Frequently Asked Questions
We can never cover every possible question or circumstance, so be sure to contact firstname.lastname@example.org if you have any questions you can’t find the answer to here. But here are some frequently asked questions, as well as other real questions, we have received.
Use a screwdriver or similar tool to pry up the friction cap. Work around the cap lifting it a little each time. When finished, tap the cap firmly back into place to keep the powder dry and ready to use.
Durham’s® is not intended for use in high temp areas. Especially not in fireplace repairs and the like where flames or heat is high enough to start a fire. It doesn’t burn, but it will break down and crack after such exposure.
Durham’s does not respond well to any flexing and stretching and will not adhere in such patches. Consider an epoxy or silicone repair material for this kind of application.
Durham’s is not waterproof, nor should it ever be used for structural, or load-bearing, application. Consider a concrete-based patching material or hydraulic cement stop-leak material for pinhole-sized water leaks.
Removing Durham’s can be difficult, but if you get it wet and let it absorb some moisture, it may help in getting it out. You will need to break it up or dig it out. If it’s not too thick, you may sand it out. It needs to be removed by mechanical means. We have had pretty good luck drilling down through the middle of the patch and putting a screw or nail in to break the putty loose or into smaller pieces.
Yes. Durham’s is often used for this. It can be spread over the underlying materials and textured using a piece of damp terrycloth, sponge, or other rough material. You can add more putty if needed, or embed stones to simulate a rocky outcropping. You can also help anchor the putty by putting some screws into the wood with the heads sticking up and spread the putty around them, if you want. But that’s only necessary if the item is going to get some rough handling.
Durham’s Water Putty does not expire, you just need to be sure that it is kept dry and sealed in its can. A very old can may lose some strength, but will still mix up fine and should be useable for most repairs. If it has hard chunks, discard it, because that means it has gotten damp.
Since putty can be fluffy or packed in a can, the important thing is to mix it by weight. About three parts putty to one part water. If it is difficult to weigh it, then be sure to “pack” the powder in the measuring container. You can just put some powder in a container and add the water a little at a time, and keep stirring until you reach the consistency you need. You can make it thicker to avoid sagging in vertical applications. Or much thinner if you are casting a figurine. A thicker mix on a hot, dry day gives you a shorter working time. But other than that, putty is quite flexible and forgiving.
None of the ingredients are toxic or harmful to humans. Nor have we heard of Durham’s causing problems for dogs, cats, or other animals. The ingredients of water putty are mostly minerials, like limestone, and a plant-based starch binder. There are no volitile organic compounds in Durham’s.
For deep holes we recommend putting in about a quarter inch of putty at a time and letting it dry overnight between applications.
No, the putty is hard and brittle and will crack. We usually drill through the Durham’s and then nail into the wood beneath the patch.
No. Using stain instead of water adds a lot of other ingredients that will not harden or be durable.
Durham’s has been used for this purpose for many years. It expands slightly as it sets up, so be sure it is level by checking it frequently as it sets up and by scraping off any excess with a wide-bladed putty knife. If your patch is a little underfilled just add some more putty, as Durham’s sticks well to itself.
Yes. Durham’s can be colored by adding a water-based coloring agent to the putty when mixed. Use black to create gray colors. Use a dry powder pigment that you might find at an art supply store.
Durham’s can be used outdoors, but keep these things in mind…
Durham’s can be used outdoors and will withstand outdoor weather, but it must be kept painted. Water putty is not waterproof and will absorb any moisture it is exposed to and the paint will peel. So if you see peeling, you must find the source of the moisture and stop it from gettting into the putty. Durham’s also must not be used in structural, or weight-bearing, applications.
Durham’s does not absorb a stain, so the patch must be painted and not stained.
Durham’s is intended to be applied in actual voids or cavities and should not be applied in a layer over the face of a board, since it can come loose with the slight expansion of the underlying surface.
Durham’s is not recommended for porch floor or deck repairs or other areas that are difficult to keep sealed from moisture.
If paint peels from the putty, it is either not thoroughly dried and has a high moisture content, or it is getting damp or absorbing moisture from some source.
If the area that you are filling is deeper than about 1/4 inch, you should fill in layers of about 1/4 inch and let the putty dry overnight before applying the next layer. On deep fills that are done all at one time, the water putty at the bottom of the fill will remain quite damp for many days, since all the moisture that is deep in the patch has to work its way through the dried putty that is exposed to the air.
If you cannot discover how a patch is getting damp, and paint continues to peel from it, sometimes the patch can be sealed using a thin coating of clear glue suitable for indoor/outdoor use, shellac, or an exterior polyurethane, and then painting over that.
No, you should not use Durham’s on deck or porch floors. Durham’s is not waterproof and will absorb moisture from between boards and underneath the deck or porch. Durham’s can crack or break loose when the floor flexes and it must not be used in structural, or weight-bearing, applications.
No. Durham’s can be used outdoors in applications protected from moisture, but it is not waterproof and would absorb moisture from the backside or the ground in this application. There are other products made for this purpose that would work better.
Durham’s is not intended to be a cure for leaking concrete foundations or other leakage problems, as it is not waterproof. Check with your local home center, lumber, or hardare store for a product intended for use on leaking basement walls, cracks in concrete pools, or fountains where there is constant hydraulic pressure. Durham’s can be used on concrete, but is intended for cosmetic repairs, not structural or repairs where it would get damp.
Sometimes it can be hard to judge how much putty you need for projects. A 1 Lbs can of Durham’s will make about 1-1/2 cups of putty (or 21 cubic inches) when water is added. 3 Lbs of product will make 63 cubic inches. 82 Lbs would make 1 cubic foot.
To put that into perspective, 100 lbs of water putty covers 60 square feet at ¼” thick.