As many condominiums built in the late 1980s near or surpass their 30th birthday, managers are facing issues related to failing roof slabs and garage membranes. Forecasting for repairs or replacements is usually included in the corporation’s reserve fund study, but that is only the first step toward a solid strategy that will streamline costs and minimize physical disruption.
Traditionally, dealing with leaks in an underground garage meant considering a plan for complete membrane replacement. Unfortunately, such work would involve removing everything above the membrane which, in all cases, would require the removal of landscape elements such as asphalt paving, concrete walkways, retaining walls, and all trees and shrubs. This can be a traumatic process for residents; one day they are looking out to a leafy courtyard filled with wildlife, decades-old trees, and dappled shade, and the next they’re staring into an empty and lifeless space. Moreover, any semblance of the existing hardscape might be lost due to the usable space being cordoned off for construction.
Preserving landscapes
More up-to-date methods of underground garage repair exist that can result in fewer disruptions and lower costs. For example, condo property owners/managers might consider hiring a membrane consultant who specializes in technology related to repair of the expansion joints of the original garage slab rather than the entire slab and membrane. They may also benefit from working with a consultant team that includes a landscape architect to develop short and long-term repair strategies over a 10- to 15-year period. This approach could see the preservation of existing landscape areas and an extended period of enjoyment before demolition is required.
And then, in some cases, it’s better to eliminate certain species of trees and landscapes that have been ill-maintained sooner than later. In the case of trees like Acer platanoides (Norway Maple), the root systems are notoriously bad for garage roof membranes and the garage slabs as well. Dealing with these fast-growing trees early into the process can pay off in the long run.
A master plan
When planning a concrete repair, it’s worthwhile to consider developing a long-range master landscape plan that includes replacement trees with root systems that will have less impact on the roof or garage slabs over time, as well as those which grow at a sensible rate, are sturdier in nature, and have higher aesthetic value for residents. Popular suggestions include Cercidiphyllum japonicum (Katsura tree), Quercus palustris (Pin Oak), and Pyrus calleryana (Callery pear).
Advanced planning to use hard surface treatments such as permeable concrete unit pavers are a sensible alternative to poured in-place concrete or asphalt. Unit pavers are manufactured to a very strong comprehensive strength which makes them easily removed, stacked, and re-installed, and they can last for decades. Permeable versions of these pavers are also a plus where surface runoff can be dealt with in part through vertical percolation of rainwater, rather than overwhelming catch basin and storm sewers during the new norm of torrential downpours.
Having a master plan is also the first step towards developing a set of working drawings that can be put out to tender. This can be done informally and in such a way that actual costs can be assembled for short and long budgeting. Reserve fund analysis can only go so far in assembling such budgets as the math used to arrive at line items in the Study are usually formulaic and subject to great variances.
Lastly, employing new membrane and roof slab waterproofing and drainage techniques will create new structures that will have a 30- to 40-year lifespan.
Preserving the view
Significant property repairs don’t always have to come at the cost of a nice view. Putting some forethought into the repairs and considering alternate approaches can ensure long-term value for your landscape and, in turn, your asset.
Kent Ford is founder and principal of Kent Ford Design Group Inc., a Toronto-based landscape design and project management firm (www.kentforddesign.com)
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