The Ultimate Guide to Post Tension Cables & Why They Are Used

Post-tension cables can be an integral component of construction, offering enhanced strength, flexibility, and sustainability in the design and execution of structural systems. Known for theirpost tension cable guide in calgary capacity to support large spans and heavy loads, these cables are commonly used in structures such as high-rise buildings, bridges, and parking structures. 

Post-tensioning technology revolves around the concept of actively reinforcing concrete, enhancing its inherent compressive strength and compensating for its lack of tensile strength. This reinforcement process involves tensioning steel cables within a concrete element and anchoring them after the concrete has cured, thereby compressing the concrete and improving its overall structural performance.

Explore the pivotal role of post-tension cables in Calgary's architectural landscape. These engineering marvels are not just components; they're the keystones of modern construction, shaping the city's skyline with strength and elegance. But why are they so crucial, and how can they influence your real estate decisions? Let's uncover the secrets behind these structural powerhouses AND potential liabilities. 

What Are Post Tension Cables?

These cables are strong steel tendons which, when tensioned and anchored to concrete, are designed to provide increased structural integrity and resilience. 

Post tension cables, composed of high-strength steel tendons, are used within concrete to enhance strength and durability. Unlike conventional reinforcing bars, these cables are tensioned after the concrete has cured, squeezing the slab and keeping it in a perpetual state of compression. 

This might sound like a tight squeeze, but it's precisely what gives modern buildings their ability to reach new heights and span wider spaces without the need for bulky supports.

The Role of Post Tension Cables in Modern Construction

At the heart of previous of tension cables, a key player in modern architecture that's as fascinating as it is functional. But what are post tension cables, and why should you, as a prospective homeowner or an industry professional, care?

In this deep dive, we'll unravel the inner workings behind these high-strength steel strands that once stretched the boundaries of building design. Whether you're looking to buy a condominium or just here to indulge your curiosity about past construction trends, understanding the role of post tension cables is crucial if you ever want to enter into ownership of a building with them.

So, let's lay the foundation for a robust knowledge of how Calgary's condominiums were once built to last, one cable at a time.

What Are Post Tension Cables Used For?

Post tension cables are used for everything from supporting the floors of expansive shopping centers to bridging the gaps in a draw-dropping cantilever, post tension cables are integral to structures that require long spans without columns interrupting the space.

Consider the open-concept designs that are all the rage in Calgary's condominiums and offices. Post tension cables allow for broader, open spaces within buildings, free from the clutter of additional supports. 

They’re also used in constructing durable, long-lasting foundations that stand firm against the challenges by diverse soil conditions. PTC can be found in a wide variety of applications from commercial complexes to condominiums that host hundreds. Post tension cables can help provide the structural integrity that makes diverse designs possible.


How Do Post Tension Cables Work?

To truly appreciate the marvels of Calgary's architectural feats, it’s important to understand how post tension cables work. It's like a symphony where every element plays a critical role in the structural integrity of the building. 

Imagine the concrete slab as a block of hard cheese and the post tension cables as strings running through it. When these "strings" are pulled tight, they compress the "cheese," making it hold together even more firmly.

This tensioning process occurs after the concrete has hardened. The cables, threaded through ducts in the concrete, are stretched using hydraulic jacks with forces equivalent to several tons. Once the desired tension is reached, they are anchored in place, and the concrete slab is kept in a state of compression. This compression is the secret to why buildings constructed with post tension cables can withstand the pressures of heavy loads, seismic activity, and even Calgary's expansive clay soils that swell and shrink with moisture changes.

By understanding this process, we peel back the curtain on the kind of robust construction that's becoming a standard in Calgary's real estate. It’s a method that ensures not just longevity and flexibility, but also safety and efficiency, echoing the city's spirit of resilience and innovation.

What Do Post Tension Cables Look Like?

When we talk about what post tension cables look like, you might imagine them as just metal wires running through concrete. But there's more to their story. Each cable, or tendon, is a composition of multiple steel strands, each about the diameter of a pencil. These strands gleam with the promise of strength, coated in a corrosion-inhibiting grease and encased in a plastic sheath for protection.

These tendons are often seen bundled together, making them look like metallic ropes ready to perform an act of architectural acrobatics. Before tensioning, they lay dormant within the slabs, unassuming and unnoticed. Once tensioned, they are hidden within the concrete, like veins within the body, essential yet invisible, providing the life force for the structure's stability.

Visualizing these components is crucial when considering the aesthetics of Calgary’s contemporary architecture. They allow for thinner slabs and fewer beams, resulting in cleaner lines and more elegant profiles in buildings. The design possibilities are vast, with the promise of open, airy spaces that invite light and life into urban spaces.

How Are Post Tension Cables Installed?

It's a meticulous and precise operation that begins with laying out the cables along the predetermined paths in the concrete forms before the pour. These paths are carefully engineered to ensure that the tension is distributed evenly throughout the concrete slab.

Once the concrete is poured into the plastic sheaths and achieves sufficient strength, the tensioning process begins. Technicians use hydraulic jacks to stretch the cables, pulling them tight with forces measured in thousands of pounds. This is a critical stage where precision is paramount––even a slight miscalculation can affect the integrity of the structure.

After tensioning, the cables are anchored to the outer edges of the concrete, and the tension is transferred to the concrete, compressing it and increasing its load-bearing capacity.

In Calgary, where every season can bring a different challenge to the integrity of a structure, this process is a testament to the city's commitment to quality and durability. Post tensioning installation is a choreographed dance between strength and flexibility, ensuring that homes and office buildings can withstand the test of time and the harshness of the elements.

Post tension cables in calgary skyline

What Apartments in Calgary Have Post Tension Cables?

Below is a comprehensive list of buildings in Calgary that we have recorded as having post tension cables. Please note this information is deemed to be accurate but could have inaccuracies for up to date information or confirmation of the existence of post tension cables, reach out to your REALTOR® to confirm. If you aren't working with a REALTOR®, contact our team 587-578-7653 we have helped over 1,000 buyers in Calgary and surrounding area and have agents who can provide in depth knowledge on the post tension cables in our city. 

Building NameAddressYear Built
Acadia Manor 366 94 Avenue SE 1978
Alberta Manor 330 15 Avenue SW 1979
Anderson Place 11620 ELBOW Drive SW 1977
Arbour Grove 55 Arbour Grove Close NW 1997
Arbour Lake Landing 950 Arbour Lake Road NW 2000
Arlington Place 727 56 Avenue SW 1982
Aurora at Chinook 790 KINGSMERE Crescent SW 2000
Bankpark Place 2401 16 Street SW 1978
Barclay at Riverwest 1088 6 Avenue SW 2003
Bayshore Park 2425 90 Avenue SW 1981
Bella Casa 1727 54 Street SE 2010
Bella Lusso 1000 Centre Avenue NE 2006
Bella Vista 1800 14A Street SW 2011
Bethlehem Square 828 4A Street NE 1977
Bonavista Estates II 3121 LAKE FRASER Green SE 2004
Bowside Manor 110 2 Avenue SE 1978
Brae Glen 202 BRAEGLEN Close SW 1973
Brae Glen Court 201 BRAEGLEN Close SW 1972
Braebourne 1712 38 Street SE 1981
Brava 55 SPRUCE Place SW 2005
Bridgeland Crossing 46 9 Street NE 2016
Bridgeview Apts 420 3 Avenue NE 1982
Bridgeview Heights 712 4 Street NE 1981
Bridlecrest Pointe 16969 24 Street SW 2008
Brisbois Place 333 2 Avenue NE 1981
Bristol Manor 1020 14 Avenue SW 1981
Brookpark Gardens 10120 Brookpark Boulevard SW 1977
Cambrain Sq.south 545 18 Avenue SW 1982
Cambridge Square 540 18 Avenue SW 1982
Cameron Court 1313 CAMERON Avenue SW 1980
Canvas at Millrise 23 MILLRISE Drive SW 2008
Canyon Pines Condominums 13045 6 Street SW 1982
Caramoor 1540 17 Avenue SW 2000
Carriage Villas 1229 Cameron Avenue SW 1981
Cedar Spring Gardens 69 CEDAR SPRINGS Gardens SW 1983
Centre 20 110 20 Avenue NE 1982
Champagne 201 Quarry Way SE 2014
Chaparal Villas 11 CHAPARRAL RIDGE Drive SE 1999
Chateau La Caille 200 LA CAILLE Place SW 1999
Chelsea Lofts 2214 14A Street SW 1978
Chelsea Terrace 1732 9A Street SW 1979
Chinook Manor 521 57 Avenue SW 1976
Chinook West 732 57 Avenue SW 1981
Chocolate 188 15 Avenue SW 2006
Churchill Towers 1027 CAMERON Avenue SW 1962
Citadel Pointe 1000 CITADEL MEADOW Point NW 2000
City View Manor 1107 15 Avenue SW 1977
College Gardens 200 LINCOLN Way SW 1995
Colours 135 13 Avenue SW 2009
Compass Erin Woods 73 ERIN WOODS Court SE 2006
Copperfield Park II 755 Copperpond Boulevard SE 2014
Copperwood 14 HEMLOCK Crescent SW 2004
Country Village 120 COUNTRY VILLAGE Circle NE 2008
Covenant House 222 EAGLE RIDGE Drive SW 1967
Cozart 1001 14 Avenue SW 1981
Cypriana Towers 537 14 Avenue SW 1979
Dana Village 1818 SIMCOE Boulevard SW 1997
Darlington Arms 317 14 Avenue SW 1970
Discovery Hill 215 2 Street NE 1979
Discovery Place 354 3 Avenue NE 1979
Discovery Point 354 3 Avenue NE 1979
Discovery Pointe 1121 6 Avenue SW 2003
Doral Manor 1311 15 Avenue SW 1981
Dorchester Square 924 14 Avenue SW 1981
Dorchestor Square 924 14 Avenue SW 1981
Dunhill Estates 1414 5 Street SW 1981
Eagle View 717 4A Street NE 1983
Eau Claire Estates 500 Eau Claire Avenue SW 1981
Eightwelve 812 14 Avenue SW 1977
Elliston Park 6224 17 Avenue SE 1999
Emerald Stone 836 15 Avenue SW 2004
Encore 77 SPRUCE Place SW 2008
Equinox 2010 35 Avenue SW 1982
Erlton Terrace 3606 ERLTON Court SW 1981
Estate 720 13 Avenue SW 1980
Euro 706 15 Avenue SW 1964
Evergreen Manor 1919 36 Street SW 1981
Evergreen Pointe 2371 EVERSYDE Avenue SW 2005
Evolution 510 6 Avenue SE 2017
Executive Manor 235 15 Avenue SW 1981
Expresso 355 5 Avenue NE 1977
First 619 confluence Way SE 2015
Fish Creek Pointe 2518 FISH CREEK Boulevard SW 2004
Five Harvest Plaza 108 3 Avenue SW 1977
Foothills Village 1540 29 Street NW 1978
Fortress 4944 DALTON Drive NW 1977
Fountaine Bleau Estates 215 14 Avenue SW 1980
Foxboro House 234 5 Avenue NE 1979
Gallant Ridge 211 Aspen Stone Boulevard SW 2008
Gateway Garrison Green 5605 HENWOOD Street SW 2006
Gateway Marda Loop 1811 34 Avenue SW 2002
Gateway Shawnessy 260 Shawville Way SE 2001
Gateway Southcentre 11811 Lake Fraser Drive SE 2006
Glenbrook Meadows 2850 51 Street SW 1997
Glengarry Court 1915 26 Street SW 1981
Glengarry House 1917 24A Street SW 1981
Glenmore On The Parc 80 Galbraith Drive SW 1971
Grandville Place 616 15 Avenue SW 1978
Grapevine 1202 13 Avenue SW 1981
Grosvenor House_Oliver 1240 12 Avenue SW 1981
Groves of Varsity 24 Varsity Estates Circle NW 2015
Haiku 1301 17 Avenue NW 1980
Hallmark Estates 1323 15 Avenue SW 1979
Hampstead Estates 1140 15 Avenue SW 1979
Hampton Court 133 25 Avenue SW 1976
Hamstead Estates 1140 15 Avenue SW 1979
Harcourt Estates 1334 14 Avenue SW 1981
Hays Farm 8948 ELBOW Drive SW 1973
Heritage Manor 9500 OAKFIELD Drive SW 1979
High Pointe Estates 354 2 Avenue NE 1981
Highcastle 78 PRESTWICK Gardens SE 1999
Highland Estates 210 86 Avenue SE 1970
Highland Park 70 GLAMIS Drive SW 1981
Highland Terrace 431 1 Avenue NE 1982
Hilltop House 231 Heritage Drive SE 1970
Holly Park 300 MEREDITH Road NE 1979
Holly Point 320 MEREDITH Road NE 1981
Hong Kong Plaza 128 2 Avenue SE 1990
i.D. Inglewood 1020 9 Avenue SE 2020
Indigo Sky 7210 80 Avenue NE 2013
Kensington Court 314 14 Street NW 1969
Kensington On The Park 1222 Kensington Close 1978
Kensington Prk Plaza 1222 KENSINGTON Close NW 1978
KeyNote 220 12 Avenue SE 2010
Killarney Courts 2218 30 Street SW 1982
Killarney Manor 1900 25A Street SW 1982
Killarney Meadows 2211 29 Street SW 1990
King Manor 1829 11 Avenue SW 1965
Lancaster Gate 1312 13 Avenue SW 1969
Landmark Aspen 3730 50 Street NW 1978
Landmark Estates 3719B 49 Street NW 1978
Landmark Gardens 333 GARRY Crescent NE 1980
Landmark West 3719B 49 Street NW 1978
Laureate Place 2011 UNIVERSITY Drive NW 1991
Le Germain Residences 108 9 Avenue SW 2009
Leaton Place 1733 27 Avenue SW 1992
Lewis Lofts 240 11 Avenue SW 1911
Liberte 804 3 Avenue SW 1999
Lighthouse Landing 31 COUNTRY VILLAGE Manor NE 2010
Livingstone House 821 3 Avenue SW 1978
London at Heritage Station 8710 HORTON Road SW 2008
Luna 1111 10 Street SW 2012
Manchester Place 5720 2 Street SW 2005
Manhattan 1117 1 Street SW 1912
Marda Station 2212 34 Avenue SW 1998
MARK on 10th 901 10 Avenue SW 2016
Mayland Heights 30 MCHUGH Court NE 1981
Mayland Terrace 30 MCHUGH Court NE 1981
McCall Landing 181 Skyview Ranch Manor NE 2017
Mi Casa 635 4 Avenue NE 1981
Midnapore Manor 15320 BANNISTER Road SE 2002
Milano 48 PANATELLA Road NW 2011
Mission Royale 626 24 Avenue SW 1980
Monarch at McKenzie Towne 310 MCKENZIE TOWNE Gate SE 2011
Montage 1111 13 Avenue SW 1981
Monticello Estates 1309 14 Avenue SW 1979
Mount Royal Courts 1721 13 Street SW 1982
Mount Royal Grande 838 19 Avenue SW 2002
Mount Royal Terrace 1215 CAMERON Avenue SW 1981
Mountainview Estates 3420 50 Street NW 1976
Nine Eight Hundred 9800 HORTON Road SW 1982
No Name 323 20 Avenue SW 2013
Noran House 1814 18 Street SW 1990
Nova 1118 12 Avenue SW 2008
Odyssey 10 Coachway Road SW 1978
Odyssey Towers 10 COACHWAY Road SW 1978
Orchard Sky 302 Skyview Ranch Drive NE 2016
Ovation 99 SPRUCE Place SW 2010
Oxford Parc 525 56 Avenue SW 1983
Palace Royale 629 Royal Avenue SW 1969
Palisades 340 14 Avenue SW 1972
Panamount Place 70 PANAMOUNT Drive NW 2004
Panorama Pointe 60 PANATELLA Street NW 2008
Panorama West 130 PANATELLA Street NW 2013
Park 300 Pallisades 339 13 Avenue SW 1971
Park Estates 220 13 Avenue SW 1982
Parkdale Point 3402 PARKDALE Boulevard NW 1980
Parkside Terrace 1208 14 Avenue SW 1979
Parkview Terrace 60 38A Avenue SW 1984
Parkwood Towers 2512 1 Avenue NW 1969
Patterson Heights 305 Village Mews SW 1986
Pavilions 369 ROCKY VISTA Park NW 2004
Pearce Gardens 1414 17 Street SE 2003
Plaza 14 1505 8 Avenue NW 1980
Point Mckay 145 point Drive NW 1979
Point Mckay Phase I 145 Point Drive NW 1981
Pointe of View - Applewood 1620 70 Street SE 2004
Pointe Of View Harvest Hills 20 HARVEST ROSE Park NE 1998
Pointe Of View West Point Plaza 16320 24 Street SW 2004
Polo Terrace 126 14 Avenue SW 1999
Pontefino 990 CENTRE Avenue NE 2006
Prestwick Place 115 PRESTWICK Villas SE 2008
Prince's Island Estates 400 Eau Claire Avenue SW 1995
Princes Crossing 738 3 Avenue SW 1981
Prospect Place 4908 17 Avenue SE 1977
Providence at Bankview 2307 14 Street SW 2007
Raven Ridge Gardens 92 Saddletree Court NE 2008
Red Haus 60 Royal Oak Plaza NW 2007
Redwood Manor 1633 26 Avenue SW 1978
Refrew House 611 8th Avenue NE 1977
Regal Court 722 4A Street NE 1979
Regal Manor 819 4A Street NE 1981
Regal Ridge 350 4 Avenue NE 1981
Regal Terrace 809 4 Street NE 1979
Regency Court 222 5 Avenue NE 1978
River Grande Estates 60 24 Avenue SW 2001
River's Edge 220 26 Avenue SW 1978
Riverfront Pointe 315 3 Street SE 2009
Riverhill Gardens 635 Marsh Road NE 1981
Riverscape 225 25 Avenue SW 1984
Riverside Towers I 145 Point Drive NW 1980
Riverside Towers II 80 POINT MCKAY Crescent NW 1981
Riverstone 318 26 Avenue SW 1982
Riverview Estates 2611 1 Avenue NW 1981
Riverview Place 2204 1 Street SW 1981
Riverwest 1088 6 Avenue SW 2003
Rockland Place 1731 9A Street SW 1982
Rocky Mountain Court 221 6 Avenue SE 1980
Rondo 931 2 Avenue NW 1978
Rosemount Place 103 10 Avenue NW 1980
Rosewood Estates 540 14 Avenue SW 1978
Roxboro House 330 26 Avenue SW 1977
Royal Oak 1001 13 Avenue SW 1981
Sanderson Ridge 2330 FISH CREEK Boulevard SW 2017
Sasso 1410 1 Street SE 2006
Scarboro Park 1625 14 Avenue SW 1978
Sierra's Of Country Hills 728 COUNTRY HILLS Road NW 2001
Sierra's Of Tuscany 223 Tuscany Springs Boulevard NW 2001
Sierra's West Ii 6868 Sierra Morena Boulevard SW 1998
Silverwood On The Park 8604 48 Avenue NW 1981
Simmering Court 930 18 Avenue SW 1983
Skymills 240 Skyview Ranch Road NE 2014
SkyWest Condominiums 155 SKYVIEW RANCH Way NE 2013
Solea 15304 Bannister Road SE 2008
Somerset 6000 203, Somervale Court SW 2001
Somerset Crossing 2000 SOMERVALE Court SW 2001
Sonesta House 523 15 Avenue SW 1978
Sonoma Place 310 8 Street SW 1981
South Pointe 4975 130 Avenue SE 2004
Stella 1110 11 Street SW 2006
Sterling Place 1234 14 Avenue SW 1978
Stonecroft At Arbour Lake 88 Arbour Lake Road NW 2008
Stonehaven 735 12 Avenue SW 1978
Sunalta House 1335 12 Avenue SW 1978
Sunalta Park 1602 11 Avenue SW 1980
Sunnyside 808 4 Avenue NW 1981
Sunrise 116 3 Avenue SE 1981
Sunrise Pointe 165 Manora Place NE 1999
Suntree Place 2909 17 Avenue SW 1982
Suntree Villas 659 4 Avenue NE 1981
Sunward Estates 929 18 Avenue SW 1983
Taralake Place 355 Taralake Way NE 2013
Tarjan Pointe 1111 6 Avenue SW 2005
Taymar 317 19 Avenue SW 1981
Terra Del Sol 1414 12 Street SW 1981
Terraces On Broadcas 220 VILLAGE Terrace SW 1987
The Armory 145 BURMA STAR Road SW 2016
The Axxis 650 10 Street SW 2000
The Casel 2505 17 Avenue SW 2011
The Conservatory 527 15 Avenue SW 2000
The Davenport 1011 12 Avenue SW 1981
The Edison 10 Walgrove Walk SE 2017
The Estate 720 13 Avenue SW 1980
The Fortress 4944 DALTON Drive NW 1977
The Grandeur 1920 14 Avenue NE 1999
The Grandview 228 26 Avenue SW 2000
The Guardian 1122 3 Street SE 2015
The Hallmark 835 19 Avenue SW 1979
The Huntsman 1334 13 Avenue SW 1980
The Landmark 3719 49 Street NW 1978
The Lofts On 17th 610 17 Avenue SW 1979
The Mackenzie 114 15 Avenue SW 2000
The Manhattan 1919 17 Avenue SW 1982
The Manhatten 1919 17 Avenue SW 1982
The Mariposa 626 15 Avenue SW 1980
The Marquis 1108 6 Avenue SW 2001
The Mission Gate 509 21 Avenue SW 2006
The Monoco 1315 12 Avenue SW 2000
The News 114 Village Heights SW 1987
The Park 303 13 Avenue SW 2015
The Pavilions of Eau Claire 777 3 Avenue SW 1998
The Phoenician 5201 DALHOUSIE Drive NW 1998
The Pointe at Prestwick 10 PRESTWICK Bay SE 2006
The Ravenwood 1334 12 Avenue SW 1980
The Renaissance 1718 14 Avenue NW 2001
The Richmond 111 14 Avenue SE 1981
The Riverfront 550 RIVERFRONT Avenue SE 2015
The Serenity 924 18 Avenue SW 1968
The Strahan 1836 12 Avenue SW 1978
The Terraces Of Broadcast Hill 212 VILLAGE Terrace SW 1987
The Vineyards 130 25 Avenue SW 1981
The Wedgewoods 20 DISCOVERY RIDGE Close SW 2006
Tiboron Court 2400 15 Street SW 1980
Trafalgar House 22 RICHARD Place SW 2002
Treo at Beddington 8200 4 Street NE 2007
Union Square 215 13 Avenue SW 2009
University City 3830 BRENTWOOD Road NW 2014
Urban Street 505 19 Avenue SW 1969
Valhalla Ridge 2022 CANYON MEADOWS Drive SE 2001
Valhalla View 1441 23 Avenue SW 1997
Valleyview Park Place 6303 VALLEYVIEW Park SE 2000
Vantage Pointe 1053 10 Street SW 2006
Varsity Acres 4603 VARSITY Drive NW 1978
Varsity Towers 4555 VARSITY Lane NW 1978
Varsity Village 4001 49 Street NW 1976
Varsity Villas 4001A 49 Street NW 1977
Ven of Kensington 823 5 Avenue NW 2015
Venezia Estates 210 25 Avenue SW 1978
Verve 615 6 Avenue SE 2019
Vetro 210 15 Avenue SE 2008
Villa d'Este 10221 TUSCANY Boulevard NW 2007
Village 301 VILLAGE Mews SW 1987
Viridian 20 Sage Hill Terrace NW 2017
Vista View 5204 Dalton Drive NW 1981
Vive 1603 26 Avenue SW 1975
Waterford of Bridgeland 647 1 Avenue NE 1981
Waterfront 222 RIVERFRONT Avenue SW 2012
Wedgewoods of New Discovery 10 Discovery Ridge Close SW 2005
Wellington Estates 1330 15 Avenue SW 1973
Wellington Place 903 19 Avenue SW 1968
Westbow 1304 15 Avenue SW 1980
Westfield 1810 11 Avenue SW 1982
Westmount Place 1100 8 Avenue SW 1979
Westport 1735 11 Avenue SW 1982

The Costs of Post Tension Cable Failure

The costs associated with post tension cable failure are substantial. In the event of a structural collapse, the implications include the loss of property and, more critically, potential loss of life. Even without a collapse, repair costs for interior and structural damages are significant, often necessitating temporary relocation of residents.

Example of residential post tension cable failure in a detached home (rarely done in Calgary) 

Can Post Tension Cables Break?

The question of whether post tension cables can break is similar to asking if the sturdiest trees in Calgary's forests can fall… it's possible, but not without significant force or neglect! 

In the realm of construction, post tension cables are designed for longevity and are incredibly robust. However, they are not invulnerable. The primary culprits when a cable fails are corrosion, excessive stress, and accidental damage during construction or renovations.

In Calgary's varied climate, protecting these cables from corrosion is paramount. The greased strands and protective sheath are the first line of defense. But, should moisture or harmful chemicals penetrate these barriers, the steel can weaken over time, leading to a risk of breakage. This is why vigilant inspection during and after construction is crucial.

While the breakage of post tension cables is rare, awareness and preventive measures are key. It is the foresight in design and meticulousness in maintenance that keep the buildings in Calgary not just standing, but thriving in the face of both human and natural challenges.

Can Post Tension Cables Be Repaired?

Encountering a damaged post tension cable in the skeleton of a building may raise concerns, but it's not the end of the story. Repairing a post tension cable is not only possible… it's a well-honed science! 

Can a post tension cable be repaired? Yes, and the repair process is a testament to the ingenuity of modern construction techniques as repairs require a specialist and a high level of technical knowledge.

Specialists first assess the extent of the damage using non-invasive techniques like electromagnetic scans. Once identified, the damaged section is carefully exposed, and the tension is relieved before any repair work begins. New strands may be added, or the damaged ones replaced, and then the tendon is re-stressed to its original tension, restoring the integrity of the structure.

These repairs are not mere patchwork though… they are precise, methodical procedures that renew the cable's strength.

With proper repair, a post tension cable can continue to support the structure as intended, ensuring that the building remains safe and stable

The Pros and Cons of Post Tension Cables vs Rebar

When constructing the foundations of any structure, the debate between using post tension cables and rebar is pivotal. Each has its place, but how do they stack up against each other?

Advantages of Post Tension Cables

  • Enhanced Strength and Stability: The tensioning process of post tension cables compresses the concrete, significantly increasing its load-bearing capacity. This means buildings can span larger distances without support columns, ideal for open-concept designs.

  • Material Efficiency: Less concrete and steel are required in post tensioned structures, which can lead to reduced costs and a lighter environmental footprint.

  • Resistance to Cracking: Compressed concrete is less likely to crack under pressure, which means a longer lifespan and fewer repairs, a significant advantage in Calgary's fluctuating temperatures.

Disadvantages of Post Tension Cables

  • Specialized Labor: The installation of post tension cables requires skilled technicians and careful coordination, potentially increasing labor costs.

  • Complex Repairs: While repairable, damaged post tension cables can be more complex and costly to fix compared to rebar.

  • Potential for Corrosion: If not properly protected or maintained, the steel cables can corrode, compromising the structural integrity.

Rebar in Construction: An Overview

Rebar, or reinforcing bar, is the traditional steel bar used to reinforce concrete. It's less complex than post tensioning and doesn't require the same level of specialized labor.

  • Installation and Maintenance: Rebar is less complex to install and maintain, but post tension cables offer greater longevity and performance, assuming proper installation and maintenance.

  • Durability: Post tension cables are generally more durable than rebar, provided they are protected from corrosion.

  • Cost: Initial costs for post tensioned slabs may be higher, but the extended lifespan and reduced need for repairs can offset this over time.

In the end, the choice between post tension cables and rebar boils down to the specific requirements of the project and the priorities of the developer. In Calgary's competitive real estate market, making an informed decision on this matter is crucial to the success of any construction venture.

Post-Tension Cables: A Glimpse into Calgary's Architectural Past

The post-tension cable construction technique made its mark during the 1970s and 1980s in Calgary, primarily influencing the city's high-rise, concrete-constructed condominiums. This method involves encasing steel cables within plastic tubing, which are then stretched to create high tension within concrete slabs, thereby enhancing their strength across larger distances.

While this construction style is predominantly seen in concrete condominiums, there are sightings of its use in parkades for certain townhomes and wood frame buildings. 

Potential Risks of Post Tension Cables

One critical aspect to consider regarding post-tension cables (PTC) in construction is the cautious approach adopted by some lenders and mortgage insurers. This hesitation often arises from concerns about the potential for corrosion and other related issues that PTC may encounter. Especially notable is the reaction of these cables to exposure to water and oxygen, which can accelerate deterioration and lead to expensive repairs.

When considering construction methods, it's imperative to factor in the ongoing maintenance expenses and the risk of cable corrosion. These challenges can translate into significant repair costs over time. As a result, some financial institutions and mortgage insurers exercise caution or limit their coverage for buildings utilizing post-tension cables. For instance, Genworth Insurance typically excludes buildings with post-tensioning from their coverage plans. On the other hand, Canada Guaranty may consider buildings erected after 2001. The Canadian Mortgage Housing Corporation (CMHC), in contrast, offers mortgage insurance exclusively for buildings constructed between 1970 and 1985 that incorporate this technology.

This cautious stance by financial and insurance institutions underscores the importance of thoroughly assessing the long-term implications of using post-tension cables in construction projects.

PTC Failures

Failures, including plumbing, HVAC, patios, envelope membranes, and roofs. These repairs can be equally expensive and may require additional funding from owners. cable tension

If you decide to consider buildings with post-tension concrete, it is crucial to confirm your options and policies with your mortgage broker or bank. Additionally, the following resources can assist you in making an informed decision:

  1. Post-Tension Cable Report: Obtain an engineer's feedback on the overall condition, potential concerns, and funding requirements for future repairs.
  2. Audited Financial Statements, Operating Budget, and Reserve Fund Study: Review these documents for details on repairs, maintenance, and funding. The reserve fund study involves a physical inspection of the building's depreciable property every five years.
  3. Board and AGM Minutes: Check for any related comments or discussions regarding post-tension concrete.
  4. Condo Document Review: Read all relevant documents yourself and consider engaging a condo document specialist for an objective summary of the building's financial health, bylaws, management, and other important factors.

Westmount Place Case Study Review

In 2010, a comprehensive review of the post-tension system at Westmount Place, a 28-story building in Calgary, was conducted by Manitcore Engineering. This evaluation included the inspection of 219 cables to assess their condition. The findings were concerning; 98% of the cables showed signs of stress, and some evidence of corrosion was detected. Based on these observations, experts recommended biennial reviews and ongoing monitoring to ensure the building's structural integrity. This case highlights the importance of regular inspection and maintenance of post-tension cable systems, especially in high-rise constructions. 

Understanding Post-Tension Cable Inspections

Regular inspections of post-tension cables are vital for ensuring the safety and longevity of structures. These inspections typically involve visual assessments, electromagnetic induction methods, and sometimes destructive testing. The process aims to detect corrosion, strand breaks, and other signs of deterioration. As shown in the Westmount Place case, timely inspections can preemptively identify issues that might compromise structural safety.

Importance of Regular Post-Tension Cable Inspections

Regular inspections of post-tension cables are a crucial aspect of maintaining the structural integrity and safety of buildings. These cables, hidden within the concrete, play a vital role in supporting large structures, but they are not immune to issues such as corrosion or wear and tear.

Inspection Techniques and Objectives

Inspection methods for post-tension cables include visual assessments, electromagnetic testing, and sometimes more invasive methods. The goal is to identify any signs of damage or deterioration early on. This proactive approach helps in preventing potential failures and extends the lifespan of the structure.

Structural Safety: Regular inspections are critical for identifying potential hazards that could compromise the structural integrity of buildings. In environments like Calgary, where varying weather conditions can impact building materials, these inspections are even more crucial.

Preventive Maintenance: Inspections help in detecting early signs of wear and tear, allowing for timely maintenance or repairs. This proactive approach can prevent more significant, costly damages in the long run.

Post Tension cable Inspection Methods

  • Visual Assessments: The first step usually involves a thorough visual examination. Inspectors look for visible signs of damage like cracks, leaks, or rusting on exposed parts of the cable.
  • Electromagnetic Induction Methods: Advanced non-destructive techniques, such as electromagnetic induction, are employed to detect internal flaws or corrosion without damaging the cables. This method is effective in identifying issues hidden from plain sight.
  • Destructive Testing: In some cases, a segment of the cable may be removed for laboratory analysis. This is usually the last resort when other methods suggest severe internal damage.

Detecting and Addressing Issues

  • Corrosion Detection: A key focus is detecting corrosion, which can significantly weaken the cables. Causes of corrosion can include water infiltration, chemical exposure, or inadequate initial protection.
  • Strand Breaks: Inspectors also look for breaks in the cable strands, which can occur due to over-tensioning, physical damage, or corrosion.
  • Deterioration Signs: Other deterioration signs include deformed sheathing, anchor head displacement, or grout defects.

Detecting Hidden Flaws

Since post-tension cables are encased in concrete, detecting issues like corrosion or strand breaks requires specialized techniques. Inspectors often use non-destructive methods to evaluate the condition of the cables without compromising the structure’s integrity.

Regular inspection of post-tension cables is not just a regulatory requirement; it's a vital practice to ensure the safety and longevity of modern constructions. Through these inspections, potential issues can be identified and addressed promptly, safeguarding the structure and its occupants.

yyc condo skyline

The Evolution of Post-Tensioning in Construction

Post-tensioning technology has evolved significantly since its inception. Initially used in bridge construction, it has become a mainstay in modern high-rise buildings. This evolution is marked by advancements in materials, tensioning techniques, and safety standards. Today's post-tensioning systems are more reliable and efficient, reflecting decades of engineering advancements and lessons learned from past constructions.

Lending Policies for Properties with Post-Tension Cables: A Comprehensive Overview

Understanding the lending landscape is crucial when dealing with properties that incorporate post-tension cables. Each financial institution has specific policies, primarily focusing on owner-occupied and insured properties. Here's a snapshot of the current stance of various lenders courtesy of our friends at Spire Mortgage

  • ATB: Financing is available for owner-occupied, insured properties only.
  • Manulife: Similar to ATB, they cater to owner-occupied, insured properties.
  • Scotia: Initially focused on owner-occupied, insured properties, Scotia has expanded its services to include both owner-occupied and rental properties, offering insured and conventional lending options.
  • Servus: Open to financing both owner-occupied and rental properties, offering options for insured and conventional loans.
  • TD: Provides financing for owner-occupied properties with less than 20% down payment, requiring insurance.
  • Strive: Their approach is more tailored, evaluating insured and insurable cases on an individual basis. This includes properties valued at less than $1 million with a 25-year amortization period.

All these lenders typically request comprehensive documentation, including condo documents and the latest engineering reports confirming the absence of major repairs. Most lenders prefer to extend loans for these properties only if they are insured. This means that even clients with a 20% or higher down payment are encouraged to pay the default mortgage insurance premium, which can be added even with a substantial down payment.

Navigating Post-Tension Cables in Pre-2000 Condominiums & Conclusion

If you're considering condos built before September 1, 2000, be aware they might not have certificates for post-tension cables use, a modern construction standard. However, this information can be obtained from the condominium corporation. It's advisable to ask about any past cable issues and the steps taken to address them, ensuring you're fully informed about the building's structural integrity.

The use of post-tension cables in construction has transformed the way buildings and structures are designed and built, particularly in urban landscapes like Calgary. These cables provide enhanced strength, efficiency, and flexibility, allowing for more innovative and expansive architectural designs. However, with these benefits come responsibilities and challenges, such as the need for specialized installation, potential risks of cable failure, and the complexity of repairs. Regular and thorough inspections are paramount to maintain the integrity and safety of structures utilizing post-tension cables.

Understanding the intricate details of post-tension cables, from installation to maintenance and repair, is essential for anyone involved in construction or real estate. This knowledge is not only crucial for ensuring the structural safety of buildings but also plays a significant role in real estate decisions, impacting everything from property value to insurance and lending practices. The evolution of post-tensioning technology reflects ongoing advancements in construction methods, highlighting a commitment to innovation, safety, and sustainability in the building industry.

Posted by Cody Tritter on
Email Send a link to post via Email

Leave A Comment

Please note that your email address is kept private upon posting.