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.

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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.

Have Foundation Questions?

If you live in Toronto or the surrounding GTA, we offer a free in-home inspection and estimate for foundation cracks, basement waterproofing and related basement renovation projects.  You can contact us here.

Did you know that problems on your roof can lead to a leaky basement?

The roofing system on your house, which includes the shingles, eavestroughs, and drains, are meant to do one thing; to channel rain water from your roof and away from your foundation.  If the system is working properly, that’s exactly what it will do.  If it’s not, then rain water will begin to pool around your home’s foundation, eventually causing water problems in your basement.

Here in Toronto, the roofs on our homes are subject to some severe weather conditions.  The long Winters, with snow build up, thawing, then re-freezing, can really wear down your roof over time.  It’s important to schedule times throughout the year where you can inspect your roof system and make sure that it’s properly channeling water away from your foundation.

The infographic below provides a nice pictorial of potential problems you may come across when you examine your roof.  Take a few minutes of preventative maintenance to help avoid costly foundation repairs later on.  Have questions about channeling water away from your foundation?  Feel free to contact us here, we’re happy to help!

Roof Maintenance Infographic

 

Flooding in Toronto basementIt seems that weather conditions are becoming increasingly unpredictable in recent years, with many homeowners dealing with severe flooding for the first time. It’s the worst time to find out that your home insurance won’t adequately protect and compensate you.

This article can help increase your chances of making a successful insurance claim in the event of a flood.

 Are you at risk?

It’s easy to ignore potential problems such as flooding, especially if there are no obvious signs of previous flooding at the property and it isn’t a common problem area. Remember it’s not just homes located next to rivers and seas which are at risk, rising ground water, burst water mains, sewer overflows and rainfall can all cause unexpected and severe flood damage.

You won’t know your home’s vulnerability to flooding until it is too late, so if you’re concerned you can carry out a flood risk assessment on the property. Environmental agencies may also be able provide useful information about the flood risk in your area.

Take all reasonable steps to protect your property from flood damage. This could include sealing up a roof to ensure that there are no leaks, and by having proper drainage in the basement (handy guide here). This may reduce your flood risk and in turn could reduce the cost of your insurance premiums.

Research insurance policies

Insurance providers will offer different levels of flood cover in their policies. Basic policies will usually cover the architecture of the property, i.e. its exterior/interior walls, floors, ceilings etc. Any adjoining buildings such as garages or sheds will also need to be insured separately.

Often you’ll need to upgrade the policy in order to obtain protection for your possessions within the property, including furniture, furnishings and electrical devices.  Insurers will conduct their own flood risk assessment of the property, and obviously the cost will depend on the flood risk, so having the results of your own independent assessment can be highly empowering when negotiating.

Making a Claim

If you are hit with flood damage then ensure that you record all damage with photographic or video evidence, marking water lines on the wall if they begin to recede.  If damage needs urgent professional repair then seek advice from your insurance company immediately. The insurer may be able to provide reputable and reliable tradespeople if you are unable to find the right person for a particular repair. Keep the receipts of this work so you can present it to your insurer, and they may be able to reimburse you. The insurer may be able to provide reputable and reliable tradespeople if you are unable to find the right person for a particular repair.

When communicating with the insurer keep records of all correspondence, including making notes regarding any telephone communications. When you make a claim inevitably an insurer will appoint a loss adjuster to reduce the insurer’s financial liability. An insurance loss assessor helps individuals to make insurance claims. A loss assessor works on behalf of the claimant to maximise their payout.

Flooding can cause significant damage to a home and everything contained within it, so take steps to secure your home and consider appointing an insurance loss assessor when making flood claims to maximise your pay-out.

Have questions about mold and water damage and how your home insurance works?  Contact Nusite Group today and speak to one of our specialists.  Nusite Group has been serving Toronto and the GTA for over 30 years.

Foundation slab in Toronto basementDo you have cracks appearing in your foundation walls?  There can be many reasons for cracks to appear, some may be harmless, while others may be signs of serious problems.

A foundation is the substructure on which a building rests. In Canada this is usually reinforced concrete although some elevated homes may be exceptions. The concrete sub-base can take two different forms. It could be a series of strips mirroring the walls above, or a solid sheet.

The correct application depends on the soil type. If it is stable, the strip method may suffice. However if the soil is clayey and likely to heave during wet periods, then the correct solution is a concrete “raft” that insulates the structure overhead from the movement that occurs below.

The Common Problem

Many builders design foundations on the basis that they will be stable once laid. Over time, outside forces make shift and put stress on the concrete structure:

  • The earth beneath the foundations settles because it was not properly compacted in the first place and ground water flows in through the gap
  • Earth movement occurs as a result of seismic events, mining activity or construction work on an adjacent site
  • The ground expands and contracts during alternating wet and dry seasons, especially if it has a clay component

When foundations move and crack below, this movement transfers to the structure above where masonry courses separate. It is most likely to be evident in the vicinity of weaker points like corners and above window and door frames.

Foundation crack Toronto home

Warning Signs

Unless caused by seismic activity, masonry cracking is usually a gradual process that occurs almost imperceptibly. Early indications can include:

  • Doors and windows that jam up in wet periods but begin to rattle in the wind when the weather’s dry
  • Cracks stepping up the masonry courses or appearing horizontally through bricks
  • In extreme cases, distorted walls and tilting chimneys

It goes almost without saying that these problems must be dealt with before serious structural damage occurs.

Remedial Action

While the ostensible cause of foundation cracking is ground movement or soil erosion, the true reason is that the foundation may be inadequate for local circumstances, or was earth around it was not settled properly before creating the foundation. Short of tearing down the structure the only practical solution is to strengthen the foundation. Foundation engineers achieve this with a variety of solutions that include steel or helical peers, plate and tie anchors, hydraulic lift slab piers and concrete underpinning.

In Summary

Cracks appear in foundations for two related reasons. Either the substructure is inadequate, or an event occurred outside the design specification. While the settlement may be slight and the visible evidence purely cosmetic, it may be the beginning of a far more serious problem if left untreated.

Some foundation cracks may not be an indicator of serious foundation problems, while others may signal the start of serious foundation problems.  If you have foundation cracks and aren’t sure how serious they are, feel free to contact us, we’re happy to answer any questions you may have.

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.