Plastering Question

Do you need to add waterproofer to k rend?

6 Answers

Best Answer

K-rend is a silicone range which incorporates silicone water repellents as an integral part of the cement based render system. The silicone technology imparts a high degree of water repellence to the render surface whilst allowing water vapour to pass through the render and let the substrate breath.

The water repellent surface ensures a freshly rendered appearance for prolonged periods. The finish is drier and thus more resistant to algae growth.

Depending on the condition of the building, area in which is to be rendered. There are several ways in which the building has to be prepared before receiving the top coat of K-rend.

All loose and flaking paint is scraped or grinded back before receiving a scratch coat of polymer render with WATERPROOFER in.

Pre-existing render or pebble dashing

Blown pebbledash or crumbling render is to be removed and the bare surface is washed down. As with painted surfaces there is a scratch coat of polymer render with waterproofer applied

Fixing corner & bellcast beads

U.P.V.C corner and bellcast beads are fixed to doors, windows and corners during or after the scratch coat is applied, thus leaving clean edges when top coat applied.

K-rend application

Once the defected render or paint work is removed and the scratch coat has been applied, the surface is ready to receive the top coat of K-rend coloured mortar system.

Using a darby or straight edge the top coat of K-rend is applied to the ready prepared surface at a thickness of 16mm, from this there are a choice of two finishes to the render.

Sponge finish

At the correct time a sponge float is used in tight circular motions which leave a smooth uniform finish.

Scratch finish

After 2 to 36 hours a float known as a nail float is used in a tight circular motion leaving a rough uniform finish.

Answered 2nd Dec 2011

JNR - Plastering services

Member since 16 Apr 2008

No. K Rend repels water thats why it changes colour when wet. It has a lime and silicone base that waterproofs and also allows breathing at the same time. There are also different types of backing ( scratch coats ) available depending on what the building is constructed from, which again assist in its waterproofing. Excellent stuff, used many times to help resolve damp problems and has never failed. Dependent on substrate and type of K rend used, it is usually shower proof in around 2 hours.

Answered 3rd Dec 2011

J Wright Property Solutions

Member since 7 Sep 2008

I have used K-rend on many contracts. Water proofer is not required as it is a pre-mixed additive in the material. Its just mixed with water. Waterproofer would be required in any undercoats.

Answered 3rd Dec 2011

Paul Meehan Plasterer

Member since 25 Nov 2011

K-Rend incorporates silicone water repellents as an integral part of the cement based render system.

Answered 2nd Dec 2011


Member since 29 Oct 2008

hi merrice
no,simply because, it is already acrillic based, however you can add a
plasterciser to help its density if your applying it by hand, to help it spread
better, but however its better to use a g5- g6 machine and spray it on.
hope this helps.

Answered 3rd Dec 2011

M J Plastering

Member since 18 Aug 2011

You do not need to add waterprooer the waterpoofer is in the K rend
Regards Daniel

Answered 2nd Dec 2011

Findon Building Company

Member since 17 May 2009

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