How do I store glue, sealant and filler so they are still usable next time?

Almost every part-used tube in a British shed is dead, and the reason is usually storage rather than age. The failure mechanism differs completely between products: water-based adhesives are destroyed by freezing, moisture-curing ones cure inside their own container, solvent-based ones thicken as the solvent escapes, and everything degrades faster warm.

Safety

Step by step

1. Keep everything above freezing.PVA, water-based grab adhesive, acrylic caulk and ready-mixed filler are emulsions, and freezing breaks the emulsion permanently. A product that has frozen and thawed goes grainy or curdled and will never recover, however normal it looks after stirring. An unheated shed in a British winter is not a safe store for any of them.
2. Keep everything cool and out of the sun.Heat shortens shelf life across the board and it is the main reason a product bought a year ago is unusable. A cupboard inside the house is far better than a garage for the products that matter.
3. Squeeze the air out of moisture-curing products.Polyurethane glue and superglue cure by reacting with moisture in the air, which means the air trapped in the bottle is slowly curing them. Squeeze the bottle to expel air before capping, and cap hard.
4. Store superglue cool, dry and sealed.In a small sealed bag or airtight tub, in a cool place. A fridge genuinely extends its life provided it is sealed against humidity, and it must be brought back to room temperature before opening or condensation will cure the nozzle shut.
5. Wipe the thread and the nozzle before capping anything.Product left on the thread cures and welds the cap on. Ten seconds with a rag is the difference between a bottle you can open next time and one you cannot.
6. Seal cartridges properly and stand them nozzle-up.A tapered plug, a proper cartridge cap, or a long screw pushed into the nozzle. Standing them upright stops the contents settling into the nozzle and stops a slow leak emptying itself onto the shelf.
7. Keep ready-mixed filler airtight and level.Press the surface flat, wipe the rim clean so the lid seats, and press the lid fully home. A skin forming is normal; the tub is finished when the material under the skin has stiffened.
8. Keep powder filler and powder adhesive genuinely dry.They absorb moisture from the air and go lumpy, and a lumpy powder filler will not mix smoothly or set properly. An airtight tub or a resealable bag inside the paper sack.
9. Date the container when you open it.A marker pen and the month. Shelf life is quoted from manufacture and the date code is often unreadable, so your own opening date is the more useful number.

Tips

• Buy the smallest size that will do the job for anything you use rarely. A part-used tube of sealant is worth very little once it has been open a few months, and the small tube usually costs less than the waste from a large one.
• A cartridge nozzle with a solid plug of cured sealant in it can often be recovered: cut the nozzle back behind the plug, or pull the plug out with a screw and pliers.
• Two-part epoxies keep well because neither part cures on its own, but the hardener yellows and can crystallise in the cold. Warming the tube gently usually restores it.
• Never mix an old and a new tube of the same product. If the old one is marginal it will simply spoil the batch.
• Store solvent-based products upright and in a ventilated place. A cupboard that smells strongly of solvent has a leaking container in it.

Common mistakes

• Leaving water-based products in an unheated garage over winter — One hard frost destroys them permanently. This is the single largest cause of wasted adhesive and filler in a British home.
• Storing a cartridge with a nail through the nozzle — It works for a day or two and then the air gets past. Use a proper cap or a tapered plug pushed well in.
• Keeping superglue in a warm kitchen drawer — Warmth and humidity are exactly what shortens its life. Cool, dry and sealed is worth several months.
• Topping up a tub of filler with water to soften it — It changes the mix, weakens the set and usually makes it shrink more. Once ready-mixed filler has stiffened, it is finished.

Keeping on top of it

• Check the store for anything that has frozen or gone solid, and dispose of it (each spring)
• Turn cartridges nozzle-up and check the seals (when tidying the store)
• Bin part-used solvent cement and superglue that has thickened (annually)

Questions people ask