What are some effective ways of sealing an opened tube of caulk so that the contents do not dry out? In the past I've used a large nail and some tape, but that doesn't seem to last for more than a few weeks.

  • See, modern silicon caulking solidifies when it comes in contact with humidity in the air . If I want to decrease the amount of solidified caulk in the nozzle, I wipe the excess of caulk flush with the tip and wrap the nozzle in aluminum foil as tight as I can, then replace the cap. This is the best seal I can think of.
    – ajeh
    Aug 30, 2017 at 14:57

23 Answers 23


I always leave a blob of caulk on the tip that's large enough for me to grab onto. It dries and seals the rest of the tube. When I'm ready to use the tube again, I just pull it off.

  • 3
    Will this work with all types of caulk? Oct 7, 2015 at 12:28

Plastic wrap (Saran wrap) and an elastic band.

  • 1
    I have used plastic wrap also, works great. for short term storage, the plastic caps in the paint dept of box stores also work pretty good. 2 caps for like $3.00 Jan 14, 2011 at 19:43
  • I usually use black electrical tape (unlike elastic bands, I always have some in my main tool box), and I've had caulk that's lasted for a year that way. If you relieve the pressure and cover it, naturally there will be no air in it and so it stays ready to use.
    – gregmac
    Oct 9, 2012 at 1:52
  • I do this, but with the addition of pumping out some additional caulk/glue so it blobs (so a combination of this and the blob method) After the first use, I reuse the same plastic-wrapped blob if it has not hardened all the way through.
    – Ecnerwal
    Nov 17, 2015 at 22:30

I've always used a drywall screw. It seems to last a few months depending on the type of caulk.

  • I too have used this method. IMO it does not work great but is better than nothing.
    – auujay
    Jan 14, 2011 at 15:12
  • Some will rust in the nozzle and then stain the caulk.
    – Rob
    Oct 8, 2012 at 12:02
  • 1
    Galvanized does pretty good at preventing that, plus the screw can draw the set plug or bore through it if long enough. I've had caulk set despite using the red rubber caps and end up driving a drywall screw in anyway. Oct 8, 2012 at 14:53
  • I use w/e fastener laying in the bottom of my bag that I'm willing to part with. Nail, screw, piece of wire.
    – Mazura
    Feb 5, 2022 at 3:09

The best solution I've found is to fabricate a container out of PVC pipe and two end caps, found at any hardware store. I cut the PVC pipe to about 12", permanently glue one end cap onto the pipe and use the other end cap to seal the pipe without glue. I place a small rubber cap from my junk drawer onto the open/cut tip, spray a small amount of Bloxygen into the PVC pipe, insert the caulk tube and place the second cap onto the pipe. I keep the containers standing upright with the tip facing downward to ensure that the Bloxygen encapsulates the tip instead of any air that might remain inside. This is because Bloxygen is heavier than air. I've also used clear acrylic tubes with caps, which work better because I can see what's inside and they have a flat bottom, which enables them to stand up while stored. It's just hard to buy a small quantity of these since they're sold in bulk. You can find out more about Bloxygen at: http://www.bloxygen.com/ It costs about $11.00 per can plus shipping. Note: I have no connection with, or interest in, Bloxygen other than as an end user of the product.

No, this is not spam. As I mentioned, I am an end user of the product and have no connection whatsoever with Bloxygen. I'm just a guy in the same boat as many in trying to find the best way to save partially used caulk tubes. I came across this product a while ago and have been able to save a lot of expensive paint, adhesives, caulks, etc. I just thought my suggestion might be helpful to someone. If not, just ignore it.


I use screw on electric caps. I always seem to have a few around, and you don't need a screwdriver or drill to get it on the tube. It works well, but like most of these solutions it is only a short term solution, once you open a tube of caulk it has a shelf life and if you don't use it you lose it.

  • 1
    The actual name is "wire nuts" or connectors and is my preferred method. And "lose" is spelled l-o-s-e.
    – Rob
    Oct 8, 2012 at 12:01
  • 2
    @Rob Actually, they are Twist-on wire connectors. "Wire nuts" are Ideal Industries version.
    – Tester101
    Oct 8, 2012 at 16:38

Lee Valley Nozzle Caps or Twist and Seal Stoppers

  • anyone know of a UK supplier? Jan 18, 2011 at 15:38
  • They ship Internationally so I called to see what the estimated cost of shipping 1 unit of each of the above items to London would be. The shipping came in at roughly $9-17USD for UPS so definitely not economical. She couldn't give a better estimate without a full shipping address.
    – CapitalBoo
    Jan 19, 2011 at 19:01
  • Found it on Amazon (for Canada) too: amazon.ca/Little-Red-Cap-Contractor-Saving/dp/B000H5S8XY/… Sep 11, 2020 at 1:49

My dad uses electrical tape. It will eventually fall off, about the same time that the caulk would be useless anyway. Has the advantage that the black tape is easy to spot and is a reminder that the tube has been opened.


I've been using Little Red Caps for the past two years; they're little rubber caps that you roll over the end of a caulk tip, and they seem to make a nice tight seal.

I've used them with drywall glue, construction adhesive, and silicone caulks, and all were easy to use and reuse. I've been using one particular tube of silicone caulk for six months, about once a month, and every time I roll the red cap off, the caulk is as fresh as new.

I used to use a drywall screw, but that method only works for smaller tips, and also can rust closed if there is even a slight imperfection in the seal.


I have used the little red condom caps with satisfactory results. But with a construction adhesive or silicone, which tend to solidify despite the red cap, I would use the "blob method" in conjunction with a long (3" or better) coated deck screw (or zinc bolt) plus a washer. The washer helps give you something to grab on to when removing your screw stopper and any dried material that comes with it. The longer and fatter the screw, the better. A longer, fatter, screw will ensure a channel remains for the good caulk/adhesive to flow out of. All else fails, I start cutting away the nozzle.


I use clear packing tape. Cut a 6-inch section, fold it over the caulk tube tip so the sticky sides face each other, press down and twist. Gives you a good seal and is easy to remove.


Silly putty works wonders. It sticks and shapes into any form and will not harden so removal is easy. 30yrs of construction experience tells me this.

  • I have actually used silly putty it works but gets messy with some types of calking.
    – Ed Beal
    Nov 6, 2017 at 23:35

I use Keokuk Caulk Wax. It seals anything that comes in one of those tubes, adhesive, caulk, silicone, etc., and i've had caulk last for well over a year and a half with out a problem. I have yet to lose an open tube. the other nice thing about it is that you can seal a bunch of tubes all at the same time without having to buy a whole bunch of different caps or plastic plugs. unfortunately you can only get it on line right now, but I think it is around $7 and i have sealed probably 60 open tubes and i still have plenty of wax left in the can.


I tend to use a 3" deck screw. The coating makes it less likely to rust (but I still squeeze out some caulk into the trash until it runs clean). And the 3" is usually long enough to reach the caulk that hasn't dried. The benefit of the screw is that you pull it straight out with a pair of pliers and it will take any dried caulk out with it. If there's too much dried caulk to pull it straight out, I'll often cut the tip larger.


I prefer a hot-dip-galvanized 16d common nail; something in the zinc seems to slow down curing a little. If the caulk still dries in the tube, I curse myself for being so all-fired cheap and go buy another tube - each tube costs less than a pack of cigarettes, a gallon of gasoline, or a cheap meal.


I found a pretty good product at Menards called Seal-A-Tube made by Core Gear. It's a plastic cap with a long plastic pin inside of it that goes into the caulk hole that you've cut open. They cost less than $2 each. I tried one out and liked it so much I bought about 5 more. So far, every tube I've taken this cap off of was ready to go again and not dried out.

Seal-A-Tube made by Core Gear Product Page


A blob of your kid's modeling clay works great. It will hold up for the long term, too. Make sure you use the oily reusable modeling type of clay that never gets hard. Roll a three-quarter-inch ball, stick it over the hole, then pinch it around the top of the nozzle to seal off the air.


A wooden golf tee sealed with electrical tape. Have had opened caulk last for multiple years opening multiple times along the way. Use the shorter version or snip off to about 1 inch. Stick the tee in and then 2 pcs of tape pulling down the tee to seal it. Then wrap tape around the tape you just added so that it holds it in place.


I double wrap Handi-Wrap around the nozzle and secure it with a rubber band. (Tape would work well, too.) Then I place the tube in a gallon freezer bag, roll the air from it, and seal it. This is a quick fix to a cheap problem.


A small blob of epoxy putty stuck into the end. when it's time to use again just cut of a little more of your tube end.


Went to Menards and got the plastic tube sealer with the long plastic stick in the middle for $1.99 each.if your caulk is quite old and hard inside the tube I micro-wave the tube for about .25 seconds making sure there is NO metal on or inside the tube and remove any left over caulk in the tip. Works like a charm.


After each use I use a wooden skewer to remove as much as I can from the inside of the tip, then I light a candle and pour liquid wax to seal until next use. Then I top it with a wire nut.


I supposed one could seal it easily with some polycaprolactone. It's a thermoreversible hard plastic which remelts to a clear putty like state when dipped in boiling water for a minute. It can be reused over and over and when cooled back down returns to hard white plastic. it bonds extremely well to other plastics like the plastic used for the nozzle of caulk tube, would definitely seal it off probably as good as a new tube is sealed off. I have some and came across this and just though about it and will try it just thought I'd pass it on. Also if it won't be used for more than a few months consider also sealing the bottom, most caulk rubbers cure by moisture in the air (humidity) finding its way in and doing the irreversible crosslinking. and the bottom plunger does not seal it off perfectly otherwise it wouldn't slide.

I just tried it with a new tube of clear silicone sealant. It made a decent form fitted cap/plug from PCL but when twisting it came off making it a releasing cap/plug for me, good enough for short term. Adhesives are usually made from polyproyplene PP since most things do not bond to it apparently not even PCL, although pcl bonds much better to wood, metal, and pvc. I use cheap polyethyelene gloves when handling pcl and or jersey gloves with poly gloves overtop because it sticks to vinyl and nitrle gloves probably would latex too. A hot glue stick designed to bond to PP may be another option.

I just read someones report that shoe goo sticks to polyproyplene. I have a tube of E6000 got at dollar general which according to all the specs having read it last month is the generic equivilent of shoe goo and amazing goop. All 3 having the same shore hardness, elongation percentage at break and available in clear, and all featuring proprietary polymer as the main constituent but unpublished. worth a shot for long term. Hypothesis that even with perfect seal top and bottom the initial air introduction will entrap moisture rendering viability less than a year >90% of cases.

  • Concerning sealing of the bottom plunger: it's a problem that has always been felt a lot. Already in the '80s: google.com/patents/US4217995 I hope they found a way nowadays to do it properly.
    – FarO
    Nov 18, 2015 at 14:24

I typically let it dry, there is no way to stop it. After it does and I need it, I carefully split the nozzle with a razor knife, pry open the end and pull out the cured tip. I use tape to repair the slice I made and carry on with the tube.

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