Sponge floats are commonly used in rendering to rub up and float the surface, helping to achieve a consistent, even texture on freshly applied materials. By bringing a small amount of moisture to the surface, sponge floats allow the renderer to rework and refine the finish, making them especially effective after the initial set but before final finishing.

Key benefits include:

• Rubbing up base coats to close in the surface
• Floating renders to remove trowel marks and imperfections
• Creating a keyed surface for top coats or decorative finishes
• Achieving a uniform texture across large areas

They’re an essential tool for renderers looking to produce a clean, professional finish, particularly on monocouche and sand and cement render systems.

The best sponge float for plastering depends on the stage of the job and the surface material. REFINA offers a professional range of sponge floats, including:

Natural Rubber Sponge Floats: Fitted with an orange rubber sponge, these are ideal for working with gypsum plasters, providing excellent control during the finishing stage.

Dense Rubber Sponge Floats: Built for durability, these floats are perfect for abrasive surfaces like cement-based renders and hard backing coats.

Foam Sponge Floats: Featuring a white sponge foam, these versatile floats can be used on finish plasters, renders, and cement-based materials, making them a great all-rounder.

Duren, Latex & Felt Sponge Floats: Designed for low absorption, these floats are ideal when working with traditional plasters and heritage materials, helping to maintain material consistency during finishing.

Cellular Sponge Floats: A premium option for floating render surfaces and cleaning grout joints, offering fine control and excellent moisture management.

Abrasive Sponge Floats: Best suited for emulsifying epoxy grouts and removing excess material, these floats are tough and effective on more demanding jobs.

Using a sponge float helps improve the finish by:

• Removing surface imperfections left by trowels
• Opening the surface slightly, which can aid the final trowelling process
• Enhancing the overall flatness and consistency of the plaster or render
• Reducing surface suction, making the next coat easier to apply

Sponge floats come in several variations tailored to different tasks:

Natural Rubber Sponge Floats: Ideal for finishing gypsum plasters, smoothing skim coats, and bringing moisture to the surface for easier final trowelling.

Dense Rubber Sponge Floats: Best suited for floating cement-based renders, working on abrasive backing coats, and preparing surfaces for final finishes in tough site conditions.

Foam Sponge Floats: A versatile choice for rubbing up finish plasters, floating sand and cement renders, and general-purpose smoothing across various surfaces.

Duren, Latex & Felt Sponge Floats: Designed for working with traditional lime plasters, heritage restoration projects, and low-absorption plaster systems where moisture control is key.

Cellular Sponge Floats: Used for floating external renders, cleaning grout joints, and preparing render surfaces before scraping or finishing.

Abrasive Sponge Floats: Perfect for removing excess epoxy grout, emulsifying stubborn grout residues, and cleaning tough surfaces during tiling or finishing work.

Choosing the right type ensures the best finish for your project.

Sponge floats are typically used after the plaster or render has started to firm up—not while it’s too wet. Using the float at this point:

• Helps flatten and level the surface
• Prepares it for final trowelling
• Reduces trowel marks or lines

Timing is crucial, too early, and the plaster will drag; too late, and it may have set too hard to work.

In tiling, a sponge float (or grout float) is used to press grout firmly into tile joints and then wipe away excess grout. It ensures the joints are filled properly, reducing air pockets and increasing durability.

A sponge float is key for:

• Smooth, consistent grout lines
• Removing surplus grout without disturbing joints
• Minimising haze or residue on the tile surface

For grouting, the best float typically has:

• A dense, closed-cell rubber face – Prevents absorption and makes cleaning easier. Our range of cellular sponge floats offer superior performance when it comes to cleaning joints after grouting and floating render materials thanks to their high absorbent sponges. Open and square cut (cross cut) sponges are also available.
• Firm edges – To press grout fully into joints
• A comfortable handle – For prolonged use without strain

REFINA’s rubber grout floats are engineered for professional performance across wall and floor tiling applications.

In tiling, a sponge float is used to clean excess grout from the tile surface after it has been applied with a grout float. The soft sponge helps wipe tiles clean without disturbing the grout lines and prevents scratching, especially on delicate surfaces.

Yes, effective sponge floating relies on light, circular motions and proper timing. Key tips include:

• Use clean water – Rinse your float frequently to avoid smearing grout or plaster
• Don’t press too hard – Let the sponge do the work to avoid pulling material out
• Wring out excess water – A damp, not soaked, float gives better results
• Work methodically – Focus on small areas to maintain consistency

With the right technique, a sponge float can dramatically enhance the quality of your finish.