Siding is the renovation most homeowners think about least and pay for most. It covers more surface area than any other part of the house, it is the first thing a buyer or a guest sees, and when it is done badly the damage hides behind the wall for years before it shows up as a rotten window frame or a mould problem. Few places make this clearer than Calgary, Alberta, a city that sits in the middle of Canada’s hail corridor, swings 40 degrees between seasons, and tests exterior walls harder than almost anywhere in North America. Hamilton Exterior Renovations, a contractor that handles the siding Calgary homeowners replace after every major storm, has stripped enough failed walls to know that the same eight mistakes show up again and again, in every climate, on every budget. Here they are, with what to do instead.
Mistake 1: Buying the thinnest vinyl the store sells
Vinyl siding is sold by thickness, and the difference between a panel at 0.040 inches and one at 0.044 or 0.046 inches does not look like much on the shelf. On the wall it is the difference between a product that cracks in the first serious hailstorm and one that shrugs it off. Thin builder-grade vinyl also goes brittle in deep cold, fades faster on sunny elevations and shows every wave in the sheathing beneath it.
In Calgary, where the hailstorm of August 2024 caused an estimated C$2.8 billion in insured damage, thin vinyl is the material most often being removed. The fix is simple: specify premium-grade vinyl with a fade-resistant cap layer, or step up to insulated vinyl, which laminates a rigid foam backer to each panel. The foam stiffens the panel against impact, lies it flat against the wall, and adds a modest layer of insulation. It costs a few dollars more per square foot and routinely outlasts the thin product by a decade.
Mistake 2: Choosing the material for the brochure, not the climate
Every siding product performs well somewhere. The mistake is assuming it performs well everywhere. Vinyl is excellent in moderate climates and vulnerable in hail and extreme cold. Traditional stucco handles sun and impact but traps moisture in freeze-thaw conditions. Wood looks beautiful and demands maintenance under intense UV. Fibre cement handles impact, fire, cold and sun, but depends on precise installation.
Calgary’s climate forces the issue because it delivers all four loads at once: golf-ball hail in summer, Chinook winds that lift winter temperatures by 20°C in an afternoon and drop them back overnight, more than 330 days of high-altitude sunshine, and overnight lows near -30°C. That is why fibre cement, principally James Hardie’s freeze-thaw formulation, has become the default specification in the city when the budget allows, and why insulated vinyl is the usual choice when it does not. Homeowners elsewhere should run the same exercise: list the two or three harshest things your weather does to a wall, and choose the material that handles those, not the one with the nicest photo.
Mistake 3: Letting the installer side over the old siding
Installing new siding directly over old is faster, cheaper and tempting, and some contractors will offer it as a cost saving. It is also the most reliable way to seal rot, trapped moisture and failed sheathing behind a brand-new wall where nobody will see it for twenty years.
A proper re-side strips the wall to the sheathing, inspects it, and replaces anything soft or stained before a single new panel goes on. On a house old enough to need new siding, the crew usually finds something, most often around windows and at the base of the wall. Finding it now costs a few hundred dollars in sheathing. Finding it in a decade costs a wall.
Mistake 4: Reusing the old house wrap and flashing
The parts of a siding job that keep water out are the parts nobody sees: the water-resistive barrier across the whole wall, the membrane around every window and door, the metal flashing above each opening, and the small kick-out flashing where a roof meets a wall. These components are inexpensive, and on an older home they are almost always worn out, torn, or were never installed correctly in the first place.
A quote that does not include new house wrap and new flashing on every opening is not a complete quote, no matter how good the price looks. Contractors in freeze-thaw climates learned this expensively, because a wall that lets water in and then freezes it comes apart from the inside. The rule holds everywhere: new siding, new barrier, new flashing, every time.
Mistake 5: Running the siding to the ground
Siding that touches grade, a deck, a patio or a roof surface sits in water every time it rains or snow melts. In cold climates that water freezes against the bottom edge of the panel all winter. In warm climates it wicks up into the material and feeds mould and rot. Either way, the lowest 150 millimetres of the wall is where the damage starts.
Manufacturers specify minimum clearances for exactly this reason. James Hardie, for instance, calls for 150 mm between the cladding and finished grade, and a gap above roofing and hard surfaces. A good installer measures these; a careless one runs the panel to the ground because it looks tidy. Check the clearances yourself when the job is done. It takes a tape measure and two minutes.
Mistake 6: Nailing vinyl tight
Vinyl expands and contracts with temperature, by as much as a centimetre on a long run between a cold night and a hot afternoon. It is designed to hang loosely on its fasteners so it can slide. An installer who drives the nails tight, or who does not leave the specified gap at the ends of each panel, produces a wall that buckles and ripples in summer heat and pulls apart in winter cold.
This is a skill issue, not a product issue, and it is the most common reason a vinyl job looks wrong within a year. If your siding is vinyl, ask the contractor directly how they fasten it for movement. The right answer involves nail heads left slightly proud of the hem and expansion gaps at every joint. If they do not know what you are talking about, keep looking.
Mistake 7: Picking the colour before the material
Dark, moody exteriors are in style, and for good reason. Charcoal, deep green and near-black look striking, especially against snow or a bright garden. The mistake is choosing the colour first and the material second. Dark vinyl absorbs more heat than light vinyl, which means more thermal movement, faster fade on south- and west-facing walls, and in some cases panel distortion. Fibre cement and factory-finished engineered products hold dark colours for years without that trade-off.
If the heart is set on a dark house, the honest sequence is: decide what material the climate and budget allow, then choose the darkest colour that material carries well. On vinyl, that may mean a mid-tone body with the deepest colour reserved for trim, shutters and the front door, where it does the most visual work anyway. On fibre cement, go as dark as you like.
Mistake 8: Hiring on price alone
Siding quotes vary enormously for the same house, and the lowest one is rarely the cheapest over the life of the wall. The price gap is usually explained by what has been left out: the strip-down, the new barrier, the flashing, the clearances, the proper fastening, the written workmanship warranty. Each of those is invisible on the day the job is finished and expensive when it is missing.
A trustworthy contractor will itemise the quote (materials, labour, removal, disposal, repairs), explain what happens if rotten sheathing turns up behind the old siding, and put a multi-year workmanship warranty in writing on top of the manufacturer’s product warranty. Hamilton Exterior Renovations, for example, backs every installation with a ten-year workmanship warranty and has the owner personally assess and inspect each project. That is a reasonable benchmark to hold any contractor to, in any city.
What a siding project should actually cost
Numbers vary by region, but the Calgary market in 2026 gives a useful reference. Premium vinyl installs at roughly C9 per square foot of wall, insulated vinyl at C
11.50, and James Hardie fibre cement at C
16, all including removal, barrier, flashing and standard trim. For a typical two-storey home that works out to about C
22,000 in vinyl and C
38,000 in fibre cement. Stucco removal, sheathing repairs and new soffit and fascia add to that.
Two things move the number more than most homeowners expect. Contractors price by wall area, not floor area, so a tall two-storey with lots of corners carries far more siding than a bungalow with the same floor plan. And in hail-prone regions, storm damage to one or two elevations can sometimes be handled as an insurance-funded partial replacement, which is worth exploring before committing to a full re-side.
The short version
Choose the material for the weather, not the catalogue. Strip the old siding and inspect the wall. Insist on new wrap and flashing at every opening. Keep the cladding off the ground. Fasten for movement. Pick the material before the colour. And hire the contractor who itemises the quote and warranties the work, not the one who simply undercut everyone else.
Homeowners in Calgary learn these rules one hailstorm at a time. Everyone else can learn them for free, and spend the savings on the front door.
