Sika

Sikasil-728 SL

Self-leveling silicone sealant · US · manufacturer-sourced

Check your container: This countdown is for the Self-leveling silicone sealant variant. Similar-looking versions may have different times.

How long does Sikasil-728 SL take to dry?

Short answer

Tack-free: 115 minutes after application.
Caulk & sealant

Bead cure stages

Skin, tack-free and paint-ready are not the same moment

  1. Gun a continuous bead of Self-leveling silicone sealant
  2. Tool it inside the working time
  3. Keep it dry until the stated water-ready time

This product’s stated stages Quoted at 73°F and 50% humidity

  • Tack-free1 hour 55 min

Worth noticing: The manufacturer states only one timing here (tack-free, 1 hour 55 min); nothing else is inferred.

Common mistake: Showering or painting at skin-over, when the bead is only crusted on the outside.

Caulk & sealant

Bond-strength path

Assembly, handling and full load are different stages

1 · AssembleClean, fit and apply the Self-leveling silicone sealant version correctly.
2 · HoldKeep the joint undisturbed through its set or clamp stage.
3 · LoadUse full cure—not surface firmness—before demanding use.

Time the caulk cure

When did you run the bead?
Conditions that affect drying
Where?
Thickness

Stated times

  • Tack-free115 minutes

From Sika data sheet · checked 2026-10-25. Anything not listed isn’t stated by the manufacturer.

Manufacturer website: usa.sika.com

Conditions & fine print
  • Stated conditions: 73°F (23°C) and 50% relative humidity
  • Times depend on temperature, humidity, joint depth and airflow. Follow the current data sheet.
  • Region US. Formulas can differ between countries; check your container.
  • Tack-free: At 77°F (25°C) and 50% relative humidity.
  • Entered from the cited manufacturer documentation. Check the current label for the exact formula and region. Report outdated information
  • Actual results depend on preparation, thickness, ventilation, temperature, humidity, mixing and substrate.

Confirm this is your product

Closely named formulas, colors and regional versions can use different times. Match these details to your container before starting a countdown.

Exact listing
Sika Sikasil-728 SL
Variant
Self-leveling silicone sealant
Region
US
Listed use
self-leveling sealant, silicone joint sealant, expansion joint
Timed stages recorded
tack free
Source checked
2026-10-25

Documentation: Technical data sheet copy · Version 01.01, October 2018, distributor copy

Condition attached to the stated time: At 77°F (25°C) and 50% relative humidity.

About this product

A self-leveling silicone for horizontal joints. The data sheet lists both a 60 minute skin time (MNA method) and a 115 minute tack-free time (ASTM C-679), and says lower temperature and humidity stretch both.

Using this specific product

Sika Sikasil-728 SL is listed here as the Self-leveling silicone sealant version for self-leveling sealant, silicone joint sealant, and expansion joint. For sealing a joint, the useful question is not simply whether the surface looks finished—it is whether the exact next-action milestone shown above has been reached.

Before you start

  • Confirm the package says Self-leveling silicone sealant; related versions can use different timing.
  • For self-leveling sealant, silicone joint sealant, and expansion joint, pay particular attention to joint depth, tooling, ventilation and exposure to water.
  • At 77°F (25°C) and 50% relative humidity.

How to check readiness

Probe an inconspicuous edge for a continuous skin and follow the stated water-exposure milestone. The data sheet gives a tack-free time of 115 minutes (ASTM C-679).

Avoid this mistake

Surface skin is not the same as through-cure, especially in a deep joint.

Compare with similar products

Keep going

Questions

How long does this product take to dry?

Sika states: The data sheet gives a tack-free time of 115 minutes (ASTM C-679). Conditions: At 77°F (25°C) and 50% relative humidity.. These are the manufacturer’s stated times, not a guarantee.

Why does Sikasil-728 SL list a skin time and a tack-free time?

They use different test methods. The skin time is 60 minutes by the MNA method, and the tack-free time is 115 minutes by ASTM C-679, both at 77°F and 50% humidity. The sheet says lower temperature and humidity extend tack-free and cure rates.

What affects how long this product takes to dry or cure?

Times depend on temperature, humidity, joint depth and airflow. Follow the current data sheet. Follow the product label for your conditions.

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