A method for making an environmental barrier coating using a sintering aid comprising: applying a bond coat layer to a ceramic component; combining at least water, a primary transition material comprising a rare earth disilicate, or a doped rare earth disilicate to produce a transition layer slurry; combining at least water, and a primary outer material comprising a rare earth monosilicate or a doped rare earth monosilicate to produce an outer layer slurry; combining at least water, and a primary compliant material comprising BSAS or a rare earth doped BSAS to produce a compliant layer slurry; applying at least the transition layer slurry, and any one or more of the outer layer slurry, and the compliant layer slurry; and sintering the component to produce the environmental barrier coating having at least the bond coat layer, a transition layer and any of an outer layer or a compliant layer wherein at least one of the transition layer, the outer layer, or the compliant layer further comprises at least one slurry sintering aid and wherein a reaction between the primary materials and the slurry sintering aid results in the transition layer comprising a porosity of from 0% to 15% by volume of the transition layer, the outer layer comprising a porosity of from 0% to 30% by volume of the outer layer, and the compliant layer comprising a porosity of from 0% to 30% by volume of the compliant layer wherein the slurry sintering aid is selected from the group consisting of iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, gallium oxalate, aluminum oxalate, nickel oxalate, titanium oxalate, water soluble iron salts, water soluble gallium salts, water soluble aluminum salts, water soluble nickel salts, water soluble titanium salts, water soluble boron salts, and water soluble alkaline earth salts. applying a bond coat layer to a ceramic component; combining at least water, a primary transition material comprising a rare earth disilicate, or a doped rare earth disilicate to produce a transition layer slurry; combining at least water, and a primary outer material comprising a rare earth monosilicate or a doped rare earth monosilicate to produce an outer layer slurry; combining at least water, and a primary compliant material comprising BSAS or a rare earth doped BSAS to produce a compliant layer slurry; applying at least the transition layer slurry, and any one or more of the outer layer slurry, and the compliant layer slurry; and sintering the component to produce the environmental barrier coating having at least the bond coat layer, a transition layer and any of an outer layer or a compliant layer wherein at least one of the transition layer, the outer layer, or the compliant layer further comprises at least one slurry sintering aid and wherein a reaction between the primary materials and the slurry sintering aid results in the transition layer comprising a porosity of from 0% to 15% by volume of the transition layer, the outer layer comprising a porosity of from 0% to 30% by volume of the outer layer, and the compliant layer comprising a porosity of from 0% to 30% by volume of the compliant layer wherein the slurry sintering aid is selected from the group consisting of iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, gallium oxalate, aluminum oxalate, nickel oxalate, titanium oxalate, water soluble iron salts, water soluble gallium salts, water soluble aluminum salts, water soluble nickel salts, water soluble titanium salts, water soluble boron salts, and water soluble alkaline earth salts.