What’s the best foundation for a plain innerspring mattress? (one with verticoils)?

Would it change the feel on a solid slat platform versus the box spring?

Also, question- would taller coils ( 5 in versus 7 in) in theory feel firmer or softer purely based on the height?


Hi pressurepts,

You can read more about foundations and “active” boxsprings and the types of mattresses they are generally most suitable for in post #2 here.

Generally the one that is suggested by the mattress manufacturer or at least is acceptable under their warranty criteria is the best choice.

In most cases yes … it can make a noticeable difference and if you tested a mattress on an “active” boxspring and it worked well in terms of PPP (Pressure relief, Posture and alignment, and Personal preferences) then that is what I would include in your “sleeping system” because a firm foundation can change the feel and performance of the mattress vs a more flexible base and may not be the most suitable choice for an innerspring mattress.

It would depend on whether it was an apples to apples comparison (same type of coil shape, diameter, and type, number of turns, coil gauge, method of connection to the coils next to it) but if everything else was the same then a taller coil with the same number of turns would have a greater pitch angle and feel firmer.