Wood Fillers

About Wood Fillers

Wood fillers are essential products for anyone working with timber, providing quick and effective solutions for repairing holes, cracks, dents, and gaps in wooden surfaces. Whether you're a professional joiner preparing timber for finishing, a carpenter fixing site damage, or a DIY enthusiast restoring furniture, the right wood filler can make the difference between a professional finish and a visible repair. These versatile products are designed to blend seamlessly with wood, accepting stains and paints to match surrounding timber once cured.

The selection at Tooled-Up.com includes everything from quick-drying multi-purpose fillers for general repairs to specialist two-part high-performance formulations for structural applications. Trusted brands like Ronseal, Everbuild, Briwax, and Polycell offer products in various formats including ready-mixed tubs, convenient squeeze tubes, and wax filler sticks for furniture restoration. Whether you're working with softwood or hardwood, interior or exterior applications, there's a wood filler formulated to meet your specific requirements.

Modern wood fillers have evolved significantly, offering improved adhesion, reduced shrinkage, and faster drying times than traditional products. Premium joiners grade fillers provide exceptional workability and can be sanded, stained, varnished, and even drilled once fully cured, making them indispensable for professional tradespeople who demand reliable results on every job.

Jargon Buster

• Two-Part Filler: A high-performance system comprising filler base and separate hardener or catalyst that are mixed together before application. These offer superior strength and minimal shrinkage, ideal for structural repairs and exterior use where weather resistance is essential.
• Joiners Grade: Professional quality filler specifically formulated for timber joinery work, offering excellent workability, minimal shrinkage, and the ability to accept stains and finishes matching the surrounding wood. Premium products from Everbuild exemplify this category.
• Grain Filler: A specialised product designed to fill the natural open grain in certain hardwoods like oak and ash, creating a smooth surface for finishing rather than repairing damage. Particularly useful for achieving glass-smooth finishes on high-end furniture and cabinetry.
• Wax Filler Stick: A solid wax-based filler applied by rubbing directly into minor defects, particularly useful for furniture repair and touching up existing finishes without the need for sanding or refinishing. The Briwax range offers various wood shades for quick colour-matched repairs.
• Stainable: The ability of a cured filler to absorb wood stain in a similar manner to natural timber, allowing the repair to blend invisibly with the surrounding wood tone once finishing products are applied.
• Overfilling: The technique of deliberately applying slightly more filler than needed, allowing for shrinkage during curing and creating a raised surface that can be sanded flush with surrounding timber for a perfect finish.

Who Uses Wood Fillers?

Wood fillers are used daily by a wide range of tradespeople and enthusiasts including:

• Joiners and Carpenters – preparing timber frames, repairing site damage, and filling fixings holes before finishing
• Kitchen and Bedroom Fitters – concealing hinge adjustments, filling damaged melamine, and preparing surfaces for installation
• Furniture Makers and Restorers – repairing defects, filling joints, and restoring antique pieces to their former glory
• Decorators and Painters – preparing woodwork before painting or staining to achieve professional finishes
• Shop Fitters – creating seamless finishes in commercial joinery installations
• Window and Door Installers – repairing damage to frames and making good around installations
• Flooring Specialists – filling gaps between floorboards and repairing damaged wooden flooring
• DIY Enthusiasts – general household repairs, furniture restoration, and home improvement projects
• Property Maintenance Professionals – addressing wear and tear in rental and commercial properties

How to Choose the Right Wood Fillers

Interior or Exterior Use: Standard multi-purpose fillers are suitable for interior applications, but exterior repairs require weather-resistant formulations. Products like Ronseal High Performance Wood Filler with its separate catalyst or Everbuild's 2 Part system are specifically designed to withstand moisture and temperature fluctuations without cracking or shrinking.

Repair Size and Type: For minor scratches and small holes up to 6mm, quick-drying ready-mixed fillers or wax sticks are ideal. The Briwax Wax Filler Sticks Furniture Repair Kit is perfect for small surface repairs. Larger repairs, structural damage, or rot repairs require high-performance two-part fillers that offer greater strength and can be built up in layers without excessive shrinkage.

Finish Requirements: If you're planning to stain the wood, choose a specifically stainable filler that will accept wood stain evenly. For painted finishes, standard fillers like Polycell Polyfilla for Wood work perfectly well. Wax-based fillers are excellent for quick touch-ups on existing finishes without the need for complete refinishing.

Drying Time: Consider your project timeline carefully. Quick-drying formulations can be overpainted in as little as 30 minutes, whilst high-performance systems may require several hours. Premium joiners grade fillers like those from Everbuild strike a balance, offering excellent workability without excessive waiting time between filling and finishing stages.

Application Format: Tubs such as the Ronseal Multi Purpose Wood Filler Tub are economical for larger projects and allow easy application with a filling knife. Tubes with nozzles like the Everbuild Easi Squirt range offer precise application directly into cracks and are convenient for smaller jobs. Wax sticks require no tools and are perfect for site touch-ups and furniture repair work.

Wood Type: Match your filler to the timber species where possible. Available tints including light, medium, dark, mahogany, oak, and white allow you to closely match the wood colour before staining or painting, significantly reducing the visibility of repairs on the finished piece.

Popular Accessories

• Filling Knives and Scrapers – flexible blades from Stanley for smooth application and removal of excess filler
• Sanding Blocks and Abrasive Papers – for smoothing cured filler flush with surrounding timber surfaces
• Wood Stains and Varnishes – for finishing repaired surfaces to match existing woodwork perfectly
• Mixing Boards and Spatulas – essential for preparing two-part filler systems to correct proportions
• Decorators Caulk – for flexible gap filling around timber joints and frames that require movement tolerance
• Wood Hardener – for treating soft or rotted timber before filling to provide a solid substrate
• Methylated Spirit – for cleaning tools and thinning certain filler types where manufacturer recommends
• Primer and Undercoat – for preparing filled surfaces before applying final paint finishes

Safety Information

Most modern wood fillers are water-based and present minimal health risks, but sensible precautions should always be observed. Ensure adequate ventilation when using solvent-based products, particularly in confined spaces. Two-part filler systems may contain isocyanates or other reactive chemicals – always read the manufacturer's safety data sheet and follow COSHH guidelines for handling and storage in accordance with HSE requirements.

Wear appropriate PPE including gloves when working with chemical fillers, and safety glasses if sanding cured filler to prevent dust irritation. Some products are flammable until cured, so keep away from heat sources and naked flames. Store all fillers securely with lids properly sealed, away from children and pets. Dispose of containers and unused product responsibly according to local authority guidelines. When sanding filled areas, use appropriate dust extraction or wear a dust mask to comply with HSE workplace exposure limits for wood dust.

Frequently Asked Questions

Can wood filler be used outdoors?

Standard interior wood fillers are not suitable for exterior use as they lack weather resistance. For outdoor applications, choose a specifically formulated exterior-grade or two-part high-performance wood filler like the Ronseal High Performance Wood Filler with catalyst or Everbuild 2 Part system, which resist moisture penetration, temperature fluctuations, and won't crack or shrink with seasonal movement.

How soon can I sand and paint over wood filler?

This depends on the product type and depth of fill. Quick-drying multi-purpose fillers can typically be sanded after 30-60 minutes for shallow fills, though deeper repairs may take several hours. Two-part systems generally cure faster with less shrinkage. Always check the manufacturer's instructions, and ensure the filler is completely hard before sanding to avoid clogging your abrasive paper or creating an uneven surface.

Why has my wood filler cracked or shrunk?

Shrinkage occurs as water or solvents evaporate during curing, particularly with deep fills or standard fillers. To minimise this, apply filler in layers no deeper than 10mm, allowing each to cure before adding more. Premium joiners grade and two-part fillers available from Tooled-Up are formulated for minimal shrinkage. Slightly overfill repairs to allow for minor shrinkage, then sand flush once fully cured for best results.

Can I stain wood filler to match my timber?

Only fillers specifically labelled as "stainable" will accept wood stain effectively. Products like Ronseal and Everbuild stainable fillers are formulated to absorb stain similarly to natural wood fibres. Standard fillers may not take stain evenly or at all. For best results, choose a filler colour close to your timber, test staining on an inconspicuous area first, and consider using coloured wax sticks for stained finishes where sanding isn't practical.

What's the difference between wood filler and wood putty?

Wood filler is typically water-based, hardens by drying, and is used for repairs that will be sanded, stained, or painted. Wood putty (or stopping) is often oil-based, remains slightly flexible, and is applied after finishing as a final cosmetic touch-up for nail holes and minor defects. For structural repairs and pre-finishing work, wood filler is the appropriate choice for achieving durable, long-lasting results.