Underground Electrical & Broadband
Conduit Duct Spacers
Conduit duct spacers are interlocking supports that hold underground conduit in precise horizontal and vertical alignment while a duct bank is assembled, poured, and backfilled.
Also called conduit chairs, duct bank spacers, or trench spacers, these fittings keep conduit evenly separated so concrete or backfill flows around every duct and the bank cures straight. Innovative Plastics duct spacers snap together vertically and horizontally for fast field assembly with no banding required, and are molded from high-impact polymers that survive the pour.
The line covers two roles: base spacers that set the bottom row off the trench floor and intermediate spacers that stack the rows above it, plus single-tier clip spacers for lighter exposed and underground runs. Together they handle duct sizes from 1" through 8" with 1.5"–3" separation, in both encased-burial and direct-burial installations.
Need them ready to drop in? Pre-assembly is available — just ask. Browse the two product families below, or read our guide to duct bank spacing to choose a configuration.
Duct Spacers products
2 products
Duct Spacers Base & Intermediate
Snap-together conduit spacers that accommodate multiple alignment options, providing exceptional strength and unmatched resilience.
View specifications
Duct Spacers Clip Spacers
Easy-to-use, snap-in conduit clip spacers designed for both exposed and underground conduit installations.
View specificationsSealing devices vs. duct spacers vs. caps
Three product families cover the underground conduit lifecycle: sealing devices protect open conduit, duct spacers align conduit during the pour, and caps close conduit ends.
| Family | Primary purpose | Material | Size range |
|---|---|---|---|
| Sealing Devices | Seal and protect open conduit, ducts, and innerduct | Low-density polyethylene (LDPE) | 1"–8" |
| Duct Spacers (this page) | Hold conduit in alignment during trenching and backfill | High-impact polymer / ABS resin | 1"–8" duct, 1.5"–3" separation |
| Caps | Close conduit ends; riser caps add a rope-tie loop for mule tape | High-impact PVC | ½"–6" |
FAQ
Frequently asked questions
- What is a conduit duct spacer?
- A conduit duct spacer (also called a duct bank spacer or conduit chair) is a two-piece interlocking support that holds underground conduits in precise horizontal and vertical alignment while a duct bank is assembled, encased in concrete, or direct-buried.
- Do duct spacers require banding?
- No. Innovative Plastics base and intermediate spacers interlock vertically and horizontally so the assembly locks together without banding, which speeds field assembly and keeps spacing consistent through the pour.
- What is the difference between base and intermediate spacers?
- Base spacers set the bottom row of conduit off the trench floor; intermediate spacers stack on top to build additional rows. They share the same interlocking design so a duct bank of any height assembles from the two parts.
Guides & resources
- Conduit Duct Bank Spacing: Intervals, Separation, and Cover How to space conduit in a duct bank — spacer intervals along the run, separation between conduits, and concrete cover for encased and direct-burial installations.
- How to Install Conduit Duct Spacers A step-by-step guide to assembling base and intermediate conduit duct spacers into an aligned duct bank for encased or direct-burial installation — no banding required.
- How Many Duct Spacers Per 100 ft? How to estimate duct spacer quantity for a conduit duct bank — spacer sets per 100 ft at 5–10 ft intervals, with a free calculator. Confirm against your project specification.
- A Made-in-USA Alternative to Wunpeece Duct Spacers Innovative Plastics base, intermediate, and clip duct spacers are an American-made alternative to Wunpeece-style interlocking duct spacers — same job, sizes 1"–8", no banding, in stock by the case.
Need specs, samples, or a distributor?
Add sizes to a quote request, or contact our sales team for volume and distributor pricing.