What Are Straps?

Straps are fastening components used to secure electrical raceways, cables, and sometimes boxes or fittings to a mounting surface. In electrical work, the term can cover one-hole conduit straps, two-hole conduit straps, snap-on straps, cable straps, BX or AC style support straps, and similar hold-down hardware. Their job is to support the wiring method without excessive movement and to keep the installation in line with the intended routing. The exact shape varies by application. Some straps wrap partly around conduit, some clamp over cable, and some are formed for direct attachment to framing, strut, or masonry anchors.

Where Are Straps Used?

Straps are used across residential, commercial, industrial, agricultural, and institutional work. Common examples include securing EMT along block walls in service rooms, supporting rigid conduit on exterior runs, fastening PVC conduit before solvent-welded systems are completed, holding armoured cable or flexible conduit near boxes, and tidying branch circuit cable runs in wood-frame construction. Maintenance departments also use straps for retrofit work where existing raceways need added support after equipment changes, panel relocations, or cable rerouting. The right strap depends on the wiring method, the mounting surface, and the environment.

How To Choose Straps

Start with the wiring method. EMT, rigid metal conduit, PVC conduit, flexible metal conduit, liquidtight, armoured cable, and NMD90 do not all use the same strap profile. Next, confirm the trade size. Conduit straps are normally selected by conduit trade size, while cable straps may be selected by cable type or diameter range. Then check the mounting condition. For wood framing, a standard screw-fastened strap may be enough. For concrete or block, you may need compatible anchors. For strut-mounted work, a strap that aligns cleanly with channel hardware can save time. Finally, consider corrosion exposure. Zinc-plated steel may be fine indoors, but damp mechanical rooms, food processing areas, barns, and outdoor work often justify a more corrosion-resistant option. If appearance matters, choose a strap style that keeps the run straight and consistent rather than simply using the cheapest hold-down available.

Trade Rules Of Thumb

As a practical rule of thumb, one-hole straps are often used where speed and easy alignment matter, especially on smaller conduit sizes and short runs. Two-hole straps are commonly chosen when installers want a more rigid hold, better resistance to twisting, or a cleaner look on longer straight runs. Another common trade practice is to avoid forcing a strap that is slightly undersized over conduit or cable just to use leftover stock. That usually slows the job and can mark the raceway or jacket. For exposed work, many electricians also try to keep strap spacing visually consistent even when code would allow wider intervals. These are practical installation habits, not code substitutes. Actual support intervals and permitted methods must be verified against the Canadian Electrical Code, local authority requirements, and product instructions.

Sizing Guidelines

For conduit straps, use the conduit trade size listed for the strap. A 1/2 in strap is intended for 1/2 in trade size conduit, not for matching a measured outside diameter with guesswork. For cable straps, check the cable family and diameter range if provided by the manufacturer. Do not assume a strap that fits one armoured cable brand will fit all constructions equally well. If the strap is too tight, it can deform the cable or make it difficult to maintain a neat run. If it is too loose, the cable may sag or shift. Where multiple conductors or cables are being grouped, use a support method intended for bundling rather than trying to force several cables under a single strap. Any sizing or support decision that affects code compliance, conductor ampacity adjustment, or mechanical protection should be reviewed against the applicable code and manufacturer data.

Common Installation Practices

Installers typically lay out straps so the run stays straight, with supports placed close enough to boxes, bends, and changes in direction to prevent movement during pull-in or normal service. On exposed conduit, straps are usually aligned in the same orientation for a cleaner finish. Fasteners should suit the base material, whether that is wood, sheet steel, structural steel, concrete, or masonry. On PVC conduit, many electricians take care not to overtighten straps, since the conduit needs to be secure without being pinched. On cable work, the strap should hold the cable firmly without crushing the jacket. In corrosive or wet locations, it is common practice to consider the strap, screw, anchor, and mounting surface together so one weak component does not become the failure point. Manufacturer instructions should be followed where a specific strap type is part of a listed support system.

Common Mistakes

One common mistake is treating all straps as interchangeable. A strap that works on EMT may not sit properly on rigid conduit, PVC, or cable. Another is choosing by eye instead of by trade size, which can lead to poor fit and wasted labour. Installers also run into trouble when they use indoor-plated hardware in damp or outdoor areas and later see corrosion staining or strap failure. Overtightening is another issue, especially on PVC conduit and jacketed cable. On retrofit jobs, a frequent problem is adding supports without checking whether the anchor type matches the wall material or whether the existing run needs a different strap style to sit flat. Finally, relying on strap placement habits from one wiring method for another can create inspection issues if support spacing rules differ.

Brand Comparisons

For straps, buyers often focus less on brand loyalty than on fit, finish, coating quality, hole alignment, and whether the part matches the installed system. On many jobs, matching the existing support hardware style is the right call because it keeps the run looking consistent and avoids small fit differences. Some manufacturers are preferred for broad conduit support ranges, while others are commonly chosen for channel and framing systems, cable support hardware, or corrosion-resistant accessories. In this category, the practical comparison is usually between standard plated steel options, heavier formed straps, and stainless or specialty corrosion-resistant versions rather than between heavily differentiated premium brands. If you are maintaining an existing site standard, matching that standard may be more important than changing brands for a small unit cost difference.

Related Products

Straps are commonly purchased with conduit, connectors, couplings, locknuts, bushings, anchors, screws, strut channel, spring nuts, beam clamps, cable staples, and box support hardware. For masonry or concrete work, compatible anchors and drill bits are often part of the same pick list. For cable installations, related items may include cable connectors, anti-short bushings where applicable, stackers, and protective plates. On exposed conduit jobs, layout tools, strut accessories, and proper fasteners often matter as much as the strap itself because they affect alignment and installation time.

Frequently Asked Questions

What is the difference between a one-hole strap and a two-hole strap?

A one-hole strap fastens at a single point and is often chosen for quick installation and easy alignment. A two-hole strap fastens at two points and usually gives a more secure, stable hold, especially on longer exposed runs or where twisting is a concern.

Can I use the same strap for EMT and rigid conduit?

Not always. Some straps are made for a specific raceway profile or trade standard. Even when sizes look close, the fit and hold can differ. It is better to select the strap listed for the actual conduit type and trade size being installed.

How do I know what size strap to buy?

For conduit, buy the strap that matches the conduit trade size. For cable, check the cable type and any stated diameter range. Avoid guessing by visual fit alone, especially on mixed stock jobs where similar-looking products may not clamp the same way.

Are stainless steel straps worth it?

They can be. In dry indoor areas, standard plated steel is often adequate. In wet, corrosive, washdown, agricultural, or outdoor environments, stainless or other corrosion-resistant options may reduce maintenance and replacement work over time.

Can I overtighten a strap?

Yes. Overtightening can deform PVC conduit, mark metal raceway finishes, or damage cable jackets. The strap should secure the wiring method firmly without crushing it. Follow manufacturer guidance where torque or installation limits are provided.

Do straps determine code compliance by themselves?

No. The strap is only one part of the support system. Compliance depends on the wiring method, support spacing, location, mounting surface, fastener type, and the applicable Canadian Electrical Code and local inspection requirements.