LH-HY 樂熹鴻業有限公司Premium Korean
Silicone Sealants 中文

Korean-made silicone sealants for Hong Kong windows, glass and façades

LH-HY is the sole authorised distributor of WACKER silicone sealants in Hong Kong and an authorised distributor of KCC. We also supply TOPP, our own weatherproofing silicone made for us by WACKER in Korea.

See the range
Animation: a cartridge lays a silicone bead along the joint between an aluminium window frame and the glass
Sole authorised distributor in Hong KongLUCKY-SILICONE LC909N glazing silicone Our own brand, made for us by WACKERWeatherproofing silicone for exterior and panel joints Authorised distributor in Hong KongKORESEAL SL907 Premium

Find the right sealant for the job

Tell us what you are sealing and we will point you to the right product. These are the common jobs our customers in Hong Kong use them for.

Aluminium windows and doors

Glazing and frame joints that face sun and driving rain.

LC909NTOPPSL907 Premium

Glazing

Bedding and capping glass in window frames, shopfronts and partitions.

LC909NSL907 Premium

Exterior walls, panels and curtain walls

Window perimeters, aluminium panels, curtain wall and expansion joints outside.

TOPP

Our range

Three sealants, all made in Korea. Colour dots show the colours we stock. Ask us about other colours.

WACKER Sole authorised distributor in Hong Kong

LC909NNeutral cure glazing silicone

General-purpose sealant for window glazing and aluminium, UPVC and wooden windows.

White / Grey / Black / Bronze / Clear
G-30SHM
Specifications and downloads – LC909N

TOPP Our own brand, made for us by WACKER

TOPPNeutral cure weatherproofing silicone

Exterior and panel-joint weatherseal with ±30% movement. Tested to BS 5889 and BS 3712.

Champagne / White / Grey / Black / Bronze
KS F 4910 F-25HMBS 5889:1989BS 3712:1985Low VOC
Specifications and downloads – TOPP

Compare the three

LC909NWACKERTOPPTOPPSL907 PremiumKCC
TypeNeutral cure glazing siliconeNeutral cure weatherproofing siliconeNeutral cure weatherproofing silicone
Best forWindow glazing; aluminium, UPVC and wooden windowsWindow perimeters, aluminium panels, curtain wallsGeneral glazing, windows and doors
Movement capability20%±30%Ask us
KS F 4910G-30SHMF-25HMAsk us
British standards—BS 5889, BS 3712 (tested 2025)—
ColoursWhite, grey, black, dark bronze, transparent, translucentChampagne, white, grey, black, bronzeWhite, clear
Made byWACKER, KoreaWACKER, Korea, for LH-HYKCC, Korea

Why contractors choose LH-HY

  • AuthorisedWacker Chemicals Korea has certified LH-HY as its authorised distributor in Hong Kong. We are also an authorised KCC distributor.
  • BS 5889TOPP passed every BS 5889 and BS 3712 test at Fugro's Hong Kong laboratory in 2025.
  • KS F 4910LC909N was tested in 2025 to the Korean standard for building sealants (class G-30SHM). TOPP is rated F-25HM.
  • Made in KoreaEvery sealant we sell is made in Korea by WACKER or KCC.
  • LocalOffice on Nathan Road, Mong Kok. Quotes in Chinese and English.
WACKER LC909N, TOPP and KCC SL907 silicone sealant cartridges
LC909N, TOPP and SL907. All three are made in Korea.

Trusted by Hong Kong's window trade

Two of the names Hong Kong's aluminium window industry relies on specify our sealants.

Designated silicone sealant partner of 升威 LE-RELAX

Since 1986, LE-RELAX has made aluminium windows, doors and glass in its own 120,000 m² factory in Zhongshan, from glass processing to final assembly. It is a Housing Authority approved aluminium window supplier, a founding member and chair of the Hong Kong Aluminium Windows & Doors Association, and has three stores in Hong Kong.

Visit le-relax.co

Official silicone sealant partner of the Hong Kong Aluminium Windows & Doors Association

Association members fit our sealants on aluminium windows and doors across Hong Kong.

View test reports and leaflets

Common questions

See all questions and answers

What is the difference between neutral cure and acid cure silicone?

Acid cure (acetoxy) silicone releases acetic acid as it cures, which is the vinegar smell. It can corrode metals and react with alkaline surfaces such as concrete and mortar. Neutral cure silicone does not release acid, so it is the safer choice for aluminium window frames, metal, concrete and most building work. LC909N, TOPP and KCC SL907 are all neutral cure.

Should I use LC909N or TOPP?

WACKER LC909N is a general-purpose glazing sealant for setting glass and sealing aluminium, UPVC and wooden windows (movement capability 20%, KS F 4910 G-30SHM). TOPP is a weatherproofing sealant for joints that move more and face the weather: window perimeters, aluminium panels and curtain wall joints (movement capability ±30%, KS F 4910 F-25HM, tested to BS 5889 and BS 3712). If you are not sure, WhatsApp us a photo of the joint.

How long does the silicone take to dry?

For LC909N and TOPP, a skin forms in about 10 minutes and the sealant cures inwards at about 2 mm a day, measured at 23 °C and 50% relative humidity. A deeper joint takes longer to cure all the way through, and cold or dry weather slows it down. Avoid moving or loading the joint until it has fully cured.

What is BS 5889 and which product meets it?

BS 5889 is the British Standard specification for one-part, gun-grade silicone building sealants, and Hong Kong specifications often refer to it. In 2025, Fugro's Hong Kong laboratory tested TOPP to BS 5889:1989 and BS 3712:1985, and it passed every test. You can download the report from the technical data page.