Powdered Set Retarders for Gypsum

Retardan® P powdered set-retarders are highly effective solutions to increase the working time of calcium sulphate based plasters and mortars. Products have a wide compatibilty with other additives, don't reduce the final strength of gyspum products and display reduced risk of thermal cracking.


    • Powdered set-retarder.

    • Based on a modified amino acid (pure active substance).


    • Highly effective set retarder for a variety of calcium sulphate binder types. Very efficient even at low dosage.

    • Increase workability time of plasters and mortars up to several hours.

    • Works over a wide pH range and has a high tolerance to changes in pH.

    • Wide compatibilty with other additives, including Sika ViscoCrete® superplasticizers.

    • No reduction in the final strength of gyspum products, unlike several fruit acids.

    • Reduces the risk of thermal cracking.

Typical Applications

    • Manufacture of building plaster, machine and hand applied plaster, smoothing plaster and joint filler for gypsum boards.

    • Production of gypsum boards, fibre boards, blocks and elements.

    • Production of calcium sulphate (self-levelling) screeds.

    • Manufacture of dental and medical plaster.

Also Used In

Featured grades with technical datasheets

A brief overview of the key grades is given below. You will find the Technical Datasheets (TDS) available for download. If you are looking for a Safety Datasheet (SDS) or Product Safety Information (PSI) then please get in touch by phone or via the contact buttons at the top of the page.

Should you not find what you are looking for here then please note that we have further grades available besides these. One of our Technical Sales team will be happy to help. All of the sales team are technically qualified and will be able to advise you on which product to choose. You can either call us, email us or fill in a quick form at the top of the page to get us to call you (Request a Callback). A sample can be requested via the button at the top of the page as well. Please note that by providing us with your contact details, you are agreeing for us to potentially contact you.

Related brochures & technical literature

You will find some of the key product brochures available for download below. There are more brochures available upon request. If you would like to discuss your enquiry further then please get in contact by phone or by filling in the "Request a Callback" form at the top of the page. Someone from the technical sales team will then call you within 24 hours, to discuss your project further.

Retardan® Retarders for Gypsum Binders

Sika Retardan® products have been used in the gypsum industry for decades. They provide an excellent solution to the adjustment of setting time and workability, for a variety of calcium sulphate binder types.

Retardan® Retarders for Gypsum Binders Presentation /




Sika® Performance Additives for Dry Mortar

Sika superplasticizers (ViscoCrete®) and retarders (Retardan®) are widely used technologies in gypsum, mortar and levelling floor screed products. This brochure looks at their use in such applications and explains their benefits.

Sika® Performance Additives for Dry Mortar Brochure /