Various roof failures, including asphalt shingle blow-off, and premature curling and cracking, has led homeowners to look for more reliable and durable solutions. As such, people often start asking about metal roofing.
Metal roofing continues to be more and more popular, despite its initial cost, because people are getting tired of having roofs that fail much before their warranties expire. The metal product offerings come in a dizzying variety of materials, appearances, textures, colours, and performance. How does one wade through all the sales claims and marketing hype to decide which options are truly the best for you? It helps to remember that there is no product invented by humans that is truly perfect in every circumstance. So the exercise is to find the product whose weaknesses are minimized in your particular circumstances, and whose strong points are fully delivered. It should not be a surprise that proper preparation and installation play a very big role in the final quality of the result. So let’s examine a selection of products and discuss how their weak (and strong) points should be considered in your selection process.
During the month of January, I’ve been called to diagnose roof leaks on an almost daily basis. These leaks have a common characteristic – they show up when it’s cold. That usually signals that there is some form of accumulation of water on the roof, usually behind an ice dam, and that the waterproofing is insufficient to stop the water from forcing its way it. The existence of an ice-dam almost always means that there is excessive transfer of heat to the roof which melts the snow on the upper sections, and the resulting meltwater refreezes on the lower section over the soffits. To reduce this heat transfer, we rely on insulation (to reduce the amount of heat leaking into the attic) and ventilation (to dissipate the residual heat before it melts the snow on the roof). However, there is another player in this game, and it can cancel out the efforts at insulating and ventilating. That player is air leakage.
Frost can be beautiful. One of the benefits of poorly insulated windows, at least for small children, is the beautiful lace shapes that form – so delicate and yet so enchanting.
Despite this beauty, there are plenty of places where in a home you do NOT want to see frost forming. Certainly, when found on windows, it is a clear sign that the window is not very good at insulating. Another place where you don’t want to see frost, is inside your attic.
Condensation plays the same role in “modern” roofing practice as “bad spirits” did in medieval times. If something went wrong, you blamed the bad spirits. Nowadays, if a roofing system is not working, it’s due to “condensation”. So let’s get into it and understand what condensation is, when can it appear in a roof system, and what corrective action you can and should take if condensation is really the cause of an apparent leakage.
If you listen to some people, you’d think that “condensation” is the satanic miasma that descends upon the undeserving, punishing them for sins committed in prior lives (or capriciously, for no reason whatsoever). In the field of roofing, roofers will look upon an afflicted home and suggest various remedies, many of which are no better than burning chicken entrails under a full moon, or uttering incantations banishing the spirits from the crevices in which they took refuge. It is also quite common for all kinds of building mischief to be blamed on “Condensation” hence informing the suitably-impressed home-owner that they are in the presence of a superior intelligence.