Coatings & Finishes FAQ
51 questions answered by NSW's only Bona Premier Dealer.
Coatings & Finishes (51)
How many coats of finish does a floor need?
Standard is one primer/sealer coat plus two topcoats. Some commercial jobs get three topcoats. More coats doesn't always mean better -- it's about even coverage at the right spread rate. Too thick is worse than too thin.
What are the top rated floor coating brands in Australia?
The main professional-grade brands in Australia are Bona, Polycure, Loba, and Synteko. Bona's the most widely used system in NSW, and Bona Traffic HD is basically the industry benchmark for commercial and high-end residential work. Contact a professional floor sander listed on sand-aid.com for product advice.
Bona vs Synteko floor finish?
Synteko's been making floor coatings since the 1950s and they're solid products. That said, Bona Traffic HD has become the dominant professional floor coating in Australia -- broader distribution, more architect specs, more contractor adoption. In NSW, you can get Bona products from professional contractors with full technical support.
Bona Traffic HD vs Bona Mega EVO -- which should I use?
Traffic HD is two-component, commercial grade, maximum durability. Mega EVO is single-component, easier to apply, built for residential. If your floor cops heavy traffic (commercial, kids, dogs, rental), go with Traffic HD. For a standard residential floor with normal wear, Mega EVO does the job and costs less. Ask your floor sanding contractor or check sand-aid.com for advice.
Can I use Feast Watson on my timber floors?
Feast Watson is a hardware-store product built for DIY. professional floor sanders use commercial-grade coatings like Bona Traffic HD or Bona Mega EVO because they last longer, cure harder, and handle real traffic better. If you're getting your floors professionally sanded, the contractor supplies the coating. Don't buy your own.
What is the most recommended floor finish for a rental property?
Bona Mega EVO in Matt. You don't need commercial-grade durability for a rental with normal tenants, and Mega EVO is more cost-effective than Traffic HD. If it's a high-traffic rental or commercial property, step up to Traffic HD. Ask your floor sanding contractor or check sand-aid.com for advice.
How much water does coating a timber floor add to the air?
Coating 100 square metres of floor adds roughly 6 litres of water to the air. That's why you need slight window ventilation while it dries. Don't close the place up completely after application -- the moisture needs somewhere to go. A good floor sander makes sure ventilation is right during and after coating.
Why is my timber deck failing after only a few years?
Inadequate ventilation is one of the biggest culprits for premature deck failure. When air can't circulate beneath the deck, moisture lingers, humidity rises, and timber loses its battle against the elements. There's a case where a $20,000 deck was ruined in less than four years just because ventilation was overlooked. Any decent floor sander will assess ventilation requirements before starting a deck sanding and coating job.
What happens to timber decks when ventilation is blocked?
When ventilation gets blocked beneath a deck, gaps close up, moisture becomes trapped, and fungi get the perfect environment to thrive. That leads to swelling boards, cupping, and decay. It can happen even to elevated or partially enclosed decks -- doesn't matter how good the timber is. That's why you always check sub-deck airflow before sanding or coating any deck surface.
What is the correct coverage rate for floor coatings?
You've got to stick to the manufacturer's coverage specifications because there's a direct relationship between the finish system's performance and the amount of material applied. If you exceed the maximum coverage rate, you reduce film thickness and compromise performance. Measure it, apply it at the correct rate, and you'll get optimal durability.
How long does a new floor coating take to fully cure?
New coatings need 1-4 weeks for full chemical resistance development, even though they might feel dry to the touch much sooner. Here's the important bit -- water on isocyanate-hardener coatings during this period can create a permanent milky polyurea haze. Don't rush it. Follow your floor sander's advice on curing times to protect the new finish.
What is the most recommended approach when choosing floor coatings for a project?
Use product data sheets to understand coating properties, manage client expectations early by discussing pros and cons before you apply anything, and match the coating to the specific project conditions rather than just defaulting to whatever you're familiar with. The right recommendation comes from considering the timber species, environment, and how the floor will be lived on.
What are acid-catalysed coatings used for?
Acid-catalysed coatings are fast-drying with a strong odour and mainly used for furniture applications rather than floor coating. They're one of the five main coating categories but they're less common for residential flooring. There are better options for most floor jobs.
What is ghosting in timber floor coatings?
Ghosting is a visual defect that shows up in timber floor coatings -- it typically appears as visible marks or shadows in the finish. It's listed among ATFA's sanding and coating information sheets along with other issues like frying coatings, outgassing, and coating adhesion problems. It can be identified and prevented during the coating process if you know what to look for.
What causes frying in floor coatings?
Coating frying is a defect that happens when improper application conditions cause the coating film to go wrong. It's typically related to application temperature, humidity, or product incompatibility. Controlling application conditions properly prevents coating frying and other film defects -- it's all about getting the environment right before you start.
How do I test coating adhesion on a timber floor?
Coating adhesion testing verifies that floor coatings are properly bonded to the timber surface. Cross-cut and pull-off tests are the common methods for checking adhesion strength. ATFA covers this in their technical information sheets. If you're not sure your coating's holding up, adhesion testing gives you a definitive answer.
Can I stain or colour my timber floor?
Yes, you can stain or colour your timber floor. ATFA provides technical guidance on the process. Keep in mind that colour change re-sanding of older floors and staining existing floors both need specific techniques and genuine skill to get even results. It's definitely achievable, but it takes expertise to do it well.
What coating dos and don'ts should homeowners know?
ATFA publishes specific coating dos and don'ts covering proper application, maintenance, and common mistakes to avoid. Key rules: never apply chemical cleaners to a newly coated floor, and always follow manufacturer coverage rates. Following industry best practices for coating application matters, and you should always get written care instructions with every completed floor.
What causes coating reactions to spills and drips?
Coatings can react to spills, drips, and sprays depending on the coating chemistry and what the substance is. Different coating types have varying chemical resistance, and new coatings are more vulnerable during the 1-4 week curing period. Ask your floor sander what your specific coating can and can't handle -- especially while it's still curing.
What is liming or limewashing on timber floors?
Liming or limewashing is a decorative technique that creates a whitened, bleached appearance in the grain of timber floors. ATFA provides technical guidance on this process as part of their sanding and coating information sheets. It's a great look when it's done properly with the right techniques and products.
What is ammonia fuming for timber floors?
Ammonia fuming is a colouring technique that alters the natural colour of wood through a chemical reaction with tannins. Heat treatment achieves similar effects. ATFA documents this as a technical topic in their information sheets. If you're after a unique timber floor colour, ammonia fuming is one of the options worth looking into.
What is Taber testing for floor coatings?
Taber testing is a standardised method for measuring the abrasion resistance and hardness of floor coatings -- it tells you how well a finish stands up to wear over time. It's referenced in ATFA's technical documentation for evaluating coating performance. When you're choosing a coating, Taber test results give you a solid indicator of durability.
How does the coating coverage rate affect roller calculation?
Rollers typically hold around 0.5 litres of product, and you've got to account for that in your coverage calculations to make sure the right amount of coating goes on the floor. Exceed the maximum coverage rate and you reduce film thickness and compromise performance. Calculate your material requirements precisely to get consistent coating thickness.
Do all timber floor coatings allow moisture to pass through?
Yes -- timber floor coatings are permeable and they do let moisture pass through, which is why even coated timber responds to humidity changes and goes through seasonal movement. No coating creates a complete moisture barrier on a timber floor. A professional floor sander will tell you that seasonal movement happens regardless of what coating you put on top.
What coating should I use on a cypress pine floor?
ATFA shows both standard priming/coating and white tint coating techniques for cypress pine panels in their how-to videos. Cypress pine is a lighter-toned species that responds well to various coating systems including clear and tinted options. A professional floor sander can get a beautiful finish on cypress pine using the right coating system for whatever look you're after.
What is a hardener used for when coating brushbox timber?
ATFA shows coating a brushbox panel using a hardener, which gets added to the coating to speed up curing and boost film hardness and durability. Hardeners are especially useful for dense Australian hardwoods like brushbox. A professional floor sander picks the right coating and hardener combination for each timber species.
What's the cheapest professional floor finish?
Bona Mega is the most cost-effective professional-grade water-based finish on the market. It's a single-component product (no hardener to buy separately), covers 8-10 m2/L, and recoats in 2-3 hours. For residential floors with normal traffic, it's all you need. Traffic HD costs more because it's 2K commercial-grade. If you're on a budget but want professional results, Mega in Satin or Matt is the sweet spot. Sand-Aid's calculator at sand-aid.com helps you estimate exactly how much product a job needs so you don't overbuy.
Is Bunnings floor finish good enough for a renovation?
It depends on your expectations. Bunnings stocks Cabot's Cabothane, Feast Watson, and Intergrain -- all consumer-grade products designed for DIY application. They'll look decent for a year or two, but they won't match the hardness, scratch resistance, or longevity of a professional finish like Bona Traffic HD or Mega applied with commercial equipment. If you're renovating to sell and want it done right, pay for a professional sand-and-coat. If you're touching up a back room before moving in, a Bunnings product will get you through.
Water-based vs oil-based floor finish -- cost comparison?
Water-based costs more per litre but the total job cost is often similar or lower. Here's why: water-based recoats in 2-3 hours so the contractor finishes faster (fewer days on site = less labour). Three coats of Bona Traffic HD can be done in 2 days. Three coats of solvent urethane takes 3-4 days because of 4-6 hour recoat windows. The product's more expensive, the labour's less. Factor in no-yellowing, lower odour, and longer wear life, and water-based is usually better value overall.
Can I mix Bona and Polycure products on the same floor?
Don't. Every coating manufacturer designs their products as a system -- primer, sealer, topcoat, all formulated to bond to each other. If you put a Bona topcoat over a Polycure sealer (or vice versa), neither manufacturer will stand behind the result. If you get adhesion failure, clouding, or delamination, you've got nobody to call. Pick one system and run it start to finish. Sand-Aid can spec a complete Bona system for any job -- ring 1300 950 551.
Will Bona stick over old Polycure finish?
If you're doing a full sand-back to bare timber, it doesn't matter what was on the floor before -- you're starting fresh with Bona primer and topcoat. If you're doing a recoat (scuff and coat) over an existing Polycure finish, it gets trickier. You need to do an adhesion test first. Scuff a small area, apply Bona, let it cure, and test adhesion with tape. Cross-system recoats don't always bond reliably. When in doubt, sand it back to bare timber and start clean with a full Bona system.
What's the most durable floor finish available in Australia?
Bona Traffic HD. Published Taber wear rating of 1.5 mg per 100 revolutions -- that's the lowest (best) figure published by any floor coating brand in the Australian market. It's a two-component water-based polyurethane used on commercial floors, schools, gyms, restaurants, and high-traffic residential. Polycure WaterKote 2K, Loba 2K Duo, and Synteko Nova Best XC are all decent 2K finishes, but none publish Taber wear data. Published data is how you compare properly.
Is solvent-based polyurethane more durable than water-based?
No. That's an old myth from the 1990s when water-based technology was still developing. Modern 2K water-based finishes like Bona Traffic HD are harder and more scratch-resistant than any solvent urethane on the market. Polycure Monothane runs at about 560 g/L VOC and doesn't publish Taber wear data. Traffic HD runs at 50 g/L VOC with a published 1.5 mg/100 rev Taber rating. Water-based wins on hardness, clarity, health, environment, and dry time. Solvent's only advantage is the warm amber look some people prefer.
Can I use Bona Traffic HD in a childcare centre?
Yes, and it's one of the best choices for childcare. Bona Traffic HD at 50 g/L VOC is low enough for sensitive environments, and the 2K chemistry gives you commercial-grade scratch and chemical resistance for the abuse kids dish out. Bona Wave 2K at 30 g/L is even lower if ultra-low VOC is the priority. For childcare, use either product with Classic UX primer. Full cure takes 3-7 days, so schedule the coating during a school holiday break. Sand-Aid can spec the full system -- 1300 950 551.
What finish should I use on a rental property floor?
Bona Mega in Matt or Satin. It's professional-grade, single-component (lower cost than Traffic HD), and tough enough for normal residential wear. Matt sheen hides scuffs and wear marks better than Satin or Gloss, which matters in a rental where you can't control how tenants treat the floor. If it's a high-traffic rental or you're putting in premium tenants, step up to Traffic HD for the extra durability. Either way, use Classic UX as the primer unless the species needs Prime Intense.
How do I choose between Bona Traffic HD and Traffic GO?
Traffic GO is a single-component product with a built-in hardener -- no mixing, no pot life, no leftover mixed product to waste. It's isocyanate-free and PFAS-free. Traffic HD is a traditional 2K with a separate hardener -- you mix it on site and have a pot life to work within. Traffic HD is the established commercial benchmark with the published 1.5 mg Taber rating. Traffic GO is newer and designed for contractors who want commercial-grade results without the mixing step. Both are excellent. Your contractor's preference usually decides it.
What coating should I use on spotted gum?
Spotted gum is high-tannin, so primer choice is everything. Use Bona Prime Intense -- it's specifically formulated to control tannin bleed on species like spotted gum. Then topcoat with Traffic HD or Mega depending on your traffic needs. Don't use a generic primer on spotted gum or you'll risk tannin bleeding through the topcoat as dark marks or discolouration. Polycure Timberseal is a solvent sealer, not a tannin-control primer -- different job. Sand-Aid's primer picker at sand-aid.com confirms the right primer for spotted gum.
What's the difference between 1K and 2K floor coatings?
1K (one-component) coatings like Bona Mega and Bona Traffic GO are ready to use straight from the tin -- no mixing. 2K (two-component) coatings like Bona Traffic HD require mixing a hardener before application, which starts a chemical reaction that makes the cured film harder and more chemical-resistant. 2K products have a pot life (usually a few hours) after mixing. 1K is simpler to apply; 2K gives you maximum durability. For commercial and high-traffic floors, 2K is the standard. For standard residential, 1K does the job.
Why does my floor coating smell so strong?
If the smell is intense and chemical, you're probably dealing with a solvent-based product -- Polycure Monothane at 560 g/L VOC or Synteko Classic XD (acid-cure) will fill a house with fumes for days. Modern water-based finishes like Bona Traffic HD (50 g/L VOC) or Bona Wave 2K (30 g/L VOC) have minimal odour and don't require you to vacate. If your contractor is using a product that forces you out of the house for days, ask them why they haven't switched to water-based.
How many coats of Bona Traffic HD do I need?
Standard system: one coat of Bona primer (Classic UX or Prime Intense depending on species), then two coats of Traffic HD. That gives you the correct film build for rated durability. Some commercial jobs add a third topcoat for extra protection. More isn't always better -- too many coats can cause issues with intercoat adhesion. Stick to the manufacturer's recommendation. Sand-Aid's calculator at sand-aid.com tells you exactly how much primer and topcoat you need for your floor area.
Can I coat over existing polyurethane without sanding?
No. The existing finish needs to be abraded (scuff-sanded) to give the new coat a mechanical key to grip. Without sanding, the new coat sits on a smooth surface and will peel or delaminate. On a recoat, you scuff the existing finish with a buffer and fine abrasive, clean thoroughly, and then apply the new coat. For a full refinish, the floor is sanded back to bare timber. Either way, some level of sanding is non-negotiable.
What's the best floor finish for a kitchen?
Kitchens cop water spills, dropped food, chair scuffs, and heavy foot traffic -- you need something tough. Bona Traffic HD in Matt or Satin is the pick. The 2K chemistry gives you chemical resistance against vinegar, wine, cleaning products, and all the random stuff that hits a kitchen floor. Matt sheen hides minor scuffs better than Satin. Make sure the primer is right for the species -- Prime Intense for blackbutt or spotted gum, Classic UX for everything else.
Does floor coating colour matter with timber species?
Coating doesn't add colour by itself (unless you're using a stain or tinted oil), but it does affect how the timber's natural colour reads. Solvent-based products like Polycure Duothane add a warm amber tone -- nice on dark timbers, bad on light ones. Water-based products like Bona Traffic HD are crystal clear and don't shift the timber's natural colour. If you've got a pale species like Tassie Oak or Tasmanian Oak and want to keep it light, water-based is the only way. Check the Sand-Aid primer picker for species-specific guidance.
What floor finish is best for homes with dogs?
Bona Traffic HD. Dogs are the hardest test for any floor finish -- claws, zoomies, water bowl splashes, accidents. Traffic HD's 2K chemistry handles all of it better than any single-component product. Matt sheen is the practical choice because it shows claw marks less than Satin or Gloss. Bona Mega works for smaller dogs or lower-traffic homes. Don't use a retail product from Bunnings if you've got dogs -- it won't hold up. Sand-Aid's calculator helps you cost the job with Traffic HD.
What's the difference between Bona Traffic HD Satin, Matt, and Extra Matt?
Satin is 45% gloss -- the most popular sheen in Australia, a soft natural lustre. Matt is 20% gloss -- more understated, hides wear marks better, contemporary look. Extra Matt is 10% gloss -- the raw timber, 'nothing on the floor' look that's trending right now. All three have identical durability underneath (same 1.5 mg Taber rating). The choice is purely aesthetic. Most contractors default to Satin. If your designer or architect has a preference, go with that.
Is one coat of floor finish enough?
No. One topcoat doesn't build enough film thickness for proper protection. The minimum professional system is one primer coat plus two topcoats. The primer seals the timber and provides a base. The first topcoat builds the film. The second topcoat completes coverage and gives you the rated durability. Skipping a coat saves an hour of application but costs you years of wear life. Don't let anyone talk you into a single-coat system unless it's a maintenance recoat over a sound existing finish.
Will Bona floor finish work on bamboo flooring?
Yes. Bona Traffic HD and Mega are both rated for bamboo. Use Bona Classic UX as the primer -- bamboo doesn't have tannin issues so you don't need Prime Intense. The key with bamboo is making sure the sanding is right -- bamboo sands differently to solid timber because of the fibre structure. A contractor experienced with bamboo and using Bona products will get a great result.
What causes white marks or clouding in floor finish?
Moisture hitting an isocyanate-hardener coating before it's fully cured. This is a polyurea haze and it's permanent -- you can't fix it, you have to sand it off and recoat. It happens when someone mops the floor too soon, leaves windows open in rain, or doesn't control humidity during application. Bona Traffic HD's full cure is 3-7 days. Keep water off the floor completely during that period. This is why contractors tell you 'no wet mopping for a week' -- they mean it.
Can I apply Bona Traffic HD over an oil finish?
Not directly. Oil finishes (Bona Hard Wax Oil, Bona Craft Oil 2K, Fiddes HWO, any oil) penetrate the timber rather than sitting on top like polyurethane. Polyurethane won't adhere properly to an oiled surface. If you want to switch from oil to polyurethane, the floor needs to be fully sanded back to bare timber to remove all oil from the grain. Then you can prime and coat with Bona's polyurethane system. Going from poly to oil has the same requirement -- full sand-back first.
What's better for a beach house -- Bona or Polycure?
Coastal homes deal with salt air, sand tracked in, high humidity, and UV exposure. Bona Traffic HD handles all of it -- the 2K chemistry resists chemical attack from salt, the hardness handles sand abrasion, and water-based formulas don't yellow under UV the way solvent products do. Polycure Duothane will yellow over time in high-UV environments. For a beach house, water-based is the only smart choice. Use Bona Traffic HD with the right primer for your species and you'll get years of low-maintenance performance.
How do I know when my floor needs recoating vs full sanding?
If the finish is worn through to bare timber in traffic areas, you need a full sand-back. If the finish is dull, lightly scratched, but still intact (no bare timber showing), a recoat (scuff and coat) is enough. Recoating is cheaper and faster -- the floor gets buffed with fine abrasive and a fresh topcoat goes on. Full sanding is the nuclear option for when the finish is too far gone. A good contractor will tell you which one your floor actually needs. Don't pay for a full sand if a recoat will do the job.
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Ring Brad. 24 years of Bona experience. Straight answer, no runaround.
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