Silicone and Sealant Cartridge Calculator (Caulk for a Joint)
How many cartridges of silicone, caulk or sealant a joint takes, from its width, depth and total length, and how many metres one cartridge runs.
Results
The dashed line marks the value you entered.
What this tool does
A joint is a long thin box, and the neat part is the units: width in mm × depth in mm × length in metres equals the volume in millilitres. A 6 × 6 mm joint takes 36 ml per metre, so a standard 310 ml cartridge runs about 8.6 m — in practice a bit less, because the nozzle and the last of the tube are lost. For wider movement joints manufacturers commonly ask for a depth of around half the width, set with a backer rod, and a sealant that bonds on two faces only, so check the datasheet for the ratio and the limits of your product.
Formula
volume (ml) = width (mm) × depth (mm) × length (m) · cartridges = ⌈volume × (1 + waste) ÷ cartridge size⌉
Variables
| Symbol | Meaning | Unit |
|---|---|---|
jw | Width of the joint | mm |
jd | Depth of the sealant | mm |
jl | Total length of joint | m |
cv | Size of a cartridge | mL |
ws | Extra for waste and the nozzle | % |
N | Cartridges to buy | — |
V | Volume of sealant in the joint | mL |
M | Joint one cartridge fills | m |
Worked example
- Width of the joint6 mm
- Depth of the sealant6 mm
- Total length of joint10 m
- Size of a cartridge310 mL
- Extra for waste and the nozzle10 %
- Cartridges to buy2
- Volume of sealant in the joint360 mL
- Joint one cartridge fills8.6 m
Limitations
- Always order a little more material than the calculated quantity. Cuts, breakage and pattern matching create waste that depends on the shape of the job.
- Coverage and consumption figures vary between products. Take the values from the manufacturer's datasheet for the product you are actually using.