A package looks like it removes the decisions
Canadian properties get their entrances built in late summer while the ground is still workable. A wrought iron fence bought as a package with the gate arrives with everything matched, which is genuinely useful and quietly shifts the difficulty somewhere else.
The gate is one object and a wrought iron fence is many. Matching them visually is solved in the catalog, while making them meet in a straight, level, continuous line across real ground is solved on site by whoever is digging the holes.
Panels come in fixed lengths, and the ground does not
The panels of a wrought iron fence are welded units of a set length, usually somewhere between six and eight feet. Every post has to land exactly one panel apart, which means the layout is decided by arithmetic before anything is dug rather than by where a post would be convenient.
This is what makes the question of how far apart to set fence posts different here than for a wire or board fence. There is no adjusting a panel to suit a spacing, so the spacing is fixed and the leftover distance shows up as one short bay at the end.
Deciding where that short bay goes is a design choice
A run of 110 linear feet of wrought iron fence rarely divides evenly into whole panels. Putting the odd bay at a corner, behind a shrub, or against the house hides it, while leaving it beside the gate puts the one visibly different section where every visitor looks.
A wrought iron fence on sloped ground cannot follow the slope
Panels are rigid rectangles with welded pickets, so they cannot be racked to match a grade the way a panel with pivoting connections can. On sloping ground each one stays level and steps down from its neighbor, which produces a staircase along the run.
Those steps leave triangular gaps under the low end of each panel. On a gentle grade that is a few inches and nobody minds, while on a steeper slope it becomes large enough that dogs get out and the gap has to be closed with masonry or fill.
The gate posts belong to a different job than the fence posts
Line posts hold a panel that carries no weight beyond its own. Gate posts carry a swinging leaf that puts a constantly changing load on them, and on a bi-parting entrance there are two of them that must stay in the same plane for the leaves to meet.
Hinge adjustment is what keeps that alignment usable. Hinges with some adjustment built into them let a leaf be brought back into line after the first winter, while fixed hinges leave resetting the post as the only option.
That is why gate posts go deeper and get concreted more generously. Frost movement that would tilt a line post by a degree and go unnoticed will put a pair of gate leaves visibly out of alignment by the second Canadian spring.
A bi-parting gate needs somewhere to latch in the middle
Two leaves meeting in mid air have nothing to fasten to unless something is put there. A drop rod into a socket set in the driveway holds the first leaf still so the second has something solid to close against, and without it both leaves move whenever the wind does.
That socket has to be set at the same time as the posts. Cutting into finished asphalt afterward is possible and untidy, and being an inch out means the rod no longer drops cleanly into it.
Corner and end posts take load the line posts never see
A straight run pushes on its posts from two directions that mostly cancel. At a corner those forces add rather than cancel, and at the end of a run there is nothing pulling back at all, so both need more depth and more concrete than the posts between them.
Where plowed snow ends up belongs in the same conversation. A bank pushed against ornamental panels all winter puts a steady sideways load on posts sized for wind, and the panels nearest the driveway lean first.
Set the whole line before concreting any of it
String lines and dry fitting panels before mixing anything is what catches an accumulated error. A quarter inch gained at each of fifteen posts is nearly four inches by the end, which is enough that the last panel does not fit and one hole has to be dug again.
Rock is the reason a fence line moves
Canadian ground turns up boulders at inconvenient depths, and a hole that hits one leaves a choice between breaking through and shifting the layout. Because panel length fixes the spacing, moving one post moves every post after it.
Probing the line before digging avoids that. An hour with a bar along the marked positions finds most obstructions, and a layout adjusted on paper costs nothing compared with one adjusted after eight holes are concreted.
Frost depth decides how deep the holes go
Footings that stop above the frost line get lifted every winter and settle unevenly every spring. Across most of Canada that means holes considerably deeper than the ones a fence contractor in a mild climate would dig, and the gate posts deeper still.
Decide about a gate opener before the driveway is finished
Automating a wrought iron fence entrance later means getting power to both gate posts, and the cheapest moment to run a conduit under a driveway is before there is a driveway over it. Owners who skip that step usually end up with a surface mounted cable or a trench through new asphalt.
Fence systems divide by how they meet the ground
•Welded panels: rigid, must be stepped on slopes
•Rackable panels: pivot to follow a grade
•Site built pickets: follow anything, slowest to build
Where a matched package helps and where it does not
•Strength: gate and run share one appearance
•Strength: quantities arrive already worked out
•Limit: panel length dictates every post position
•Limit: sloping ground produces gaps to close
Weighed against building a run to measure, a package costs flexibility in the layout and returns an entrance that looks designed rather than assembled. A landowner near Peterborough laid his out on paper first and moved the odd bay to the tree line, where nobody has noticed it since.
Entrances are being laid out before the driveway is poured
Property owners increasingly set out the approach, the gate, and the run as one element completed at the same time as the driveway, rather than adding a gate years later to a fence that was never laid out to accept one.
That way of planning an entrance is why the fencing TMG Industrial supplies is offered as matched runs and gates rather than as components a buyer has to reconcile on site.