By Alfred H Y Lam, BASc in Civil Engineering, IIT, CRP
Senior Depreciation Report Planner
Click here to read Determining the Age of the Exterior Cladding and the Windows in Multi-Resident Buildings in its entirety
While doing depreciation reports, reserve fund studies or building condition assessments, we often get asked how we can determine the age of a building component by looking at it. Although not without aberrations, there are some tell-tale signs that indicate the age and the remaining life of features such as windows, claddings and veneers, roofs and fencing. Architectural styles and innovations in manufacturing will also have an influence on how long certain components may last. We have written a series of articles explaining what signs we look for to determine age and remaining lifespan for our depreciation reports, reserve fund studies, or building condition assessments. The first article of this series talks about determining the age of the exterior cladding and the windows in Strata and Condo Corporations.
The exterior cladding and the windows are, in almost all cases, two of the most expensive components of a building. While they are long-lasting (typically in the range of 25-40 years), there are many factors that may increase their apparent age, and in turn, reduce their remaining useful life. These factors may include general wear-and-tear as well as the quality of workmanship of the original installation.
The most common materials for exterior cladding in a strata building include: stucco, wood, fiber-cement, vinyl, and brick/stone veneer. With the exception of vinyl and brick/stone veneer, the other materials generally require paint coating to provide an additional layer of protection against the elements. While re-painting projects can serve to preserve the condition and maintain the longevity of the cladding system, this cannot be expected to remedy pre-existing deficiencies. The presence of any deficiencies will negatively affect the observed conditions such as:
- Cracks – If left unattended, cracks may expand over time through water entry and freeze-thaw cycles. Any water ingress is likely to deteriorate components behind the surface layer.
- Stains – While lighter-coloured surface stains can usually be remedied through cleaning, darker stains may be an indication of sustained concealed damage. Such damage is normally caused by water penetration, and if left unattended, will often lead to mold.
- Peeling/Chipping Paint Coat – Peeling and chipping may be due to varying factors. If the paint coat is relatively new, the surface may not have been properly prepared. A new paint coat is typically applied to a cleaned surface after a combination of sanding, scraping, and chiseling in addition to the application of a suitable primer. If the paint coat is fairly old, the cause of paint loss is likely a matter of weathering. It is generally recommended that vinyl siding not be painted, primarily because vinyl expands and contracts quite significantly according to temperature changes. As a result, many paint products do not adequately bond to the vinyl material. Moreover, vinyl typically comes in solid colours and is generally not affected if it happens to be scratched. However, the heat sensitivity of vinyl siding is a major drawback. As a result, it is susceptible to warping, particularly where there is constant sun exposure. In addition, warping may also occur if a barbecue is used too close to the vinyl siding.
Brick/stone veneers can generally last the life of a building but the mortar joints used to bond these materials does not last as long. Deficiencies, typically in the form of cracks in the mortar joints, will develop over time and must be repaired to keep the cladding system safe and intact. If cracks are not attended to in a timely manner they will often cause veneers to detach from the subsurface. In some instances, the scratch coat may not have been prepared sufficiently during original installation, resulting in inadequate adhesion between a veneer and the substrate material. Deficiencies in a localized area are often indicative of the level of wear or sub-par workmanship of a larger wall region, which will have a negative impact on the observed age of the cladding system.
The observed age of windows generally depends on several factors including the frame material, the flashing details, and the architectural style.
Window frames are typically made from wood, aluminum, or vinyl. Among these, the upkeep of wooden window frames is the most demanding and is not generally achieved in strata buildings. As a result, many wooden frames observed are in poor condition, often containing some form of rot and decay. Aluminum window frames are not likely to decay but they do deteriorate. Specifically, early aluminum windows consist of uncoated natural aluminum which is subject to pitting and corrosion. In addition, putty was used to hold the glass in these aluminum frames. Over time, putty hardens and pieces fall out causing a loss of air tightness and loose glass panes. With the advance in technology, modern aluminum windows, vinyl windows, and hybrid windows are free from many such issues and are generally low-maintenance. The edge seals of modern windows are good but they are not perfect. Failure of the seal often results in fogging of insulating glass units (IGU). While one or two window seal failures in a large complex can be viewed as localized events and not reflective of the overall condition, a considerable percentage of failures may be considered as a systemic issue that negatively affects the observed age.
With wind-driven rain, wall surfaces and windows will get wet throughout the course of their lifespan. As a result, the observed condition will be largely dependent on how well the system was designed and installed. Water resistance is particularly important to the interface between the window frame and the wall. Head flashings are installed above windows to help keep water away from this vulnerable area. However, to be effective, flashings must extend past the sides of windows and must slope downward and outward away from the wall surface. Unfortunately, flashing is often missing in older buildings that have yet to replace or retrofit their windows. Sometimes in newer construction, building settlement (often in the first few years) or physical damage (due to excessive pressure from power washing) can cause deformation and warping of the head flashing which sometimes slopes back towards the building, directing water to the window frame rather than away from it, as intended.