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.
Metal roofs with smooth surfaces (native metal like copper or zinc, or painted metal) are generally quite slippery when wet. In winter, under the right conditions, this allows accumulated snow (and ice) to avalanche off roofs. If the fall area has no traffic or things that can get damaged, that’s probably a good thing, as there is less weight on the roof. If the snow ends up hitting people (your kids, your postman/woman, your visiting friends), or sensitive property (your car, your expensive BBQ, your heat pump, your eavestroughs/gutters), then that’s not a good thing. Unfortunately, if the snow control methods were not part of the original roof design and installation, then intervening after the roof is installed is often an area ripe with unintended consequences.
Metal roofs are much better products compared to asphalt shingles when considering durability, performance, and resistance to the weather. However, one aspect of metal roofs that often surprise new owners is the difference in behaviour during the winter, if the metal is a smooth metal like painted steel, painted aluminum, or native copper.
Most people think they have a good grasp of how roofs work – the shingles (usually asphalt) keep the water out, and that they do that by being the waterproof layer that stops water from getting in. That’s more myth than fact.
Another myth, is that caulking is an acceptable way to achieve waterproofing.
Another myth, is that if you have ice-and-water shield on your roof, you’re good.
What all these myths have in common is that they misunderstand how a sloped roof system works in reality.
Whether we believe that human activity has caused or contributed to climate change, the simple reality is that the weather is not the same as it was before. The warming of the atmosphere promotes more evaporation, and this brings an increase in the energy contained in the atmosphere. More energy means more variation, with larger movements of air, stronger atmospheric pressure variation (both highs and lows), heavier precipitation, and much more wind.
In practical terms, this means that winds of 80+ km/hr will be more common, and we should expect at least several times a year when our roofs will see winds of 120+ km/hr. In terms of precipitation, heavy downpours of 30-40mm per hour may be more common, and need to be planned for. We can also expect heavier snowfalls, and rapid changes in temperature.
So… how is your roof set up to handle these weather conditions? Probably not all that well. If your roof was put together to meet the minimums in the building code, which was based on data accumulated prior to the 1980’s, then your roof is built to deal with conditions that have dramatically changed since that time.
The typical roof failure we’ve seen in recent years include:
Water infiltration due to wind-driven rain
Damage to fascia, soffits and siding
Leakage due to rapid melting of snow accumulating on the roof, then refreezing,
Leakage due to volume of rain overwhelming the gutters, and backing up the eaves, valleys and end-walls,
Excessive wear on shingles from water falling from a higher level
Excessive drying-out due to prolonged heat and sun exposure
Caulking failures around chimneys, skylights, vents and other roof features
Excessive snowfalls with up to 24″ or more of snow accumulation requiring snow clearing to reduce the weight on the roof.
It would be a good idea to verify that your roof system can cope with the new conditions, and if weaknesses are found, to determine the best way to “fortify” your castle. If you wait for a news-worthy weather event to damage your roof, you may be looking at a very expensive repair bill, not to mention inconvenience and even some personal danger.
If you haven’t considered it before, maybe it is time to look at some of the newer products and installation methods that have a much better ability to cope with the temper tantrums that Nature seems to throw more often.
At the very least, you may want to look at the incorporating layers of protection that should allow your roof to withstand the more extreme events. Each roof behaves somewhat differently, so an inspection is usually needed to establish the potential weaknesses, and the appropriate counter-measures.
No, it’s not too late. In some ways, winter is the perfect time to get an understanding of how your roof is working. Heat loss through the roof, unequal ventilation, and similar problems are easy to detect with the roof covered (fully or partly) by snow. The cold temperatures also help in detecting condensation and leakage issues in the attic.
Certainly, once the cold weather arrives, it is too late to do asphalt roofing, as that type of product needs the heat of the sun to properly “seal”. However, metal roofing can be installed year-round, providing proper precautions are taken to protect both the roof and the workers.
If you’re thinking of changing your roof in spring, this is a good time to start doing the research. Not sure about what SHOULD be considered? Give me a call and we can arrange an interview. I will listen and try to understand your needs and priorities, look to see what the actual situation is, and then propose some options.