Polyurethane varnish for wood can be used on doors, window frames, floors and other joinery structures. Providing a tough finish, they are great for protecting wood against abrasive scuffs, knocks and scratches. So, if you are looking for more a durable and protective wood finish than wood oils offer, for bare woods or previously stained/varnished surfaces, Rawlins Paints have a great selection of polyurethane varnishes from Blackfriar, Coo-Var, Jotun and Mathys. Rawlins Paints now stock newer, advanced, next-generation wood products from Rubio Monocoat that are much more user-friendly and combine the advantages of oils, waxes, and varnishes in one tin. More on these further below.
Don’t forget that Rawlins Paints also stock a wide range of fire retardant varnishes for wood, should you require improved fire protection at your work premises or commercial/private property. These coatings will maintain the look of timber surfaces, whilst providing up-to 60 minutes’ fire resistance.
- What is Polyurethane Varnish?
- Polyurethane Varnishes at Rawlins Paints
- Next-Generation Wood Varnishes
- Technical Support
What is Polyurethane Varnish?
Polyurethane varnishes are super-tough ‘coatings’ popularly used as a finishing layer for protecting interior and exterior wooden floors, stairs and other surfaces prone to pedestrian wear and tear – some products can also be used on chipboard, plywood, hardboard, and parquet surfaces. Easy to use, with water-based polyurethane varnishes containing lower VOCs than solvent or oil based versions, and more durable than standard wood varnishes, they are a popular choice for woodworkers, furniture makers and restorers, and joiners. From floors to cabinets, and stairs to bar surfaces, polyurethane varnishes can deliver excellent protective qualities in gloss, matt or satin finishes.
A polyurethane finish can best be described as a hardening liquid plastic coating. Frequently used in renovation, restoration and repair work within libraries, hotels, restaurants, bars, cafes and independent boutique retail shops, the finished coat is designed to provide long-lasting, durable and hard-wearing protection.
Today, water-based polyurethane varnishes differ from older production of varnishes, in that they produce lower VOCs than resins, oils and solvents previously used. Many manufacturers produce clear polyurethane varnishes, but they are also available in the following tints and shades:
- Antique Pine
- Light Oak
- Medium Oak
- Dark Oak
- Golden Oak
- Dark Mahogany
- Spanish Mahogany
- Deep Red Mahogany
- Golden Teak
- Burmese Teak
- Dark Jacobean
Although labelled as a clear polyurethane varnish, as with any varnish, the finished effect depends on the type of wood it is applied to – with some darkening the wood grain.
- Solvent and oil-based polyurethane varnishes can dry to leave a slightly amber finish, warming up the wood and its grain. Being slower to dry than the water-based products, it of course means that there needs to be longer periods of time left between additional coats.
- These products contain higher VOCs, and application equipment requires cleaning up with solvent.
- Water-based polyurethane varnishes have a milky tint in colour, but will dry to leave a clearer, more transparent finish than solvent-based products – preferable to some users.
- Application equipment for water based polyurethane varnishes can be cleaned-up with soap and water – always refer to product datasheets for manufacturer specific recommendations for cleaning and storage.
The choice of finishes available – gloss, matt and satin – typically rely on user preference.
Solvent and oil-based polyurethane varnishes are stronger and more durable than water-based ones, with products stocked at Rawlins Paints focusing on commercial and trade usage on floors and within hospitality sector, rather than domestic and DIY projects.
There are alternatives to polyurethane varnishes for use within the marine sector and for wooden surfaces that are required to be fire retardant.
What is Polyurethane Varnish Made Of?
Polyurethane that is used in floor varnishes, for example, are water or solvent based plastic resin coatings, typically clear, that deliver a specific finish on wood – this differs from other types of polyurethane application use, including flexible/rigid polyurethane foam, thermoplastic polyurethane (TPU), reaction injection molding (RIM), and other automotive, electronic, medical or packaging varieties.
What Does Polyurethane Do?
Most wood finishes penetrate the wood surface and soak into the substrate, including some varnishes. Polyurethane wood varnish dries on top of the surface, protecting it with an anti-abrasive sealed layer. Primarily clear/translucent/transparent ‘topcoats’, polyurethane varnishes:
- Dry quicker than standard wood varnishes
- Contain a water or solvent-based plastic resin, compared to standard varnishes containing resins, oils and solvents
- Can be applied by brush, spray or roller. Traditional varnishes, in comparison, are usually brush applied only.
- Are more durable than traditional wood varnishes.
- Protect wood surfaces – floors, desks, furniture, counter-tops, etc. – for longer than standard wood varnishes, and as such are slightly more expensive than the economically priced counterparts
Polyurethane Varnishes at Rawlins Paints
Keep an eye out for an upcoming article on single and two-pack polyurethane paints and coatings available at Rawlins Paints, from manufacturers including Sikafloor, Teamac, Nullifire and Rust-Oleum.
Blackfriar Heavy Duty Varnish – Water Based
Blackfriar Heavy Duty Varnish is an odourless, two pack water-based polyurethane varnish, primarily designed for wooden floors – but can be used on bar tops, furniture or concrete floors. Delivering a highly durable, non-yellowing and chemically resistant finish, it also resists boiling water, alcohol, coffee, red wine and dilute acid and alkalis.
- Touch dry – 2 hours (20°C)
- Hard dry – 8 hours (20°C)
- Full cure – 3 days (20°C)
- Recoatable after 4 hours
Blackfriar Polyurethane Floor Varnish – Solvent Based
Blackfriar Polyurethane Floor Varnish is primarily designed for use on wooden floors, but can also be used on doors, wood panelling and other joinery applications. For interior use only, it delivers excellent protection against knocks and stains, dilute acids and alkalis.
Available as a gloss or satin, and applicable by brush, roller or spray, Blackfriar Polyurethane Floor Varnish is touch dry in 2-4 hours, and recoatable after 16 hours – under normal conditions.
As with all wood varnishes, ensure that the substrate that is to be varnished is sound and free from any surface contaminant likely to cause adhesion problems – e.g. wax, grease, polish, etc. Always degrease previously wax polished floors prior to sanding and applying the polyurethane varnish.
A great alternative to Blackfriar Polyurethane Floor Varnish is Lacq Floor Varnish X10, a 1K polyurethane, clear, transparent floor sealer based on modified vegetable oil for concrete floors, wood floors, cement floors, porous tiles, garages and kitchens.
Blackfriar Polyurethane Floor VarnishShop Now
Lacq Floor Varnish X10
Blackfriar Polyurethane Varnish – Solvent Based
Blackfriar Polyurethane Varnish is a tough and durable matt, silk or gloss coating that will bring out the natural grain and colours of wooden surfaces. Transforming interior woodwork, with a variety of wood colours and shades available, it offers great protection against common stains, including hot water damage from spills and splashes.
Suitable for all types of interior woods, the matt finish option is not suitable for use on floors, nor should it be used over French polished surfaces.
Please note that the final shade of the applied varnish will depend upon the original colour and absorption of the wood or timber. It is recommended to test for shade on an off-cut or inconspicuous area. When using two tins, it is recommended mixing them, to ensure an even shade is obtained.
The product may be applied by brush or roller. If applying by brush, apply evenly using light strokes following the grain of the wood. If applying by roller, use a short nap mohair roller. For best results 3-4 coats are recommended on new wood and 2-3 coats on previously varnished surfaces. Prior to application of the final coat or if the overcoating time is exceeded lightly abrade with fine glass paper working with the grain and remove dust.
Blackfriar Polyurethane Varnish
Coo-Var P101 2 Pack Polyurethane Varnish
Coo-Var P101 2 Pack Polyurethane Varnish is a clear aliphatic polyurethane coating which provides a hard-wearing protective coating for internal or external wooden floors which regularly undergo heavy foot traffic. It is ideal for gymnasiums, dance floors and performing arts studios.
The product is supplied in two containers: one larger than the other and labelled Base. The other smaller one labelled Hardener. The contents of the pack marked Hardener are added to the contents of the larger pack marked Base and thoroughly mixed together, preferably by slow speed electric mixer for 2 minutes or until thoroughly mixed. Failure to mix the material correctly will lead to uncured areas in the coating.
Coo-Var P101 2 Pack Polyurethane VarnishShop Now
Coo-Var Polyurethane Varnish
Polyurethane varnish is a single pack product of exceptional durability based on urethane alkyd. It is intended for interior use only, on restaurant, café and kitchen worktops, and internal doors.
Available in gloss, matt and eggshell varnish finishes, this clear coating can also be used on smaller floor surface areas.
Coo-Var Polyurethane VarnishShop Now
Rust-Oleum 4900 Polycoat 2K – Water Based
Rust-Oleum 4900 Polycoat 2K is a clear, water-based, 2-component polyurethane topcoat for use on wood, concrete and pre-painted surfaces, also serves as an anti-graffiti coating. Very abrasion resistant, available in a matt or gloss finish, does not yellow, can be used internally and externally, resists boiling water, alcohol, coffee, red wine, dilute acid and alkalis.
- Clear varnish for parquet to protect against stains and scratches
- Clear sealer for concrete to decrease dusting and increase cleanability
- As an anti-graffiti coating
- As a topcoat on previously painted surfaces to provide extra protection and/or change gloss level
Rust-Oleum 4900 Polycoat 2KShop Now
Next Generation Wood Varnishes
Traditional wood varnishes can take a lot of time to apply and lots of preparation before and during application to ensure a brilliant and protective finish. Whilst this may suit woodworkers, others such as consumers and professional applicators are demanding wood finishes that are easier to apply, quicker to dry, and provide excellent protection for wood surfaces.
Advanced, next-generation wood varnishes from Rubio Monocoat provide these much-wanted features and the advantages of wood oils, varnishes, and waxes, over their traditional counterparts:
- User-friendly application
- Fast drying
- Hardwearing protection in just one or two coats
- Long-lasting, durable finishes
- Very easy to maintain
- Require much less preparation to apply more coats later
- Beautiful finish comparable to that of traditional wood varnishes
- Large choice of colours
- Anti-greying and excellent resistance to UV light, dirt, etc
- Wide range of compatible wood species
Rubio Monocoat Varnish 2C
Rubio Monocoat Oil Varnish 2C
Rubio Monocoat Invisible Protector
If you require any further information than that covered in this article, please leave a comment below, or contact Rawlins Paints’ technical support team.
Hi , I’ve been asked by a customer to seal their kitchen table. It is a painted mdf table with several coats of paint and 3 coats of a water based varnish sealer which isn’t durable enough for everyday use. Just looking at the spec of your rust-oleum 4900 polycoat 2k water based finish , do you think this can be applied and have the durability that they’re looking for. Im a decorator and i would make sure that it would be sanded correctly to receive the new finish.
Rust-Oleum 4900 Polycoat 2K would be our best option for your application but please keep in mind that although touch dry fairly quickly, it would need a full 3 days at 20°C for it’s full cure when it can then be exposed to abrasion and liquids.
Hope that helps – certainly come back to us if you need any further information.
Can Estapol be used to cover acrylic paints? If so what sort is best?
I’m afraid we do not sell Estapol products so have no knowledge on their uses and compatibility.
I have been asked to make large bird boxes using 9mm exterior grade ply and need a varnish to seal the edges and coat the face. what would you advise please.
We can recommend Coo-Var Yacht & Seaplane Varnish as a highly-durable finish – the link goes to the product on our store page.
Is this suitable for outdoor decking. The wood will be hardwood, Bangkirai or Kapur and may be used in north and south Europe, so would need to be resistant to hot sun and also heavy rain and frost. There will be metal furniture and stone planters which may need to be moved by dragging. How long will an oil based product last and what is needed workwise when it needs redoing?
Unfortunately we haven’t a product that we could recommend for this application.
I have mahogony window sills that I poorly protected 15 years ago, when originally installed, and are now discolored. By all the UV rays we get in Colorado @ 7,000 ft. And they are a light, bland color.
I would like to:
1) dye/stain them to bring out the grain & give them a more distinct amber/golden (but not dark) color.
2) finish them to make them more resistant to all the UV we get.
Since they are window sills they see little traffic or water, just a ton of UV rays.
Thanks a bunch for your suggestions,
I’m afraid we don’t supply outside of the UK and so I’m unable to provide advice, since products in the US may behave and react differently.
I have a freshly veneered small cabinet that I want to give a clear satin finish to and would prefer to use a water-based polyurethane varnish. I have found that with each coat added the finish looks darker and flatter. I have been recommended to do only the top coat with satin and earlier ones with gloss. But I can’t find a water-based clear varnish that is gloss. They all seem to be satin while the gloss ones all seem to be oil based. Is there a water-based polyurethane clear gloss varnish? It would be helpful if polyurethane varnishes were labelled either water or oil based on the tin but that is not the case or at least it is not
clear from online ads.
Is what I am planning to do possible or am I stuck with using only satin for all coats? If there is such a thing as a water-based clear gloss polyurethane varnish which would be best for me to use?
Sorry to hear of your frustrations – we can offer Coo-Var Acrylic Varnish which has a water based clear, gloss finish, that should suit your requirements.
I have 30 sheets of Birch ply to fix to interior walls and a ceiling in a domestic setting. I want a non yellowing seal to retain the Birch colour. What do you recommend?
Thanks for your question; we recommend Rust-Oleum 4900 Polycoat 2K for this application. All data sheets are on the product page, but if you need any help with application then please feel free to come back to us on here, or contact our technical team directly.
Can you tell me the best varnish ,or is there something better for solid wood flooring Regards Terry Heeney
Thank you very much for your question. The best option we could offer for this application would be Coo-Var P101 2 Pack Polyurethane Varnish but this would not be compatible over a conventional solvent based paint or varnish.
Should you have an existing coating on the floor that is solvent based or if you are unsure what is already applied, please contact our technical team on 0113 245 5450 Option 2 to discuss an alternative option.
I hope that helps, please feel free to get in touch if you have any further questions.
Installing two bar tops inside of a horsebox for conversion into a mobile bar. I want these bar tops to be well protected and long lasting durability, what products would you recommend that I use for this?
Many thanks for getting in touch. Assuming the bar tops are solid wood we would recommend Teamac High Performance Polyurethane Topcoat in either a colour or in clear for this application.
I hope this helps and please feel free to get in touch if you have any further questions.
Looking for the best option to seal a plywood floor in a sauna.
Thank you for getting in touch. For this application we would recommend Teamac High Performance Polyurethane Topcoat in Clear, which can be applied directly to bare timber.
I hope this helps and please feel free to get in touch if you have any further questions.