Why does concrete crack?
Unlocking the mysteries of a critical building resource
Concrete has been the main stay of building construction for generations. Today, traditional reinforced concrete is an integral and important component of building structures. It usually takes the form of footings in ground, slabs on ground, columns and suspended slabs.
Concrete however, is not the perfect substance. As such it can suffer from defects. These defects can have a huge impact on the appearance, capital expenditure, maintenance costs, safety and effective life of the total structure.
What then are the typical forms of concrete defects? Some of the more common defects can be categorised as follows:-
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Structural design inadequacies – distortion, bending cracks, deflection, shear cracks, impact damage temperature change cracks, abrasion, torsion cracks and erosion.
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Environmental causes – weathering/staining, biological growth, bacteriological attack, efflorescence (lime leaching), freeze-thaw damage and fire damage
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Aggregate properties – aggregate swelling/shrinkage/softening, alkali-silica reaction and sulphide staining/spalling.
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Chemical attack – sulphates, chlorides, acids and salt weathering.
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Reinforcement corrosion – cracking, spalling and de-lamination
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Concrete Cancer – cracking of the concrete caused by the corrosion of steel reinforcement in concrete structures
The shattering truth about glass
Since the 1960s, there have been numerous, high profile incidents of ‘spontaneous” failure of toughened glass in building facades. In some cases, glass has been known to simply ‘pop’ out of high-rise building windows and fall onto the streets below Why does this happen? The cause lies within the makeup of the glass itself.
Nickel sulphide is a rare and unintended inclusion in the production of glass panels. However, the presence of nickel sulphide can be a problematic one. This is due to what is technically called, ‘delayed transformation’.
For those interested in technical detail, these follow:
Nickel sulphide crystals can take one of two forms. At high temperatures, a dense crystal is present. At lower temperatures, a less dense crystal is present. Provided the transition from high to low temperature (ie. cooling) is gradual, the crystal can move between forms without problem.
For example, in ordinary annealed glass, the crystals do not cause problems because the cooling process occurs slowly during manufacture.
Don’t let your refurbishment get you hot under the collar
When undertaking due diligence work, we often identify instances in which owners have carried out quality refurbishments that include foyers, floors and ceilings.
While this certainly does help with the building’s maintenance and appearance, the refurbishment often overlooks a critical part of the equation: the air conditioning unit.
Air conditioners are a critical resource for buildings everywhere. Why is it then that they are so often overlooked? Many building owners do not consider the air conditioning unit to be particularly important in terms of refurbishment. Some owners do not even consider that air conditioning units would ever need to be refurbished. This however, is certainly not the case.
For most buildings, the air conditioning units were installed when the building was constructed. In some cases, this is as many as thirty years ago. As such, these air conditioning systems were designed to suit conditions relevant to the times when the building was originally constructed. For older buildings, this means that the air conditioning was designed to cater for factors that we consider common today such as computers, longer working hours and work station clusters.
Why is this a problem? Computers and body temperature each affect the general air flow required within a building. Consider a 10 storey building with a central air conditioning unit. It is likely that over a period of years, the number of employees within the building would have increased; the required electricity would have significantly increased; and the hours of work would most likely also be significantly greater.
Don’t overlook the value of proactive maintenance
For many years, building owners have subscribed exclusively to the theory, if it aint broke, don’t fix it. This however can be an expensive mistake.
It is important to acknowledge that a building is an asset. As such, it needs to be protected and maintained to ensure that its value is not eroded.
To retain and attract tenants, your asset must be presented in the best possible condition, which in turn will maintain or increase its value.
Napier & Blakeley Building Consulting Manager, Nigel Towse says that if building maintenance is ignored, it can have significant consequences.
“There is a common misconception that buildings have long lives and only deteriorate gradually. This may be true for the more robust forms of structure. However even these can deteriorate rapidly with structural failure, environmental issues, chemical attack or the ingress of moisture.”
The health and well being of tenants is paramount in any leased asset and is heavily linked to how the building is maintained. There are basic, statutory obligations that require regular maintenance to be carried out to this end. In particular, cleaning, testing, and checking etc, of fire systems, boilers, lifts and hoists.
“By planning and carrying out your maintenance efficiently, you can minimise your capital expenditure. This will ensure that your asset is safe, economical, efficient, environmentally friendly, and retains its value,” says Towse.
Are your Fire Insurance Assessments up to date?
Damage to property and buildings by fire and other disasters, natural or otherwise, costs Australians hundreds of millions of dollars every year. In Australia, the most common building disaster is fire, so it is important to be prepared.
Napier & Blakeley’s fire insurance assessments are called reinstatement cost assessments. The function of these assessments is to determine the amount a property needs to be insured, to cover the possibility of damage from a disaster. This can include the demolition of the remaining component of the property followed by reconstruction.
Construction markets nationally have gone through significant upturns in cost in recent years. While the increase in these costs may have slowed, they are still far greater than they were a few years ago.
Financiers Reports – Are you getting what you really need?
Financier and developers, will often shop around to get the cheapest quote in an effort to shave a few hundred dollars off the cost of their reports. The question that remains is: Should they prioritise financial savings, or a quality level of reporting?
Developers often see financiers reports (risk assessments during the construction period of a development) as a necessary evil to get their hands on the financiers cash, so the cheaper the better. However where the drive is towards controlling of costs to maximise return, the saving in a financiers report could leave them exposed to the risk of far greater costs during the life of the project.
Paul Cosker, Manager, Quantity Surveying at Napier and Blakeley says that a well thought-out financier report will provide commentary on the project. However, in order to achieve that, the developer should sometimes be prepared to pay a little extra for a thorough review at the outset.
Interview with Roger Walker, National Head of NB Sustainability
NBNews: What is NB Sustainability?
RW: Sustainability is not only about Corporate Social Responsibility; it’s responsible financial management.
Environmental and social sustainability initiatives directly impact the productivity and financial bottom line of running and occupying a property profitably; building, buying, tenanting, selling and demolishing.
Responsible sustainability is applying the right initiative at the right time to maximise corporate and financial returns during the life cycle of a property development.
Napier & Blakeley not only have the reputation and breadth of services to deliver this technically, their knowledge of the needs of both tenants’ and landlords’ also allows them to provide valuable strategic, positioning and portfolio priority advice.
NBNews: Are there differences between Tenant and Landlord Sustainability needs?
RW: Yes. The two perspectives are not necessarily mutually exclusive, but often opportunities are lost in the tenant and landlord relationship that could be leveraged with objective mediation. You need to work with a partner that understands where the best returns for your investment exist.
Owners need advice and due diligence that delivers the best market return on their property whether it’s during demolition, construction or refurbishment of existing buildings while tenants’ needs focus on their Corporate Social Responsibility commitments and maximising day to day productivity, such as energy use, recycling and staff wellbeing.
Responsible Sustainability
“If you can keep your head when all about you are losing theirs. . . Yours is the earth and everything that’s in it…” …Rudyard Kipling
While markets across all industries are in a state of stress and chaos at the moment, it is now that the true industry leaders will prove themselves as they keep sight of the business fundamentals that underpin long term profitability. Cost management is the key focus and due diligence in all business aspects is required, not just to survive but to consolidate for the future when conditions improve. The skill is to trim the sails and stay in the race.
There are restrictions on capital funds and a degree of talk about delaying projects and cutting back on capital works programs. Environmental sustainability for some businesses has taken a back seat as recovery is worked out and debt and financing options are reviewed.
To maximise return we must continue to focus on sustainability and the opportunities to advance in this area to meet future tenant and regulatory demands. The danger of short term cost cutting is that the long term positioning of the building can be compromised as the demand for sustainable, energy efficient and star rated buildings increases.
What will you do in your summer holidays?
Summer time is a great time to take stock of your business and a great time to think about and diarise some property housekeeping issues that quite often get overlooked in the bustle of normal day to day business.
However if you consider this now, you can plan to carry out some crucial housekeeping duties in January when business is traditionally quieter.
Some of the not so sexy but absolutely essential items to consider to maximise your return and minimise your cost and risk are as follows:
Property Replacement Insurance: given the sizeable increases in construction costs in recent times, have you considered whether your properties are correctly insured? Do you know what you are insuring: base building and / or fit out?
Capital Expenditure Planning: what items have you planned over the next calendar year? How will they be managed?
Maintenance: are your maintenance contracts up to date and appropriate? Are there any routine maintenance items that can be efficiently attended to in this quiet time?
Tax and asset updates: Is your base schedule correct? Have you carried out any upgrade works during the financial year to date for which you can claim either a tax write off or a future tax deduction?
Condition Audits: Do you need to create or update any condition surveys of your tenanted properties?
Tenancy Make Good: Do you have a schedule of lease expiries that will occur during the year? Are there any “repairing and make good” obligations that need to be planned with the tenant?
N&B can assist with all of the above to help you really enjoy your summer holiday.
So where will all of this leave us in 2009 and beyond?
We are now in a Catch 22 market, which will make for an interesting year all round in property and development in Australia.
Property
There is an inordinate amount of property on the market nationally, from residential housing and apartment’s right through to large retail and commercial properties and any number of development opportunities across all sectors of the market.
The problem is credit and debt funding. Australian banks no longer have the cash funds and backing they previously had from the larger offshore investors which makes it much more difficult for them to lend causing them to adjust their lending criteria.
We are aware of a recent example where a blue chip client, with AAA rated companies and virtually no debt, was unable to secure debt finance from their banker of more than ten years to develop a commercial office building in which they would have taken more than 50% of the available space. In another development funding application of only $20m, it was suggested that the $20m be syndicated across four lenders at $5m each – unheard of in recent years.
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