Metal roofing
Metal roofing, and the slopes where it is the only answer
Nanaimo Roofers installs standing seam and profiled metal roofs across Nanaimo, Lantzville and Cedar. Profiled metal starts at a slope of 1 in 4 under Table 9.26.3.1 of the BC Building Code and carries no upper limit, which is exactly where a roof too flat for shingles and too steep for membrane lands.
Metal is usually chosen for how long it lasts. It gets specified, though, for where the slope sits.
The one slope where the table changes hands
Profiled metal begins at 1 in 4. Modified bituminous membrane ends at 1 in 4. The two coverings meet at a single slope and swap either side of it, so a roof measured at 1 in 5 is a membrane roof and one at 1 in 3.5 is a metal roof, whatever the preference was going in. Sheet metal shingles also start at 1 in 4. Asphalt cannot go below 1 in 6 under any method.
What the roof is detailed against
Appendix C of the BC Building Code lists design values by location. Nanaimo sits at 15 m elevation with a ground snow load of 2.1 kPa and a rain load of 0.4 kPa, a 1-in-50 hourly wind pressure of 0.50 kPa, a one-day rainfall of 91 mm, and a driving-rain wind pressure of 200 Pa. Those figures decide panel gauge, clip spacing and fastener pattern. A metal roof that fails on this coast usually fails at the fasteners, not the panel.
Standing seam against profiled
Standing seam hides its fasteners under the seam and lets the panel move as it heats and cools. Profiled panels fasten through the face, which costs less and puts a gasket at every fastener. Both hold up here; the difference shows up after twenty years, in how many of those gaskets are still doing their job.
What it costs and how long it lasts
Metal runs $8 to $30 a square foot installed and lasts 40 to 70 years, against $4 to $9 and 25 to 30 years for architectural asphalt. On a roof that will not be touched again for two generations that arithmetic works. On a house being sold in three years it usually does not.
Where the permit answer sits
The City of Nanaimo issues building permits under Building Bylaw 2016 No. 7224. The Regional District of Nanaimo requires a permit for new construction, alteration, addition and demolition across every electoral area. The answer gets confirmed with the authority that covers the address before the work is booked.
What's included
Standing seam metal roofing
Profiled metal roofing
Low-slope metal transitions
Snow guard installation
People also ask
Is a metal roof loud in the rain?
A metal roof over a sheathed and insulated attic is not measurably louder than asphalt. The noise people remember comes from metal fastened straight to purlins over an open barn or carport, with no deck and no insulation between.
Can metal go over an existing shingle roof?
It is possible over a single sound layer, and it is still the wrong call on most houses. Going over the top leaves the deck unseen and the eave detail unchanged, and those are the two places a roof of this age actually fails.
Does metal need different venting?
The requirement does not change with the covering. Section 9.19.1.2 sets the same 1/300 of insulated ceiling area, or 1/150 below a 1-in-6 slope, split at least 25% top and 25% bottom.
Will a metal roof shed snow onto the walkway?
A smooth panel on a steep slope sheds in sheets. Where a roof discharges over an entry, a walkway or a gas meter, snow guards go into the scope at quote stage rather than after the first winter.
Keep exploring
- What a new roof costsInstalled price by material, and what moves it on a given roof.
- Permits by communityWho issues the permit for an address, and what each authority asks for.
- Where the work isThe communities covered across the Regional District of Nanaimo.
- New roof installationFull tear-off, deck repair, underlay and architectural shingles or standing seam metal. A fixed price, with the sheathing unknowns listed separately.
- Roof repair and leak tracingFlashing, valleys, penetrations and laps. Finding where water enters a roof, which is almost never directly above the stain on the ceiling.
- Nanaimo Roofers home