Epoxy Resin Sinks – Undermounts vs. Drop-Ins


Epoxy resin undermount sinks, along with epoxy resin countertops, began being manufactured and installed in laboratories in the early 1970's. The chemical-resistance, heat-resistance and structural durability of the material eventually made it the leading choice for labs and the epoxy resin worksurface industry saw tremendous growth. As the product became more popular and widely used, the architectural and design community began to focus more on aesthetics. In the late 1980's, due to a strong push from this community, the epoxy resin manufacturers introduced drop-in sinks. At first, there were only a few sizes to choose from, but now the available sizes of drop-in sinks almost match the undermounts.

Undermount Sinks

Epoxy Resin Sinks – Undermounts vs. Drop-Ins
Epoxy Resin Undermount Sink
Epoxy Resin Sinks – Undermounts vs. Drop-Ins
Sink Supports - Epoxy Resin Undermount Sink


The following are considerations related to epoxy resin undermount sinks:

  • Sink supports are required – Undermount sinks require supports to be installed in the sink base cabinet to hold the sink to the underside of the countertop which makes installing them a little more time consuming than drop-ins. –Con–

  • Fairly easy to replace – Epoxy resin sinks are very durable but will occasionally crack, typically from thermal shocks caused by dry ice or liquid nitrogen. Since undermount sinks don't get glued into a cutout, as is the case with drop-ins, they are fairly easy to replace. After lowering the supports, any sealant between the top of the sink (either caulk or butyl tape) and the underside of the countertop can be cut, or removed, with a putty knife. –Pro–

  • Several double bowl options – Undermount sinks can be glued together to create double bowl sinks. And they can be glued either width-to-width or length-to-length which creates even more possible configurations. –Pro–

Double U30 Width
Double U30 Sink - glued width-to-width
Double U30 Length
Double U30 Sink - glued length-to-length

Drop-in Sinks

Epoxy Resin Sinks – Undermounts vs. Drop-Ins
Epoxy Resin Drop-In Sink


The following are considerations related to epoxy resin drop-in sinks:

  • No sink supports required – Unlike undermount sinks, drop-in sinks do not require any sink supports. They are installed in a rabbeted cutout in the countertop. And the size of the sink does not matter – larger drop-in sinks do not require sink supports either. –Pro–

  • Some people think they look nicer – As mentioned above, architects and designers really pushed for drop-in sinks and, in general, think they look nicer than undermounts. We could go either way on this one. Drop-in sinks look nice if the joint around the perimeter of the sink is done well during the installation. Undermount sinks are more forgiving in this regard as there is no exposed joint. –Toss-up–

  • Available in ADA-compliant sizes – There is a small offering of 5" deep ADA-compliant drop-in sinks. There are no ADA-compliant undermount sinks due to the fact that they require sink supports. –Pro–

  • Hard to replace – Drop-in sinks are harder to replace than undermount sinks since they get glued into a rabbeted cutout. While maybe not the case if installed with caulk, a drop-in sink will be tough to remove if set using epoxy resin adhesive (the recommended installation method). –Con–

  • Limited double bowl options – There is currently only one double bowl drop-in sink available – D30D – and it is not possible to glue two drop-in sinks together. However, two cutouts can be placed side-by-side with a 2" space between them – a good but not great alternative. –Con–

More Information

Still undecided on which type of sink to choose? Feel free to call us toll free at 866.522.3498 or email us at: info@labfixtures.com. We would be glad to help you make a selection.



Designer / Installer - blandstra@labfixtures.com

Let me know if you have questions or if you would like any additional information regarding this post.