Layering Foam For Mattresses and Cushions

Published: Thursday, February 4, 2021

Did you know that you can layer different types of foam to achieve a custom firmness and feel? Layering foam also allows you to add more breathability and prevent moisture buildup in your cabin mattresses and boat cushions. The Sailrite experts have weighed in and offer their favorite layering techniques for creating the perfect foam application. There are three layering options that we recommend, so you’re sure to find a formula that works for your specific needs.

Choosing foam for your boat cabin is very much a subjective process. There are a variety of factors to consider, and you have to determine what’s best for your boat, where you live, and your own sleeping comfort level. In a practical sense, foam layering allows you to build your desired thickness so you can have a custom mattress to your exact specifications.
In addition to height, layering various types of foam also creates a unique foam firmness. Foams with a higher IFD (Indentation Force Deflection) are firmer and won’t compress as easily as foams with a low IFD. For example, a firm polyurethane foam has an IFD of 60 lbs., which means it takes 60 lbs. of pressure from a 50-square-inch circular plate to compress the foam by 25%. For comparison, a polyurethane foam classified as a medium firmness has an IFD of 45 lbs.

We recommend a combination of foams with both a higher and lower IFD. The higher IFD foams should be on the bottom of your layered assembly — think of the firmer base layer of foam as a stabilizer like a box spring on a mattress. It gives you support even if the softer top layer starts to bottom out over time.