SettingsSettings for this calculationUS
The total run length of curtain wall requiring anchor attachment to the structure.
Measured along the STRUCTURE the brackets attach to, which is not the same as along the facade wherever the two diverge. Returns, corners and set-backs are where anchors bunch up rather than thin out, so a plain run taken off the elevation under-counts any facade with geometry in it. Where the curtain wall passes a floor without attaching, that length still belongs to the span above or below it, not to nothing.
The maximum center-to-center spacing between anchor brackets, per the system's engineering.
A MAXIMUM, from the system engineering — so the built layout is this or closer, never further. It also has to land on something: a spacing that divides the run neatly and falls between slab edges is not a spacing, and when the structure dictates the position, the answer is a bigger bracket rather than a longer gap. Check it against where the floors actually are before ordering to it.
Anchor brackets needed
27 brackets
- Bays along the run
- 26
- Bracket centres, as fixed
- 5 ft
They open the calculator with your figures already in it
Curtain Wall Anchor Bracket Spacing Calculator: 27 brackets — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
Show calculation logicHide calculation logic
How this was calculated
Formula source(s)
- Anchor bracket count = ceil(perimeter run length ÷ bracket spacing) + 1, the standard layout method for spacing repetitive structural attachment points
Inputs used
- Total Perimeter Run Length
- 130 ft
- Anchor Bracket Spacing
- 5 ft
Intermediate steps
- Bays along the run
- 26
- Bracket centres, as fixed
- 5 ft
What this calculation does not cover
- The spacing is something you type in, not something this page checks. The same 40 m run returns 28 brackets at 1.5 m spacing and 15 brackets at 3.0 m spacing, and nothing in the arithmetic objects to either figure. Whether that spacing is adequate depends on the wind pressure acting over each bracket's tributary panel area, the dead weight hung on the bracket, and the rated capacity of the bracket and its fixing into the slab edge — none of which is calculated here.
- The result is one line of brackets along one run at one level. A curtain wall is normally tied back to the structure at every floor slab, so the building total is this figure multiplied by the number of anchorage levels: a 40 m (131 ft) perimeter over eight storeys is eight runs of 28, not 28 brackets in total.
- This counts anchor positions, not the hardware schedule. Many systems place a separate dead-load bearing bracket and a wind-load tie-back at each attachment point, and every bracket needs its own bolts, shims and packers, so the purchase list can run to two or more brackets and four or more fixings per position counted here.
- The run is divided by whatever spacing you enter, with no reconciliation against the mullion or panel grid. Brackets have to land on mullion centrelines, which means the spacing must equal the panel module or a whole multiple of it. Entering 1.5 m spacing on a 1.2 m panel module gives 28 brackets that mostly fall between mullions, where the 1.2 m module gives 35 that all land on one.
- The plus one assumes an open run with two free ends. On a perimeter that closes back on itself the final bracket is the first bracket, so the closed-loop count is one lower than shown: a 60 m (197 ft) closed perimeter at 1.5 m (5 ft) spacing returns 41 here where the loop has only 40 distinct positions.
Estimated cost — your price
This site holds no price list for this material — local prices vary too much to publish honestly. Enter your supplier's price and the result is costed with it.
Computed in your browser — nothing you enter is uploaded. Presented in US customary units and US trade terminology. Where a formula follows a published standard, that standard and its edition are cited beside it on this page; where none governs, the page says so. Local amendments override model codes — verify against the code in force where you build.
Sources checked 2026-09-02 · in the site-wide review of 2026-09-06 · v1.0.1
Regulatory standards & verification citations1
- Anchor bracket count = ceil(perimeter run length ÷ bracket spacing) + 1, the standard layout method for spacing repetitive structural attachment points
Cite this page
Your workspace
Most jobs need more than one number. Add the calculators you need next and they open right here, underneath this one — your figures stay on screen and nothing is lost to a page change.