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How to apply Soudal silicone

Updated: 23 October 2026

You already have a Soudal cartridge and a skeleton gun, and the last bead you ran either leaked at the end or dragged into a ridge because you went back to it too late. How to apply Soudal silicone is mostly the joint you leave behind: old sealant out, the right depth, and a tool across the bead before a skin forms. The eight listings themselves are on the [Soudal silicone comparison](/hub/fillers-adhesives-and-sprays/soudal-silicone). Which family you bought is settled on the buying guide. This page is the sequence. A qualifying purchase can earn a commission at no extra cost to you.

You already have a Soudal cartridge and a skeleton gun, and the last bead you ran either leaked at the end or dragged into a ridge because you went back to it too late.

Our top picks

Soudal Trade multi-purpose white 6-pack

Best overall

Soudal Trade multi-purpose white 6-pack
7.6/10about £21.28
View offer
Soudal Silirub LMN white 300 ml

Rank 2

Soudal Silirub LMN white 300 ml
9.3/10about £8.20
View offer
Soudal Trade multi-purpose white 3-pack

Best value

Soudal Trade multi-purpose white 3-pack
8.0/10about £12.30
View offer
On this page
  1. 1.Prepare the joint
  2. 2.Width, depth, and temperature
  3. 3.Gun, tool, and skin time
  4. 4.While it cures

Prepare the joint

Cut the old silicone out. A new bead over a failed one bonds to the old paste, not to the bath or the frame, and the leak returns at the same end. Pull a blade so you do not gouge acrylic. The joint has to be dry. A film of bathwater is not the moisture silicone needs to cure. Soudal’s Silirub LMN sheet says to clean fresh smears with white spirit or Soudal Surface Cleaner, which is not a substitute for cutting out last year’s bead. Mask both edges. Reviewers of the white trade 3-pack said the paste works with tape if you keep moving. Tool, then pull the tape while the bead is still open. Which cartridge belongs on which substrate is on the Soudal silicone buying guide. Count the tubes before you cut the nozzle.

Width, depth, and temperature

Soudal sizes these joints at about 5 mm to 30 mm, with the width about twice the depth. A wide smear on the tile face, with almost nothing in the corner, looks full and then splits. A backer rod sets the depth so the silicone bonds to the two sides and not to the bottom. The white trade 6-pack is the only listing here that prints a 30 mm maximum gap. Do not copy that figure onto every other ASIN. Both sheets quote about 2 mm of cure in 24 hours. The LMN sheet’s temperature band is about +5°C to +35°C. In a hot bathroom, or on a sunlit roof, the working time collapses, so gun a shorter length and tool it before you continue. Neither family sticks usefully to polyethylene, polypropylene, PTFE or bitumen.
Soudal Trade multi-purpose white 6-pack

Testsieger

Soudal Trade multi-purpose white 6-pack
7.6/10about £21.28
View offer

Gun, tool, and skin time

Cut the nozzle close to the joint width, pierce the inner seal, and push the paste into the corner ahead of you. Skin time is where the families diverge. The Silirub LMN sheet says a skin in about 7 minutes. The Trade Multi-Purpose sheet says about 20 minutes. Only the white 6-pack prints “initial hardening 7 minutes”, and that line must not be copied onto the other trade ASINs. A white LMN bath-to-tile review reported a skin after about 30 minutes in that room. Tool before you see a skin. A rubber blade, pulled once, is what the white 3-pack reviews praise. Pressing a skinned bead again tears the skin and leaves a ridge. Vinegar while that skin forms is a cure question, on the neutral cure or acetoxy silicone page.

While it cures

About 2 mm in 24 hours means a deep joint is not an overnight cure. Keep it dry, and do not paint it: paint does not adhere to silicone. Ventilate. Acetoxy sealant releases acetic acid, and the trade sheet tells you to ventilate. Neutral LMN is not odourless either. Stop when the problem is not a surface bead. A failed sealed unit, structural glazing, and damp behind the bath are outside a cartridge. A neat bead does not repair a dropped tray or a gap wider than the 5–30 mm these sheets describe.

Common questions

Do I cut out the old silicone?
Yes. Bonding new paste to the old bead is why the same corner leaks again. Cut it back to a clean, dry side on both faces of the joint before you mask.
How wide and how deep should the joint be?
About 5 mm to 30 mm, with the width about twice the depth. A backer rod keeps a deep gap from filling solid. The 30 mm figure is printed on the white 6-pack listing in this set, and on the Soudal sheets, not as a dare to bridge a larger crack.
How fast must I tool it?
Before a skin forms. The LMN sheet says about 7 minutes. The trade multi-purpose sheet says about 20 minutes. One Amazon trade listing prints 7 minutes, which does not match that sheet. A bath review of white LMN reported about 30 minutes in that room. If you pause on a hot day, the white 3-pack reviews say the paste drags.
Can I use a wet finger?
You can, and the reviews that did call the finish a sticky mess. Silicone is not a water-based caulk. A rubber blade or a beading tool, used once, is the method the better reviews describe.
How long before it cures through?
About 2 mm in 24 hours on both Soudal sheets. A shallow joint can be through in a day. A deep one takes longer. Do not run the shower the same evening because a listing says 24 hours.
When should a professional take over?
When the sealed unit has failed, the glazing is structural, or the damp is behind the bath rather than at the bead. Also when the joint is wider than these sheets allow, or a written specification already names the product.

Related pages

Soudal silicone for a bathroom

Best Soudal silicone

Soudal silicone

Soudal silicone buying guide: cure, colour and pack

Neutral cure or acetoxy silicone: which Soudal tube

Sources

Public UK sources used for this comparison. Prices, stars and review counts are the amazon.co.uk figures stored for these eight listings. This order is the listing order, not a laboratory test.

  1. Silirub LMN technical data sheet (retrieved 22 October 2026)
  2. Silirub LMN UK declaration of performance (retrieved 22 October 2026)
  3. Trade Multi-Purpose Silicone technical data sheet (retrieved 22 October 2026)
  4. Trade Multi-Purpose declaration of performance (retrieved 22 October 2026)
  5. Soudal UK paint FAQ (retrieved 22 October 2026)
  6. Soudal UK natural-stone FAQ (retrieved 22 October 2026)
  7. GOV.UK construction-product marking table (retrieved 22 October 2026)
  8. Consumer Rights Act 2015 section 11 (retrieved 22 October 2026)