What Is PVA Glue?

I don’t mind admitting it. I love glue. I have at least six different kinds in the cupboard at any one time, and PVA is a can’t-do-without staple. I’ve used it for all manner of creative, practical and DIY projects. It’s low cost, safe, easy to use and incredibly handy. But what is PVA’s secret? What lies behind this seemingly simple product that makes it such a useful piece of your wood finishes kit… what is PVA glue?

Barrettine-Pva-Adhesive-Sealer

PVA Glue / Adhesive and Sealer from Barrettine

What is PVA?

What is PVA glue made from? Our first stop is Wikipedia. Here’s what it says about PVA:

“PVA is a rubbery synthetic polymer with the formula (C4H6O2)n. It belongs to the polyvinyl esters family with the general formula [RCOOCHCH2]. It is a type of thermoplastic. Polyvinyl acetate is a component of a widely used glue type, commonly referred to as wood glue, white glue, carpenter’s glue, school glue, Elmer’s glue (in the US), or PVA glue.”

PVA glue facts

Polyvinyl acetate, PVA’s main chemical component, was discovered by the German Fritz Klatte in 1912. The resulting glue doesn’t give off smells or dangerous fumes and is perfectly safe to handle with bare hands.

As well as ‘real’ wood you can use it on plywoods, chipboards and MDFs. It can be used as a high performance sealer, primer, bonding agent and dust proofer.

PVA sets when there’s good air circulation, and dries fastest at room temperature. You get the strongest seal when you clamp the pieces being glued. It’s quick drying with a very high bond strength.

The yellow exterior version of PVA is often called Carpenter’s Glue… but it’s still PVA. In fact there  is a bewildering array of specialist PVAs but the formula is much the same.

PVA is flexible, permanent and only toxic if you eat it. It has a neutral PH.

PVA is water soluble. You can add water to thick glue yourself to create a thinner, less gloopy one. It’s best to add water to the glue (not the other way around) a small amount at a time and stir it well, to make sure you don’t over-dilute.

Here’s what Woodwork Basics says about PVA:

“This glue is now very popular and in many opinions it is the best timber adhesive available because it dries clear, it’s very easy to apply and has super strong holding strength on wood.

They can creep over time but a tight joint helps to prevent that. Because of its many great features Polyvinyl Acetate is excellent for bonding woodwork joints together or as a furniture and carpentry adhesive.

Polyvinyl Acetates are very versatile and are relatively fast drying but excess glue must be wiped away after applying or it is very difficult to remove when dry.

Polyvinyl Acetate glues are available in white and yellow and are relatively inexpensive compared to most glue, they also have a reasonably long shelf life.

The white one is better for interior use because moisture weakens it over time and the yellow is better for outdoor use because it is water resistant but it doesn’t dry completely clear.”

And here’s what the Woodworkers Institute says about PVA:

“Most woodworkers today use the white wood glue, PVA. This provides a strong, and as far as we know, durable joint. The only glues that have really been tested by time are the animal glues and natural resins and gums. These are likely to be affected by heat and damp, and the animal glues, being rich in protein, are an invitation to insects and moulds if there is moisture present. Although some PVA glues are advertised as suitable for outdoor use, it is best to use a formaldehyde resorcin.

One possible drawback with PVA is that if you are gluing oak (Quercus robur), it may react with the tannin in the wood and go black, even staining surrounding wood if the surplus is not wiped off immediately.”

Plus, here’s a Youtube video about applying PVA glue.

PVA glue uses

What is PVA glue used for? As an emulsion, soluble in water, it is particularly useful for glueing porous materials, particularly for wood, paper and cloth. It doesn’t contain solvents and acts as a useful consolidant for porous building materials like sandstone. PVA adhesive is flexible, delivers a very strong bond and, unlike many polymers, it is not acidic. PVA wood glue is most often used:

  • as a wood adhesive
  • as a paper, fabric and leather adhesive
  • in bookbinding
  • in arts and crafts,  for example mosaic
  • as envelope adhesive
  • as wallpaper glue
  • as a drywall primer
  • as a filler, by adding sawdust to it

A mixture of 50/50 PVA and water makes a very good sealant for plaster, preparing it for painting or wallpapering. It can also be used as a non-waterproof interior varnish, perfect for papier mache projects.

7 steps to using PVA to glue wood

PVA is a low cost, water based, non-toxic way to glue wood to itself. Wood glue is a particularly strong version of ordinary PVA, ideal for heavier jobs. It dries completely clear but you can also buy pre-coloured versions that are less visible on wood surfaces.

  1. Squeeze the glue onto the surface of both of the bits of wood you want to glue together
  2. Remove any excess or spills immediately using a damp cloth
  3. Use either a specialist plastic spreader or a brush to spread a thin coat of glue over the surface of both pieces of wood
  4. Push the pieces together, rubbing the surfaces from side to side to remove trapped air and make sure the glue spreads evenly
  5. Grab a G-clamp or two and clamp the pieces securely
  6. Leave it for 24 hours before taking the clamps off
  7. Sand off any dried excess glue

The disadvantages of PVA glue

  • Various fungi, algae, yeasts, lichens and bacteria can break down and degrade polyvinyl acetate
  • PVA shouldn’t be allowed to freeze because it breaks up the polymer, which makes the glue useless
  • You can’t varnish over PVA…but you can paint over it
  • It takes 24 hours for the bond to achieve full strength
  • It is not fully waterproof

How to remove PVA?

To get PVA off wood, sand it. If you get it on your clothes, a couple of warm washes should remove it.  If it gets on your carpet, scrub it with warm water then Vax it up.

The most impressive PVA story on the planet?

I used PVA to varnish a decorated ceramic bowl, which I embellished with coloured papers and fabrics. It has been out in the garden for eight years through some of the worst winters and hottest summers on record, and it is still going strong. The surface goes a little milky in wet weather as the glue absorbs water and turns back into something sticky, but that’s about it. So while it isn’t supposed to be frost or water proof, under some circumstances PVA seems to be more or less indestructible.

Do you have a thrilling PVA tale to tell? If so we’d love to hear it!

Want to buy extra strong PVA?

Here are a couple of links to our Morrells Probond PVA Adhesive page and Barrettine PVA Adhesive and Sealer which also contain all sorts of useful information about applying and using PVA Glue products.

 

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42 Responses to “What Is PVA Glue?”

  1. Will Taylor Says:

    I prefer to use the Loctite brand of pva as it cures quicker than other brands I have tried. Usually after half an hour the clamps can be removed. Among other uses, I use it for attaching model clay to foamboard for textured architectural models. The only golden rule here is to also apply the adhesive to the reverse side of the foamboard. This is necessary to equalise the tension created by drying and subsequently slight shrinkage. As a modelmaker, I have to work very quickly so the bulk of adhesives I use are those that bond in seconds rather than minutes or hours but it’s horses for courses. We’re certainly a lot further down the road from my dad’s old glue-pot which sat on a primus stove to keep it liquid. The stench of these old glues however was easily matched by the corresponding bonding power. Many a piece of old furniture stand testament to this.

  2. Keith Says:

    i have used PVA glue as a clear filler on a timber bench, but it hasnt dried clear, after 24hrs it has set, but it is white..???

  3. nick Says:

    Hi Keith,

    Would i be right in assuming that you are looking for a ‘clear’ filler? Unfortunately, i’m not aware of any wood fillers that are perfectly clear. Even fillers that have a name like ‘Natural’ tend to have some sort of colour be it Grey or Beige. If you’re looking to make a repair as less visible as possible, consider something like Fiddes Wood Filler Gel. This is a clear filler that is mixed with sanding dust to make a filler that blends in with the surounding wood. Using sanding dust from the wood being filled will always give the best result. The filled area can then be sanded and if required stained and finished with a varnish or wood oil.

    Always do a test area first.

  4. Linda Says:

    I want to shappy chic a cabinet and someone suggested using this glue first before applying cream paint to it, as it is mahogany at the moment and they said it would help stop the brown coming through.

  5. Sam Taylor-Casey Says:

    Hello Linda,

    I have not heard of this before, so I couldn’t give you a definitive answer I’m afraid. But I do know that Chalk paint covers pretty much everything, so it may be worth trying that. The other option is to use a good primer first and then the paint.

    If you do use a Chalk Paint then you will need to seal it with a Wax Using a coloured Wax can help to achieve the distressed or shabby chic effect that you want. I hope that helps and we would love to see your finished project !

  6. Pete Says:

    Thanks for the info.

    You say, “PVA shouldn’t be allowed to freeze because it breaks up the polymer, which makes the glue useless.”

    I assume you’re talking there about its storage BEFORE use. To be sure though, I’d be very grateful if you would let me know roughly in what temperature range it performs its function as a glue AFTER it is set, assuming it were fully set at room temperature, say. In particular, what concerns me is whether it will hold in a wood joint at a temperature as low as -5C.

  7. Sam Taylor-Casey Says:

    Hello Pete,

    Thank you for your inquiry, PVA should be stored between 5c and 30c. Once it is fully cured it will hold fine at temperatures to -5c, however the temperature change may have an effect on the wood causing it to expand or retract and this in turn could loosen the joints – Sam

  8. Pete Says:

    Thank you, Sam. That’s what I wanted to hear! 🙂

  9. Ella Berthoud Says:

    Dear Sam,
    I need to prime a piece of wood to paint with acrylic paints, then varnish so it can be outside for several years. Will this work with PVA?
    Thankyou!
    Ella

  10. Sam Taylor-Casey Says:

    Hello Ella,

    Yes the PVA would be fine to use as a Primer for the paint and then Manns Extra Tough Interior Varnish as a top coat finish. Always do a test area first to ensure compatibility and adhesion. Please let me know if you have any further questions – Sam.

  11. Doug Says:

    Can PVA glue be used to attach a piece of 3/4″ plywood (10″x 20″) to ABS canoe hull? A block will be mechanically fastened to this plywood for anchoring a sailing mast.
    Thanks,
    Doug

  12. Sam Taylor-Casey Says:

    Hi Doug,

    I am sorry but this is not something I can answer. You may be better finding a forum specific to boat making and maintenance as they will have much more knowledge on a question such as this. I am sorry I could not be of more help.

    Kind regards Sam.

  13. Janet Evans Says:

    PVA clue, I need to know as a teacher doing a bird project/craft whereby we are sticking birdseed on to a board with pva as the base to hold the seeds on. can you confirm that this is a safe product a customer enquired about this and I need to know.

  14. Sam Taylor-Casey Says:

    Hello Janet,

    Apologies for the delay in getting back to you, if you would like to email this inquiry to wood@finishes.direct and I can send you the Safety Data sheets if it is about a product that you are purchasing from us.

    Kind regards Sam.

  15. Annie Says:

    Thanks for this – I needed to know if I could varnish over PVA and you have answered my question. I feel a little more confident now, but could still do with some more info.. I have decoupaged some drawers using wallpaper, for my daughter’s room. I have been putting thin layers of PVA (1 part glue to 5 parts water) over the paper, because I thought these would act as a varnish – however, I’m not sure how much difference it is making, and after my daughter peeled off some drying glue this morning (I nearly cried), I am worried that the finish will not be hardy enough.. Will it harden as it dries fully, enough to withstand regular use, and how many layers should I apply? Many thanks for any advice!

  16. Sam Taylor-Casey Says:

    Hi Annie,

    It sound like a lovely project, and one that you really want to protect so varnish will be the best option. Manns Extra Tough Interior Varnish is the one I would recommend and it will be perfect to use over the the PVA that you have applied so far. Always do a test area first and please be aware that this product is usually for application to wood directly, so although I can not for see any problems, there are no guarantees. Please feel free to ask any other questions and I would love to see the finished result. You can send photos to wood@finishes.direct if you would like.

    All the Best Sam.

  17. Bob Says:

    Looking to spray a troublesome area of peeling decking. Could I use PVA mixed with decking paint for extra adhesion?

  18. Sam Taylor-Casey Says:

    Hello Bob,

    This is not some thing that I can recommend. For surfaces that are peeling and flaking we would recommend stripping back to bare wood and starting again or alternatively if this is not an option then you could sand the affected areas and repaint with the same product. Please let me know if you have any further questions or feel free to call and speak to one of our advisers on 0800 7818 123 – All The Best Ben.

  19. CLARE Says:

    Hi there. i have some wood panelling on the ceiling near my stairs , it has a coat of varnish on it, i have decided to paint it white, dont really want to spend hours or lots of money as its rented accomodation. but still want it to look nice and brighten up the stairs , so i dont have to apply lots of coats , can i PVA it before painting it with dulux eggshell (for wood /metal)matt paint . any help or tips would be great. thanks so much.

  20. Sam Taylor-Casey Says:

    Hello Clare,

    Apologies for the delay, we have made some enquiries to ensure we advise correctly… In short painting over the top of your varnished wood is not the ideal way to ensure longevity.

    Priming with PVA is a popular solution for achieving the ‘shabby chic’ look. This is because some of the paint can come away without detracting from the look.

    However in your instance you want a clean look so the advice is to sand and then prime and paint. It sounds like you would rather avoid sanding so the next best option is to use Zinsser B-I-N Primer prior to the Dulux emulsion. It’s important to note that this won’t give you a perfect result but will be a quick fix that will certainly look satisfactory, especially on a ceiling that can’t be inspected too closely.

    We don’t yet sell Zinsser so here is a link to the recommended product from Screwfix: http://www.screwfix.com/…/zinsser-b-i-n-shellac…/29661 Best Wishes.

    I hope that helps and please feel free to let me know if you have any further questions.

    kind regards Sam.

  21. Aimee Says:

    I want to cover the top of s coffe table in pennies. Can I cover in pva to set them? Will it dry hard enough?

  22. Sam Taylor-Casey Says:

    Hello Aimee,

    Sorry but I can’t help with this one as I really do not know what would be the best glue/ sealer to use for a project like this. I do know that there are lots of examples on Pinterest that have come from Blogs and so you may be able to get some answers from there.

    https://uk.pinterest.com/search/pins/?q=penny%20floors&rs=typed&0=penny%7Ctyped&1=floors%7Ctyped

    All the Best Sam.

  23. Joe Brooks Says:

    I’ve used pva to clean vinyl records, spread fin over record and when it’s dry peel off and brings out dirt from the grooves.

  24. Sam Taylor-Casey Says:

    Great Tip Joe ! Thanks.

    We recommend always trying a small test area first however 🙂

  25. Nancy Kempf Says:

    Good morning,I have seen a number of youtube videos on decoupage paper napkins on wood using white PVC glue.Would you please recommend a white PVC for me to use for this project,and should I mix it half glue and half water.

    Thank you……Nancy

  26. Sam Taylor-Casey Says:

    Hello Nancy,

    We do not specialise in craft glues but the Barrettine PVA Adhesive is likely to be suitable for your project. A test area should be done first. And if there is anything further that I can help with please do let me know.

    All the Best Sam.

  27. Joseph Says:

    Hi,
    I am gluing a large piece of coutertop directly on a chest of drawers, in order to create a kitchen island.

    The countertop is particleboard.
    The chest of drawers is made of Particleboard with an Oak veneer and Clear acrylic lacquer.

    Would PVA glue hold the coutertop in place, even with people leaning on teh counter, which extends past the edges of the drawers? Would I need to remove the lacquer first? Or the laquer & veneer in ordert to glue to the particleboards underneath?

    Thanks for your help.

    Thanks
    Joseph

  28. Sam Says:

    Hello Joseph,

    The surfaces that are to be glued together will need to be free of any finishing products, so the lacquer that you currently have on the draws will need to be removed. Then you could have a look at the PVA Adhesive from Morrells. Which is suitable for many woods including chipboard, MDF and Plywood. Its a versatile, low odour product that could be ideal for your project. If you read up on the adhesive and feel free to let me know if you have any further questions.

    Kind Regards Samantha

  29. Joseph Says:

    Hi Samantha- thanks for your input, I appreciate your time. We went ahead and glued it before seeing your response and it seems to be holding. We did not remove the lacquer before doing so- but only one face had lacquer, the other face was free of any finish so I am sure that helped. I will put a few screws through to give it more stability but at the moment it looks good.
    Thanks

  30. Joseph Says:

    oh- and the glue we used was PVA- similiar to the one in your link.
    Thanks

  31. Maitrey Soneji Says:

    Hii Dear
    My query is on the what is the difference between PVA and water based glue? How water based glue is better than PVA???

    Waiting for your kind response

  32. Sam Says:

    Hello Maitrey,

    Glues are not my field of expertise, I am afraid and so I have referred to Googles endless knowledge to answer your question. Water-Based Adhesives. Water-based (or more commonly referred to as waterborne) adhesives are typically formulated from either: Natural Polymers – from vegetable sources (e.g. dextrins, starches), protein sources (e.g. casein, blood, fish, soybean, milk albumen), and animal (e.g. hides, bones), or.

    And PVA It is a type of thermoplastic. Polyvinyl acetate is a component of a widely used glue type, commonly referred to as wood glue, white glue, carpenter’s glue, school glue, Elmer’s glue (in the US), or PVA glue.”

    As to which is the best, I suspect that it may depend on your project and the type of materials you are using. I am sorry that I can not be of more help but for any wood finishing questions please feel free to come back to me.

    All the Best Samantha.

  33. Maitrey Soneji Says:

    Thanks a lot sam

  34. Tim Parry Says:

    Hi I have a kitchen with floorboards about 150 years old. I want to fill the gaps between the floorboards before painting the floorboards with a water based acrylic floor paint. The gaps are mainly 3 – 5mm wide with some greater and some lesser gaps and mainly 10mm deep. Flexibility of the filler is important to accommodate movement of the floorboards due to usage and changing temperature/humidity. I’ve seen a suggestion that the filler can be a mixture of sawdust and pva. I’ve experimented by inserting some of the mixture into a length of gap using a refilled 310ml decorators caulk tube. However I am told that the pva/sawdust mix will go brittle over time and work out of the gaps. Is this true? Is there a particular type of pva that I could use to maximise flexibility and durability? I would appreciate anyone’s help on this. Thanks Tim

  35. Sam Says:

    Hello Tim,

    We have an ideal product for filling between floor boards Bona Gap Master is a flexible filler that is applied using a Mastic gun. It would be more suited to your project than a PVA and sawdust mix and is easy to use. If you have a read up of the product and feel free to let me know if you have any questions.

    Kind Regards Samantha.

  36. Frances Says:

    Hi, I’m wanting to decoupage a table which I want to be hard wearing. If I glue the paper on with PVC glue will i be able to varnish over the top of it? Thank you for your help.

  37. Sam Says:

    Hello Frances,

    Generally a good quality varnish will be suitable for use over a decoupaged item. It will certainly improve the durability and protection to the surface, it will not be as tough however than if it was applied directly to wood. And I would strongly recommend a test area first.

    I hope that helps and if you have any further questions or wish to share your project you can email me at wood@finishes.direct

    All the Best Samantha.

  38. Deborah Says:

    I am looking for a glue to fix pieces of bark to a picture frame. The pieces are obviously not flat and so I imagine a fairly thick layer of glue will be required. I am also reluctant to clamp it as this may crack the bark and spoil the finished work. Is PVA the right glue to choose?

  39. Samantha Taylor Says:

    Good Afternoon Deborah,

    You could have a look at the Morrells Probond Glue its an expanding adhesive that could be ideal for your project. Always try a test area first and if you have any further questions please do let me know.

    Kind regards Samantha.

  40. Marty Says:

    Hey Sam, thanks for a very informative article, am building a shed out of wbp plywood and cladding it with spaced out softwood timber uprights, wondering if I can use pva to seal the edges of the plywood and also I am considering using it for fixing the uprights to the plywood, are these options viable and can I paint over it if I use pva elsewhere as a sealer?….cheers.

  41. Samantha Taylor Says:

    Hello Marty,

    PVA is a great and versatile product, its uses are not only adhesion based but also great for sealing substrates and using as a primer. It would be suitable for your projects as long as it will not be exposed to frost or freezing temperatures. It can be painted over and in some cases varnished, but it is always strongly recommended to try a test area first to ensure compatibility with any top coat product.

    I hope that helps and if you have any further questions I am happy to help.

    Kind regards Samantha.

  42. Marty Says:

    Many thanks….will use it giving consideration to your reply.

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