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There are many advantages to using shellac. Low toxicity, ease of application, and ease of repair are the best reasons to use shellac. Yet, like any finish, there are some disadvantages which are mentioned below. However, some of the reasons people cite as the disadvantages of shellac are based on misconceptions. Two of the most common ones can be easily explained. The first is that it won't dry. This problem can be avoided by using freshly dissolved shellac flakes. The second complaint against shellac is poor moisture resistance. This can be overcome by using de-waxed shellac and fresh product. Using old shellac solution will decrease its moisture resistance. You can easily prove this. Take a board that has been finished with fresh shellac and after it has fully dried (about a week), pour some water on the finish and let it sit overnight. When you come back the next morning you will still see the puddle of water, but the finish will be only slightly marred. Shellacs ability to withstand water decreases with the age of the film, so don't try this on old finishes.

An interesting feature of shellac is that it resists water vapour very well. In tests done by the United States Forest Products Laboratory on the moisture-excluding effectiveness of wood finishes (the ability of a finish to prevent moisture vapour from entering the cellular structure of the wood - called MEE), shellac rated above polyurethane, alkyd and phenolic varnish and cellulose-nitrate based lacquers.

1. Non-yellowing when compared to varnish and cellulose nitrate based lacquers.

2. Quick-drying. Many shellacked items can used the same day or shortly thereafter.

3. Wide variety of colours available.

4. Superior adhesion -- no other type finish can surpass it.

5. Excellent hardness -- it can be sanded and rubbed out well.

6. Excellent as a sealer coat to raise the fibres of the wood for subsequent sanding.

7. Also seals in finishing contaminants such as silicone, waxes, dirt and oils.

8. Ease of repair. Because shellac re-dissolves in alcohol, scratches and other minor surface imperfections can be invisibly repaired by re-applying shellac to the damaged area. The new shellac melts into the old shellac allowing for perfect repair work (see Repairing Shellac article).

9. Ease of removal. Old and new shellac can be removed with denatured alcohol that eliminates the need for harmful and toxic strippers.

10. Can be wiped on (padded), brushed or sprayed -- all with good results.(see Different Applications article)

11. Safe for food utensils and children's toys.

12. No unpleasant or toxic fumes.

1. It re-dissolves in alcohol so perfumes and strong alcoholic beverages like whiskey will mar the surface.

2. Forms white rings on contact with water. This is more of a problem with shellacs that have wax and old shellac surfaces.

3. Tendency to show scratches. The resistance to scratches can be improved by a simple waxing.

4. Has a shelf life after mixed in alcohol.

5. Not resistant to alkaline compounds. Alkaline chemicals such as lye and ammonia discolours and marks shellac because of its acidic composition.

6. These chemicals are frequently found in household cleaning products. Sensitivity to heat -- shellac starts to soften at about 150 degrees F. Hot items can mark the surface.

Keep in mind that some of the disadvantages, like scratching and marking with alkalis, are easily repaired because of one of shellac's great advantages -- Ease of repair.