Independent comparisons. We may earn from shop links. More info

Solvent weld or push-fit waste pipe

Updated: 23 October 2026

The 40 mm socket in your hand will not go onto the 40 mm pipe on the wall, and both labels can still be right. Solvent weld or push-fit waste pipe is a choice of outside diameter, and of whether you may undo the joint later. Nominal 40 mm solvent-weld is about 43 mm outside. Nominal 40 mm push-fit is about 41 mm outside. They do not push together, and cement does not weld polypropylene. The [drainage pipe comparison](/hub/diy-supplies/drainage-pipe) holds the listings. Confirm the appliance on the [drainage pipe buying guide](/hub/diy-supplies/drainage-pipe/sub/drainage-pipe-buying-guide) before you choose the joint. Sources were checked on 21 October 2026. A purchase from the main comparison can earn us a commission at no extra cost to you.

The 40 mm socket in your hand will not go onto the 40 mm pipe on the wall, and both labels can still be right.

Our top picks

Hibbent Hibbent flexible waste

Best overall

Hibbent Hibbent flexible waste
9.2/10about £11.38
View offer
eco-filtration eco-filtration 43 mm pipe

Best value

eco-filtration eco-filtration 43 mm pipe
8.4/10about £11.99
View offer
eco-filtration eco-filtration 82 mm pipe

Alternative

eco-filtration eco-filtration 82 mm pipe
8.4/10about £19.49
View offer
On this page
  1. 1.Two systems, one nominal name
  2. 2.When push-fit, when solvent weld
  3. 3.If you already have both
  4. 4.Which listing is which joint

Two systems, one nominal name

JDP's push-fit and solvent-weld page prints the outside diameters that the nominal names hide. At 32 mm, push-fit is about 34 mm outside and solvent-weld is about 36 mm. At 40 mm, push-fit is about 41 mm and solvent-weld is about 43 mm. At 50 mm, push-fit is about 54 mm and solvent-weld is about 56 mm. Plastic Supplies Direct gives the same pairs. A 40 mm push-fit socket is made for the 41 mm pipe. Offer it a 43 mm solvent pipe and it stops. Offer a solvent socket the thinner push-fit pipe and the spigot rattles, then leaks, because the cement has no proper gap to fill. The plastics differ as well as the diameters. Push-fit waste in the Polypipe and JDP descriptions is polypropylene with a rubber ring. Solvent-weld waste is ABS or PVC-U, which the cement softens and fuses. Kalsi has a page that talks as if both systems were the same PVC-U or ABS. That line conflicts with JDP and with Polypipe, and it is the line to ignore. If you cement polypropylene, the ring is contaminated and the joint is still a push-fit that no longer seals. Measure across the outside, not the hole, before you buy the next metre.

When push-fit, when solvent weld

Choose push-fit when you may have to take the joint apart. A basin or sink trap that blocks twice a year is a poor place for a weld you can only cut out. Clip the pipe so it cannot creep out of the socket as it warms and cools. Choose solvent weld when the joint should stay and you do not expect to open it. The joint is a fuse, and a mistake is permanent. Dry-fit first. Cure time belongs to the tin. The steps are on how to install a drainage pipe. Building Regulations do not force either system for ordinary domestic waste. Solvent weld on the wrong plastic is not a compliance upgrade.
Hibbent Hibbent flexible waste

Testsieger

Hibbent Hibbent flexible waste
9.2/10about £11.38
View offer

If you already have both

If the basket already holds one solvent length and one push-fit fitting, do not force them into the same socket. A universal compression coupling is the bridge B&Q and Plastic Supplies Direct describe. Check its range against the two outsides you measured, about 41 mm and about 43 mm for nominal 40 mm. A reducer that only changes the nominal size still leaves the families unmatched. Do not wipe solvent cement onto polypropylene. Polypipe states that it does not react. You get a sticky ring and a joint that fails. If you have already contaminated a ring, replace the ring or the fitting.

Which listing is which joint

eco-filtration B0GFWYKRYP is the 43 mm solvent-weld stick, 1 m, at £11.99. The 40 mm in that title is the solvent nominal, not push-fit. The dimensions line also prints 48 × 38 mm, which conflicts with a 1 m length, so measure the pipe when it arrives. The 82 mm length is a larger solvent pipe. Hibbent's flexible waste uses thread adapters and does not convert 43 mm to 41 mm. If your outside is about 43 mm and the joint can stay, use solvent weld. If you need to undo it, buy push-fit to match the pipe you can already separate, or bridge the two with a compression coupling.

Common questions

Which should I use under a sink I might have to undo?
Push-fit. The rubber ring lets you pull the trap off, clear it, and reseat it. Clip the pipe so the joint cannot creep. Solvent weld under a sink you service often means cutting the joint out the next time it blocks.
Which should I use if the run will be hidden?
Solvent weld is the usual choice for a joint you do not expect to open, because the fuse does not rely on a ring staying seated. You still have to dry-fit, support the pipe, and follow the cement tin. Hidden does not mean you should glue polypropylene.
Why will a 40 mm push-fit socket not take my solvent pipe?
Because the outsides differ. JDP puts 40 mm push-fit at about 41 mm outside and 40 mm solvent-weld at about 43 mm outside. The socket is made for one of those, not both. Measure the pipe you have before you buy another fitting with the same nominal name.
Can I put solvent cement on polypropylene?
No. Polypipe states that polypropylene does not react to solvent cement. Push-fit waste is that plastic, with a rubber ring. Cement on it spoils the ring and does not make a weld. Solvent cement belongs on ABS or PVC-U solvent pipe.
What fitting joins the two systems?
A universal compression coupling, sized for the two outside diameters you measured. B&Q and Plastic Supplies Direct both point at a conversion fitting or that coupler. A same-family reducer does not fix a 41 mm pipe in a 43 mm socket.
Is the eco-filtration 43 mm pipe push-fit?
No. The title says 43 mm / 1.5 inch solvent-weld PVC to a 40 mm domestic waste specification. That is the solvent outside diameter. It will not push into a nominal 40 mm push-fit socket. Cement is not in the box.
Do Building Regulations force solvent weld?
No. Both systems are normal for domestic waste when the size, trap seal, and fall are right. The rules do not ban push-fit, and they do not turn a cemented polypropylene joint into a compliant one. Match the plastic and the outside diameter you measured.

Related pages

Best drainage pipe

Drainage pipe

Drainage pipe buying guide: job, size, and outfall

How to install a drainage pipe: dry-fit, then cement

Perforated land drain pipe: slots, fall and outfall

Sources

Public UK sources and the amazon.co.uk listings compared on this page. Listings captured 21 October 2026. Updated 22.10.2026.

  1. Approved Document H (retrieved 22.10.2026)
  2. BSI: BS EN 1401-1:2019+A1:2023 (retrieved 22.10.2026)
  3. JDP: push-fit or solvent weld (retrieved 22.10.2026)
  4. JDP: fixing drainage in a lawn (retrieved 22.10.2026)
  5. Naylor product guide (retrieved 22.10.2026)
  6. Clark Drain: the A15 debate (retrieved 22.10.2026)
  7. Eden District: rainwater soakaway (retrieved 22.10.2026)
  8. GOV.WALES: drains and sewers (retrieved 22.10.2026)