil types, such as clay or silt, are more challenging to work with, while more stable soils like sand or gravel may allow for quicker excavation and underpinning. If the soil is too loose or unstable, the contractor may need to use specialized methods like mini-piles, which can extend the project timeline.

2. Building Size and Structure

The size and complexity of your home or building also affect how long it will take to complete the underpinning. Larger buildings with more complicated foundations may require more time to excavate and reinforce. Additionally, older homes may have weaker foundations that need to be carefully shored up during the process, adding to the overall timeline.

3. Weather Conditions

Weather can have a significant impact on construction timelines. Heavy rain, snow, or extreme temperatures can slow down or halt the underpinning process, particularly if excavation work is involved. Cold weather can also delay concrete curing, which can add days or even weeks to the project.

4. Permits and Regulations

Depending on where you live, obtaining the necessary permits for underpinning can be a time-consuming process. Some municipalities require extensive paperwork and inspections before construction can begin, which can add several weeks to the overall timeline. Be sure to factor in the time it takes to get all the necessary approvals when planning your project.

5. Contractor Availability

The availability of skilled contractors is another factor that can impact how long an underpinning project takes. If you’re working with a highly sought-after contractor, you may have to wait several weeks or even months before they can start your project. Additionally, if specialized equipment is required for your particular underpinning method, you may face delays due to equipment availability.

6. Unforeseen Issues

Unexpected problems such as underground utilities, contaminated soil, or hidden structural damage can also add time to the project. It’s not uncommon for contractors to encounter issues once excavation begins, which can require additional planning and resources to address.

Post-Project Considerations

After your basement lowering project is complete, it’s essential to take steps to ensure the long-term stability and safety of your new space. Proper maintenance and monitoring can help prevent future issues and prolong the life of your newly strengthened foundation.

1. Foundation Inspections

Schedule regular inspections of your foundation to ensure there are no signs of shifting or settling. Early detection of any issues can help prevent more extensive (and expensive) repairs down the road.

2. Waterproofing

Ensure that your basement is properly waterproofed to prevent water infiltration, which could weaken the foundation over time. This is especially important in areas with high water tables or frequent rainfall.

3. Ventilation and Moisture Control

Proper ventilation is key to preventing mold and moisture build-up in your newly lowered basement. Consider installing a dehumidifier or a ventilation system to keep the air dry and healthy.

4. Drainage Systems

Maintain your home’s drainage systems, such as gutters and downspouts, to ensure water is directed away from the foundation. Poor drainage can lead to water pooling around your foundation, increasing the risk of damage over time.

Final Thoughts: Planning Your Basement Lowering Project

Underpinning and basement lowering are transformative processes that can enhance both the functionality and value of your home. While the timeline for such projects can vary based on factors like soil conditions, the complexity of the structure, and the underpinning method used, careful planning and a knowledgeable contractor can help keep the project on track. Understanding these variables will allow you to make informed decisions and set realistic expectations for your basement lowering project, ensuring a smooth and successful outcome.

Foundation cracks in Toronto are common due to the age of the housing in the GTA, as well as the weather (rain-snow-freezing-thawing).  Foundation cracks develop over time for a variety of reasons and leads to basement water leaks as water makes its way into through the foundation.

Foundation cracks may not seem appear too serious at first, but there’s always a chance they could cause some damage further down the road. This is why it’s a good idea to have them inspected by a professional. Horizontal and/or vertical cracks in a foundation usually won’t threaten the building’s structural integrity as cracking from earth settlement below the foundation and drying of drywall tape or concrete typically won’t cause a problem.

Foundations Move and Shift Over Time

Buildings continually move when the framing shifts and the earth contracts and expands due to heat and humidity fluctuation. Most homeowners won’t even notice the movements since they’re so small, but older homes were often constructed with a reliance on friction and gravity to hold the components of the building in place. The structure can weaken over time and then settle and spread. If the problem isn’t looked after, the building could collapse under its own weight. However the components are all tied together in newer buildings to form a single unit to stop this from happening.

Some structural defects are often hidden inside of walls and under the ground while others are more obvious. Since damage to the structure can be caused by moisture you should inspect the foundation if water from any source is running to it. If the foundation has been penetrated by water it’s generally due to a drainage problem. Salt will wash through a foundation and the rebar and wire mesh will rust away. When this happens the concrete will crumble as the foundation fails.

Leaks in plumbing, doors, windows and/or siding can cause rotting in wood and this can damage a structure’s integrity as the wood can turn to dust. If you find any rot in the trim around doorframes or windows or in there could be some hidden damage. If wood is untreated it may become moist due to contact with earth or concrete and start rotting on the inside. This is often a problem supports and columns for porches and decks.

If termites are present the wood can quickly turn to powder and when a wooden structure is touching the ground there’s usually some hidden damage. The easiest place to visually see any structural damage in a building is the top floor as shifting caused by rot or the movement of the foundation is more pronounced on the top level. Door and window frames will move more on a higher level than a lower one. If the higher levels have uneven floors it’s usually because the structure below isn’t properly supported.

Inspecting For Foundation Cracks

One way to check for structural problems is to inspect the corners of door and window frames with a carpenter’s square. If you find they’re not square it could be because there’s been structural movement below. Be aware that improper installation of the window or door could result in the corners not being square. If just one window or door frame isn’t square this is the likely cause since structural movement will generally affect more than just one frame.

You can check for uneven floors by placing a marble on the floor and see if it rolls. A slightly uneven floor isn’t necessarily bad news since some foundations are designed to ride the movement of the soil the same way a ship rides the waves. Buildings with these types of foundations may not always be perfectly even at all times. But if the floor is sloping in more than one direction then you should have it checked out.

When there’s structural movement it can result in cracking and the cracks can more or less tell the direction and location of the force which caused them. A crack shaped like a V could indicate upward-moving pressure. Upward-moving forces can happen when the soil expands and when the level of moisture is increased in the earth beneath foundations, patios, driveways and sidewalks. Float walls are usually built into basements of structures erected in expansive soil and the float wall is designed to expand and contract with the movement of the soil. If the walls are rigid the force of the expanding soil can push on them and damage the floors above.

Downward Pressure

A downward force will create a vertical crack which is wider at the bottom than the top and the force often originates from subsidence of the soil located below the building’s foundation. A structure can also be damaged by outward or inward force. Horizontal cracks usually aren’t serious, but if the surface below or above the crack has been forced outward or inward there could be problems. Inward or outward pressure can be the result of improper backfill, pressure of moving water and earth, or vehicle traffic that is too close to the foundation.

If you can determine the direction and lace of the force which has caused the cracks then it’ll be easier to find the source. If the damage is hidden though, it can be very hard to determine and costly to repair as floors, ceilings and walls may need to be opened to reveal the damage. It’s also possible you won’t realize there’s any damage until the structure eventually fails.

Foundation Tips When Buying a Home

When buying a home, it’s recommended that you inspect the patios, driveways and sidewalks to see if they’re sunken, heaved, cracked or twisted. If they are then the property may have expansive soils. If the foundation and other structures have been built for the conditions and water is routed away from concrete pads and the foundation you should find little indication of any concrete damage. Remember that most homes erected on expansive soils generally show some defects due to the constant expansion and contraction of the earth. It’s a good idea to have your home inspected if you’re unsure of any damage or contract a structural engineer for a professional opinion.

Have a questions about a crack in your foundation?  Nusite Waterproofing serves Toronto and the surrounding GTA.  We offer a free in-home inspection and estimate and can advise on how to repair your foundation crack.  Contact us here today to schedule an appointment.

Do you have cracks in your foundation floor?

Cracks are a common feature in most homes, especially here in many parts of the US, where you have older homes with foundations that are decades old.   There are many things that can cause cracks to appear, from poor initial workmanship, to a shifting of the foundation itself.  Cracks can be harmless or can mean serious trouble, what you need to find out is what’s causing the cracks in the first place.  Once cracks form in the foundation, water is usually soon to follow.  Many places in the country sit on top of high water tables, which can cause waterproofing issues in your basement.

The good news is that foundation floors are seldom structural. That’s because they are concrete poured in between foundation work. There are two reasons why cracks may develop in this. These are:

  • The earth beneath the foundation was inadequately compacted before the concrete pour, and gave a little under the extra weight, causing uneven support for the foundation.
  • The concrete cracked because that is what large concrete areas generally do as they dry out. Some builders keep concrete flooring moist for longer periods of time to avoid this.

Hence your cracked concrete basement floor is not something you need to fret about for safety’s sake but can also cause water issues. Or is it perhaps? Read on and discover things you may not know.

Gas Intrusion

Undetectable methane and radon gas accumulates in pockets underground which are seldom tested during surveys.  Sometimes a builder may disturb one and cause the gases to gradually escape. While the foundation work is supposed to keep them harmless a cracked basement floor manifestly cannot. Methane gas is violently explosive. Radon gas is the most potent cause of lung cancer after cigarettes.

Insect Infestation

Concrete floor cracks are perfect breeding places for ant and termites, from where they can fan out everywhere in your home. Tackling them upstairs is hardly the right place to start when they’re reproducing themselves constantly in the floor below. In extreme cases wide cracks can even harbor snakes. Thankfully, this is uncommon.

Damp and Mold

There’s always moisture underground. That’s where rainwater naturally ends up, and after that can go almost anywhere. The force of gravity pressing down on the earth above makes ground water surprisingly intrusive. If you ignore non-structural floor cracks, don’t be surprised to find water bubbling up through them after heavy rain.  If your home sits on a high water table, cracks can be an open invitation for a wet basement.

This problem is especially serious in basements underground. That’s because we seldom go down there to inspect. Damp conditions below the earth’s surface are perfect conditions for moss and mold to grow. Especially if the room’s kept tightly closed, and there’s no exchange of fresh air.

Fixing Foundation Floor Cracks

Like most things in life, there’s a right way and a wrong way to seal floor foundation cracks. The wrong way is to conceal the problem with surface filler. The better way is to pour in a polymer compound that forms a bond with both concrete sections. Best of all for wider cracks is to use an epoxy filler to recreate the original monolithic pour. However the stuff is expensive and you may need a concrete flooring specialist with experience and the right injection tools.

 

Coming up with an average cost for foundation repair work can be quite difficult since there are so many factors that need to be considered. It all depends on the extent of work that needs to be done, as well as the type of foundation, the soil, the repair method used, your location, accessibility and the time and labor involved. For instance, a minor job could cost as little as a few hundred dollars while major repair work may run as high as tens of thousands.

Here in The Bay Area, we repair all types of foundations.  Some are easy fixes, while others can be quite the engineering challenge.

Costs For Foundation Repairs

Some other foundation repair costs that need to be considered include hiring a structural engineer, obtaining soil reports and building permits, seismic work, slabjacking and pier costs. There could also be a few hidden obstacles in the way such as deep footings, old repairs, and tree roots etc. If you require foundation work on your property due to flooding or faulty plumbing, be sure to contact your insurance company to see what is and what isn’t covered under your policy.

When purchasing a new home, it’s recommended that you hire a home inspector to see if there are any problems that need to be dealt with. If there are, you can simply walk away from the deal. However, if you already own the home and a problem arises you’ll need to repair it. When you come across a foundation issue it’s certainly better to rectify it sooner rather than later so it doesn’t become worse, unsafe and lead to irreparable damage.

In some cases, major repairs which need the use of hydraulic piers may cost an average of $10,000 or more, while minor cracks that only require crack filler may be fixed for an average of $500. However, the average repair often comes somewhere between the two prices. Two of the most common methods for foundation problems involve piering or slabjacking. When piering is used it means supports are placed underground to support and lift the concrete. This means the contractor needs to dig several feet down to make sure the pier is solidified. It’s then placed beneath the foundation and operated with hydraulics as it lifts foundation to where it should be and stabilizes it. Several piers are used and located at different locations under the home’s foundation.

When it comes to slabjacking, a mixture of grout is placed beneath the concrete foundation and it floats the foundation to where it should be. In general, the piering method is usually the most costly since excavation is required and the hydraulic piers have to be installed. For more detailed information on foundation repairs and a free, thorough no-obligation estimate, contact a local waterproofing contractor

Get Estimates On Foundation Repairs

A good contractor help to estimate the cost of foundation repairs by consulting with you and providing you with a free inspection and estimate of work. Once we’ve discovered the cause of the problem we can decide on the best method to repair it and evaluate with you the costs involved with the project. Just remember, that you shouldn’t consider any estimate if the company you contact doesn’t visit your home and inspect the property first. It’s also recommended that you contact more than one contractor for an estimate.

In addition, don’t be afraid to ask any questions you may have concerning the work. You may be interested in the method of repair used, if there are any financial payment options, how long the job will take, is the work guaranteed and if there are any hidden repair costs etc.  Since foundation settlement may result in major structural damage, we make sure our estimates are as accurate as can be, so you can decide whether or not you want to start the repair work right away.

 

Cracks in foundation Toronto home

If you have a leaky basement you could solve the problem yourself if you’re handy or you may be better off seeking professional help. It will depend on what exactly the problem is and how complex the work is involved in repairing it. Of course, if you’re not able to pinpoint the source of the leaking water that’s probably an indicator that you should call a waterproofing contractor to find the root of the trouble. If you have small cracks in the foundation you may be able to plug them epoxy. But while this may help stop the water from entering the home it doesn’t solve the underlying problem. We have been repairing foundation cracks and water leaks in Toronto for over 30 years, While some things are minor and can be left alone or repaired yourself, other things can be an indicator of major problems and should be investigated.  Below are some situations in which you should probably call a waterproofing contractor.

Chronic Water Around Your Foundation

Water can accumulate around your home by pooling in the soil around its foundation. The soil then expands and can place pressure on foundation footings and walls. In turn, this can result in cracks. You should always make sure the downspouts and gutters are free of debris and in working properly. The soil around the home’s foundation should be properly graded by sloping at a minimum of six inches for each 10 horizontal feet. Many foundations have a drain system installed around the perimeter which is designed to move water below the surface away from the home’s foundation. This drainage system can sometimes get clogged and if t does you’ll need a professional contractor to unblock it.

Cracks in The Foundation

If the home’s foundation is cracked or has tipped, it will need to be reinforced to prevent it from deteriorating even more. The walls may be able to be repaired from the interior with steel braces, wood, wall anchors or carbon-fibre mesh. This will help prevent the foundation from any further shifting. As an alternative, the repair could involve the spreading of epoxy and then and using carbon-fibre mesh to make sure the wall is locked in place. If wall anchors are used they’re comparable to large bolts. Your yard will be excavated and metal plates are installed inside the foundation walls every six to eight feet. These plates use steel rods to connect them and they will help to help straighten and stabilize the wall.

Water Entering The Foundation

If a part of the home’s foundation has been washed out you may want to seek help. Water can get inside a foundation’s perimeter via a drainage issue, a clogged gutter or a broken water pipe. The affected area may be shored up with concrete or by leveling the area. However, you may need to take out a part of the foundation and then re-pour and tie this new section to the old with epoxy and rebar. Since there are numerous reasons your basement may be leaking and need waterproofing you can save a lot of time, energy, and money by calling a professional foundation contractor to find where the problem lies and what the most effective and least-expensive solution will be.

If you’ve called in a professional foundation company it’s a good idea to ask for a written report which lists the specific problem your facing as well as the options which can be used to repair it. You should also ask the contractor for the pros and cons associated with each of the repair methods. For more information on leaking basements and waterproofing solutions in the Greater Toronto Area please feel free to contact us at Nusite Waterproofing for prompt assistance.

 

Chances are that you have heard the word Radon before. Most people have. They have heard the word and know it’s supposed to be bad, but as far as what it is and where it comes from, most people don’t know. It’s hard to protect yourself and your family from something you know little or nothing about; so here are the basics to help you stay safe.

The city of Toronto lists it on their website as a major indoor environmental pollutant.

 

What is Radon?

Radon can be found all over. It is a colorless, scentless and radioactive gas that forms as uranium breaks down in the earth’s ground. This means that radon is everywhere in the world.

The radon gas works its way up through the soil and then into the air. The radon in the air then makes its way into your home from cracks and gaps in your home’s foundation. There have also been cases of radon entering a home through well water. This means as you run your kitchen sink or take a shower the steam is releasing radon gas into the air.

Once the gas enters your home it becomes trapped. According to the US Environmental Protection Agency (EPA), 1 out of 15 homes has radon levels that are elevated. You might be wondering, “If radon is everywhere what’s the problem?”

What are the dangers of Radon?

Most people understand the risk of a fire in their home or that smoking causes cancer, so they take action and buy a smoke detector or stop smoking, but what about radon?

Radon is believed to be the second leading cause of lung cancer behind smoking. As a radioactive gas, radon is a carcinogen. The EPA estimates that 21,000 lung cancer deaths each year are caused from radon exposure. If you happen to be a smoker and you have high levels of radon in your home, you actually double your risk of getting lung cancer.

Just as you install carbon monoxide detectors in your home to alert you from possible carbon monoxide poisoning, it’s important that you take action to reduce your exposure to high levels of radon. So, how do you protect yourself from something that you cannot see, hear or smell?

 

How to protect yourself from radon

You can protect yourself and your family by having the radon levels in your home tested. There are several testing options:

  • “Do It Yourself” test – You can purchase DIY kits online or at many retailers to self-test the radon levels in your home. There are short term kits, which test the levels over the period of a few to 90 days and there are long term kits that test the levels over a period of 90 days or more. Radon levels can vary with the seasons and long-term test kits can be more reliable.

 

  • Have a professional radon contractor test your home for you. You can pay a qualified technician to complete the testing in your home. They can also make recommendations and help you reduce the radon levels in your home if they find that your house has elevated levels.

 

Since radon is created naturally in the environment you might be wondering if there are solutions that can lower the exposure level in your home; you’re in luck. According to the EPA website, “Some radon reduction systems can reduce radon levels in your home by up to 99%. Even very high levels can be reduced to acceptable levels.

 

You can make improvements to your existing home by sealing cracks in the foundation to help reduce the radon gas from entering your home in the first place. Some building materials in homes also introduce radon gas into your home, but current building materials are more environmentally friendly for all.

 

What do I do now?

If you are in the process of buying or selling a home, call in a professional to have your home (or future home) tested. Many buyers are looking for this information when buying a home and elevated radon levels could break the sale of your home.

One of the most common foundation problems for older homes in Toronto is the crumbling of mortar joints between the stones. The repairing process of a stone foundation will depend on several factors since not all repair jobs are the same. However, repairing the bad joints isn’t generally considered to be a big task as long as it’s completed before the basement walls begin to move and the stones fall. Repairing the joints isn’t as expensive as completely rebuilding a wall section.

Crumbling Stone Foundation in Toronto

Using Your Basement as a Living Area

Some stone basements are used as living areas by homeowners, but more commonly, the basement will be used as a storage area for the furnace and water heater etc. And in some cases, the basement isn’t used at all as it’s basically just a foundation and is comparable to a high crawl space. The way the basement is utilized by a homeowner will usually dictate how the repairs will be carried out. If the basement is being used as a living area, then the homeowner will want the finished product to be attractive.  If the height of the basement is inadequate for living purposes, basement lowering is also an option.

Appearance is important in this scenario, but it takes more time and work to make sure the basement looks nice after repairing it due to crumbling mortar joints. If the basement is being used as a storage area and to house utilities, then most homeowners aren’t too concerned how attractive the finished wall is as long as it’s been properly repaired. In this case, their main concern is the structural integrity and function of the finished job. The same is true of homeowners who simply use the basement as a foundation.

Repairing a Crumbling Stone Foundation

Repairing crumbling mortar in stone walls is a relatively easy job, but it’s also quite tedious. The rotting and crumbling mortar is taken out and replaced with new mortar. The type of new mortar used is important and it’s generally determined by the condition of the stones and the type of the stones used to construct the wall. A bonding agent is typically used when new mortar is placed in the wall. Many foundations will be rotted in some areas while other areas have held up quite well.

The joints are investigated with a brick hammer by tapping it on them. If there is a hollow sound, then the mortar is replaced. The process is then repeated over and over again, which makes it tedious. In some cases, the dirt and mortar can be blasted out with a high-pressure garden hose. However, it’s important to make sure the stones aren’t disturbed. In most cases though, the old mortar is removed with a brick hammer or a pneumatic hammer.

Stone Foundation Repairs in Toronto

The crumbling mortar is usually removed from the top down and the wall is cleaned before new mortar joints are installed. It’s essential that the new mortar is placed behind the stone to make sure its bale to bond and bind. Some homeowners with stone basements try to support the floor joists and/or beams as they believe this will help take the weight off the wall. But in reality, this won’t stop the wall from crumbling or moving.

This is because a block or stone wall receives lateral strength from the pressure or weight that’s applied down onto it. If the weight is taken off of the wall there’s a better chance it will fall in, buckle, or move. Of course, the best way to preserve a home’s stone foundation is to replace any crumbling mortar. But until you can get it fixed, you should try to make sure that any ground water around the building’s foundation runs away from it at ground level. This is because dirt is moved by water and it can also move mortar. When you get your foundation repaired usually depend on your schedule and financial budget. When it comes to the cost, you may find it’s less expensive to repair the damage during the winter months when contractors usually aren’t as busy and they may be looking for work.

Have The Condition Of Your Stone Foundation Inspected

If your basement is in really bad shape you may want to consult a professional contracting company to have your foundation repaired or the basement underpinned. Nusite Group offers a free in-home inspection and estimate on all stone foundation issues and consult with you on the several improvement options that may be available to you so you can make an informed choice.

Foundation cracks in Toronto are common due to the age of the housing in the GTA, as well as the weather (rain-snow-freezing-thawing).  Foundation cracks develop over time for a variety of reasons and leads to basement water leaks as water makes its way into through the foundation.

Water Penetration Trough Concrete Floor

Foundation cracks may not seem appear too serious at first, but there’s always a chance they could cause some damage further down the road. This is why it’s a good idea to have them inspected by a professional. Horizontal and/or vertical cracks in a foundation usually won’t threaten the building’s structural integrity as cracking from earth settlement below the foundation and drying of drywall tape or concrete typically won’t cause a problem.

Foundations Move and Shift Over Time

Buildings continually move when the framing shifts and the earth contracts and expands due to heat and humidity fluctuation. Most homeowners won’t even notice the movements since they’re so small, but older homes were often constructed with a reliance on friction and gravity to hold the components of the building in place. The structure can weaken over time and then settle and spread. If the problem isn’t looked after, the building could collapse under its own weight. However the components are all tied together in newer buildings to form a single unit to stop this from happening.

Some structural defects are often hidden inside of walls and under the ground while others are more obvious. Since damage to the structure can be caused by moisture you should inspect the foundation if water from any source is running to it. If the foundation has been penetrated by water it’s generally due to a drainage problem. Salt will wash through a foundation and the rebar and wire mesh will rust away. When this happens the concrete will crumble as the foundation fails.

Leaks in plumbing, doors, windows and/or siding can cause rotting in wood and this can damage a structure’s integrity as the wood can turn to dust. If you find any rot in the trim around doorframes or windows or in there could be some hidden damage. If wood is untreated it may become moist due to contact with earth or concrete and start rotting on the inside. This is often a problem supports and columns for porches and decks.

If termites are present the wood can quickly turn to powder and when a wooden structure is touching the ground there’s usually some hidden damage. The easiest place to visually see any structural damage in a building is the top floor as shifting caused by rot or the movement of the foundation is more pronounced on the top level. Door and window frames will move more on a higher level than a lower one. If the higher levels have uneven floors it’s usually because the structure below isn’t properly supported.

Inspecting For Foundation Cracks

One way to check for structural problems is to inspect the corners of door and window frames with a carpenter’s square. If you find they’re not square it could be because there’s been structural movement below. Be aware that improper installation of the window or door could result in the corners not being square. If just one window or door frame isn’t square this is the likely cause since structural movement will generally affect more than just one frame.

You can check for uneven floors by placing a marble on the floor and see if it rolls. A slightly uneven floor isn’t necessarily bad news since some foundations are designed to ride the movement of the soil the same way a ship rides the waves. Buildings with these types of foundations may not always be perfectly even at all times. But if the floor is sloping in more than one direction then you should have it checked out.

When there’s structural movement it can result in cracking and the cracks can more or less tell the direction and location of the force which caused them. A crack shaped like a V could indicate upward-moving pressure. Upward-moving forces can happen when the soil expands and when the level of moisture is increased in the earth beneath foundations, patios, driveways and sidewalks. Float walls are usually built into basements of structures erected in expansive soil and the float wall is designed to expand and contract with the movement of the soil. If the walls are rigid the force of the expanding soil can push on them and damage the floors above.

Downward Pressure

A downward force will create a vertical crack which is wider at the bottom than the top and the force often originates from subsidence of the soil located below the building’s foundation. A structure can also be damaged by outward or inward force. Horizontal cracks usually aren’t serious, but if the surface below or above the crack has been forced outward or inward there could be problems. Inward or outward pressure can be the result of improper backfill, pressure of moving water and earth, or vehicle traffic that is too close to the foundation.

If you can determine the direction and lace of the force which has caused the cracks then it’ll be easier to find the source. If the damage is hidden though, it can be very hard to determine and costly to repair as floors, ceilings and walls may need to be opened to reveal the damage. It’s also possible you won’t realize there’s any damage until the structure eventually fails.

Foundation Tips When Buying a Home

When buying a home, it’s recommended that you inspect the patios, driveways and sidewalks to see if they’re sunken, heaved, cracked or twisted. If they are then the property may have expansive soils. If the foundation and other structures have been built for the conditions and water is routed away from concrete pads and the foundation you should find little indication of any concrete damage. Remember that most homes erected on expansive soils generally show some defects due to the constant expansion and contraction of the earth. It’s a good idea to have your home inspected if you’re unsure of any damage or contract a structural engineer for a professional opinion.

Have a questions about a crack in your foundation?  Nusite Waterproofing serves Toronto and the surrounding GTA.  We offer a free in-home inspection and estimate and can advise on how to repair your foundation crack.  Contact us here today to schedule an appointment.

Toronto home with vertical crack in foundationPoets, lyricists, and other writers love the metaphor of the crack in the foundation, something that is small but the forerunner of pathological damage. A crack in your foundation is information—it is telling you something, and you must invest the time to figure it out.  It may turn out to not be a big problem, but it demands assessment.  It’s usually best to call in a specialist to make this assessment.  If you’re hesitant that they will try to sell you a suite of services and repairs, remember you can always get a free estimate or just say “no,” but that one thing is for certain—a crack, once present, will not go away and requires intervention.

It’s usually best to call in a foundation specialist to make this assessment as a foundation crack can be totally normal, or can be an indicator of something serious.  If you’re hesitant that they will try to sell you a suite of services and repairs, remember you can always get a free estimate or just say “no,” but that one thing is for certain—a crack, once present, will not go away and may indicate a more serious problem with your foundation.

HYDROSTATIC_PRESSURE (1)

Here in Toronto, foundation cracks are quite common.  Many foundation cracks are simple from shifting foundations and aging homes “settling” over time.  While others are from shoddy construction from the start or an environment surrounding your foundation that is contributing to its erosion.  As you can see, sometimes it’s nothing but other times it can be serious.

Even if the foundation crack is not serious, it can still cause water issues and can lead to foundation erosion over time if water is allowed to continuously channel through your foundation into your basement.

So, let’s take a look at some of the most common information—the most common causes—of basement foundation cracks.

 

Concrete Contraction

Concrete is a mixture of cement, water, and aggregate.  It is poured and then dries and cures.  Early in the curing stage, the concrete enters its plastic state.  In this state, it is still very moist, but it continues to lose moisture during the curing process.  Steve VandeWater, in his paper “Why Concrete Cracks,” illuminates, “because concrete is a very rigid material, this shrinking creates stress on the concrete slab.  As the concrete shrinks, it drags across its granular subgrade.  This impediment to its free movement creates stress that can literally pull the slab apart.”  He continues, “when the stress becomes too great for the now hardened concrete, the slab will crack in order to relieve tension.”

VandeWater points out that these plastic-state cracks are almost sure to occur near obstacles, objects placed in the concrete slab, such as drains, plumbing fixtures, etc.  The concrete has no ability to shrink around these objects.

 

Contraction cracks not a disaster

Fortunately, though some cracks due to the contraction of concrete during its curing process are inevitable, they aren’t likely to cause serious structural damage.  They’re mostly a nuisance, providing a gateway for things like water leaking or insects.

 

Exterior step crack Toronto home

Exterior step crack

Settlement

A second big reason for basement cracks is your house settling into the soil.  Daniel Friedman is a construction worker who discusses this issue.  He says that floor slabs need to be poured into “compacted fill” as opposed to “soft fill.”  To explain what this means, he clearly illustrates, “my first job in construction was raking a huge dirt pile out to ‘level’ inside of an already poured and built footing and masonry block foundation wall.  Once the dirt was roughly ‘level’ via my hand rake, the builder went ahead and poured his floor slab.  ‘Compacted fill’ was not in our vocabulary.”

Floor slabs not poured in this manner are more vulnerable to settling into the soil, and in the vocabulary of the business, “floating,” moving as the soil moves.

Yet, it’s just as often that the culprit is not construction workers at all.  Mother Nature will damage your foundation if you give her half a chance.  Too much rain will cause the rising groundwater to squeeze the house’s foundation.  The bad news is that dry periods are problematic, too, since dry soil shrinks, in turn causing you foundation to settle.

In Winter, groundwater freezing also causes pressure on your foundation, pressure that may lead to cracking.

One thing to do to attempt to combat the sorts of pressure described above is to improve the tensile strength of your concrete.  Tensile strength is the ability to withstand force that could pull something apart.  Strange though it might seem, concrete actually has fairly low tensile strength.  Improving it can be a matter of a contractor adding rebar of fiber to the concrete.

 

Horizontal crack in Toronto foundation home

Horizontal Crack

Horizontal Cracking

If the cracks you observe are horizontal, you should take them that much more seriously, since they are indications of serious structural problems.  Consultant Gary Fuller explains, “if the foundation does not provide enough lateral support, the walls will deflect inward and create horizontal cracking.”

Mike Holmes, host of the TV show “Holmes Inspection,” alerts us that horizontal cracking higher on the walls calls from water or frost, as “water from your downspouts or sump pump saturates the area, it freezes and exerts pressure on the basement wall.”

While there may not be one cure for basement cracks or one correct course of action, just be sure not to ignore the problem.  Take a lesson from the poets and don’t let the cracks spread and leave you on a foundation of rubble.

Spotting subsidence problemsMany people worry about the long term costs and safety of buying a house with subsidence. Subsidence refers to unstable building foundations which cause parts of the structure to slowly sink downwards. As with all building issues, levels of subsidence vary greatly, with home owners having to endure great costs and distress in more severe cases. If you are a landlord, subsidence is never a welcome sign for functional property management, so if you suspect your property has subsidence or the problem is getting worse, spotting the signs early may help you avoid larger worries down the road.

Causes

The most common causes of subsidence are due to geological, natural causes. Clay soils are a common culprit for the problem as they lock in moisture for long periods of time which then causes it to expand. Once dried, it then shrinks, making the foundations of a building unstable. These soils are usually found along river banks so the location of your property can be a crucial factor in subsidence risk. Look for signs of subsidence after a long wet or dry spell. Tree roots can also dry out this clay and create a problem to a structure as the roots grow out of control. This accounts for more than half of all subsidence cases so it is important to maintain or chop down a large tree close to your property. Uneven soils also add to the issue, especially in areas which witness earthquakes and tremors on minor and major fault lines.

Spotting subsidence problems

 

Spotting subsidence

The key thing you should look for when spotting signs of subsidence are cracks. It can sometimes be hard to differentiate a subsidence crack to one which has been the simple result of time and seasonal changes such as frost. Look for interior and exterior cracks which taper diagonally downwards across wall surfaces. Another sign is to look for changes in wallpaper. Once you have ruled out damp as the cause, subsidence should be the next worry. Many cracks are hidden by wallpaper, so as the levels of your walls shift; ripples and hanging corners may appear in the paper. If these signs are spotted, also test your doors and windows in their frames to check for alterations. Unfortunately, monitoring your house for subsidence can be a lengthy process which is frustrating as the sooner the problem gets sorted, the less money and time you will have to spend on treating the problem.

How to repair subsidence problems

How to treat subsidence

Actually treating the problem of subsidence can be the most lengthy and distressful stage of the whole process if the issue goes unnoticed for some time.

The process of underpinning the entire structure may have to be implemented in the most severe cases which can cost homeowners thousands of pounds. The majority of properties with subsidence will not need to be fixed with such extreme lengths but it is always best to get your home thoroughly assessed. Although underpinning is a costly fix, the likelihood of subsidence is usually minimal, which will help towards insuring your property. Insuring a property with subsidence can be arduous although there are now many comparison websites which research the best deals for you.

Roots causing subsidence problem

In terms of tree roots, you will need the advice of an expert as to whether removing the roots from under the property will be a quick solution or a detriment to the project. Over the years, major root networks will have shifted the soil to create space. Once the roots are taken away, this space may soon fill up with water, which will add to your structural problems.

Another cause of unwanted water under your home is a burst or leaking pipe. Once this problem is determined, mending this can be a quick fix.