FAQ
Frequently asked questions:
For questions relating to returns and delivery: the dedicated page is here.
How should we understand the sizes of fittings and Pipes?
The second digit of the dimensions in millimetres corresponds to the outside diameter of the Pipes.
For example:
- for a 3/4'' pipe i.e. 20x27mm the outside diameter of the pipe will be 27mm.
- for a 1/2'' elbow fitting i.e. 15x21mm the outside diameter of the pipe that can be screwed into the elbow is 21mm
Correspondence table for plumbing fitting sizes in inches and mm:
| Size inch |
Size mm |
Diameter outside |
| 3/8" | 12/17mm | 17mm |
| 1/2" | 15/21mm | 21mm |
| 3/4" | 20/27mm | 27mm |
| 1" | 26/34mm | 34mm |
| 1"1/4 | 33/42mm | 42mm |
What to clean my black cast iron fittings and black steel Pipes with?
Cleaning can be carried out with a suitable degreaser or more simply with F petrol or acetone. The cast-iron and steel pipes and fittings sold as spare parts are coated with a film of grease to protect the parts.
What finish on black cast iron and black steel?
A wide variety of finishes are available. If you want to keep the raw look of the pieces, it is possible to opt for a wax or varnish.
The spray or aerosol varnish finish is the easiest to apply.
All our assembled products are finished with a varnish, to preserve the small defects of the parts and the shine of the fittings.
For a more uniform appearance you can opt for a suitable paint or a hematite mat for example.
What diameter pipe should I choose for my project?
Diameters 15x21mm (outside diameter of pipes 21mm) and 20x27mm (outside diameter of pipes 27mm) are suitable for most projects. Be careful not to think too big, as the 34mm and 42mm diameters can quickly prove too big and heavy. If you're aiming for a massive, spectacular effect, they are, of course, perfect.
A little tip, to assess the size:
- a 21mm diameter corresponds to a 10 centime coin +1mm,
- a diameter of 27mm corresponds to a 2 euro coin +1mm.
The easiest way is to roll a sheet of paper around the coin to estimate the diameter.
How to assemble threaded pipes and fittings
As part of a decorating project, you naturally don't need to worry about watertightness; manual screwing, with no additions of any kind is usually more than enough. If you're having trouble aligning the fittings where you want them, check out our blog post on the subject. Be careful, it may take a bit of strength!
What diameter is a 3/8" plumbing pipe?
| Size in inches | Size in mm | Outer diameter mm | Size DN |
| 3/8 | 12x17 | 17 | 10 |
What diameter is a 1/2" plumbing pipe?
| Size in inches | Size in mm | Outer diameter mm | Size DN |
| 1/2 | 15x21 | 21 | 15 |
What diameter is a 3/4" plumbing pipe?
| Size in inches | Size in mm | Outer diameter mm | Size DN |
| 3/4 | 20x27 | 27 | 20 |
What diameter is a plumbing pipe 1''?
| Size in inches | Size in mm | Outer diameter mm | Size DN |
| 1 | 26x34mm | 34mm | 25 |
What diameter is a plumbing pipe 1''1/4?
| Size in inches | Size in mm | Outer diameter mm | Size DN |
| 1 1/4 | 33x42mm | 42mm | 32 |