How to Create Longer PVC Pipe Lengths Using Internal PVC Couplings
If you’ve ever tried building with Furniture Grade PVC pipe, you’ve likely run into one frustrating issue: finding pipe lengths long enough for your project without paying high shipping costs.
Here’s the challenge—shipping carriers apply steep handling fees to packages over 48" long, and those costs continue to rise. To keep prices reasonable, FORMUFIT limits standard pipe lengths to a maximum of 5 feet (60"). To further reduce fees, we also offer 40" pipe options that help customers avoid these surcharges.
While these shorter lengths help reduce costs, they can create limitations when building larger projects like patio covers, greenhouses, or 9-square games. But there’s an easy fix: FORMUFIT Internal PVC Couplings. These clever connectors let you join pipe segments internally, extending your pipe to any length you need—without bulky seams or external fittings.
If your project requires substantial pipe quantities, you can order 10’ and custom-cut lengths on our bulk site, FORMUFIT Direct.
Why Use Internal PVC Couplings?
The Internal PVC Coupling is a compact connector that joins two pieces of Furniture Grade or Schedule 40 PVC pipe from the inside. Unlike standard couplers, it slides inside the pipe, maintaining the same outside diameter and leaving a smooth, nearly invisible connection. Once cemented in place, the bond is strong and permanent.

Internal PVC Couplings are available in all FORMUFIT colors and stocked in 1/2 in., 3/4 in., 1 in., and 1-1/4 in. sizes. They’re sold individually on formufit.com, so you can order exactly what you need for your project.
How to Create Longer PVC Pipe Lengths
Here’s a step-by-step guide to combining standard PVC pipe sections into any length you need using Internal PVC Couplings.
Determine the Lengths You Need
Decide the total pipe length required for your project—6’, 7’, or any custom size. Calculate how to achieve that using available 40” or 60” pipe sections.
Each Internal PVC Coupling adds about 1/8” to 1/4” to the overall pipe length. Factor this into your measurements for precise cuts.
Gather Your Materials
- 40” or 60” PVC pipe segments
- Internal PVC Couplings
- Measuring tape
- Marker or pencil
- Hacksaw or pipe cutter
- PVC cement (optional for permanent bonds)
Measure and Cut
- Measure each pipe section to achieve your final length.
- Mark your cut points clearly with a pencil.
- Cut using a hacksaw or PVC cutting tool.
Make straight, 90° cuts so the coupler fits evenly inside the pipe for a tight, seamless connection.
Prepare the Pipes and Couplings

- Remove burrs or debris from the pipe interior to ensure a snug fit.
- Dry-fit the coupling into one pipe to test alignment.
- If insertion is tight, slightly bevel the inner edge using a knife.
- Tap gently with a mallet to seat the coupling evenly inside the pipe.
Cement the Pipes (Optional but Recommended)
For permanent, structural connections, use PVC cement to fuse the coupling and pipe together. This creates a strong, one-piece length of pipe.
- Apply PVC cement to the inside of one pipe end.
- Insert the coupling fully and wipe off excess cement.
- Apply cement to the second pipe end, slide it onto the coupling, and hold for 30 seconds.
Skip the cement if you want detachable sections or if the fit is already tight enough.
Check Alignment

- Ensure the pipes are straight before the cement fully sets.
- If it’s slightly too long, remeasure and trim as needed.
- Let the joint cure for about 30 minutes before use.
Put Your Pipes to Use
That’s it—you’ve made your own custom PVC pipe lengths! Use them in furniture, greenhouse frames, or large-scale DIY builds where longer segments are essential. Internal PVC Couplings make it simple, seamless, and affordable to go beyond shipping-size limits.
2 comments
Could you make other fittings internal like the coupler. Specifically, the 3/4 Tee, Elbow and 5 way cross in black. What would the bulk cost be?
Can you use standard pvc pipe lenghs from store to assemble with your fittings?