Sensus vs Aerus foam

I am going to order a mattress from Rocky Mountain outlet and trying to decide between Sensus and Aerus. They appear to have similar ILD and only difference is density which - per other post in this forums - only impacts durability and support. I know that Aerus is supposed to have more “airflow” through it.

Any feedback on how Sensus would feel vs Aerus? Any reasons other than durability to get Sensus?

If I have a Venus (layer) on the top - does it matter whether layers underneath are Sensus or Aerus?

Thank you

ive tried aerus before. its pretty nice quality. some foams just stay much cooler than others. for instance i believe though am not 100% sure that the foam using the beautyrest truenergy is the 4 lb foam sold by hickory springs which is their preserve foam. that foam u could sleep right on top of and not get hot. myluxurymattress sells it

I have samples of both in hand and the airflow is negligible, definitely not enough to compromise durability. Go with the Sensus.

Hi aoysgelt,

Lower density foams tend to be a more responsive, softer feeling, and have a narrower temperature range than higher density foams. Of course this also depends on the many variations of the different qualities of memory foam that are possible in any density so the opposite may hold true for some comparisons for memory foams that have been designed to have certain properties.

Aerus has a higher airflow than Sensus and even other types of more “breathable” memory foams and also has a higher sag factor than other memory foams (gets firmer faster) so may also feel firmer than similar types of faster response 4 lb breathable memory foams. There is some more general information about it here.

Sensus on the other hand has a firmer IFD (ILD) but also has a wider temperature response range which means that how firm or soft it feels will depend more on the person sleeping on the mattress, movement on the mattress, and on the other temperature and humidity variables.

Rocky Mountain Mattress has a good series of short videos here which talk about the different memory foams that they carry which may help you decide between them.

It’s interesting to see that out of the FXI foams in open air cooler conditions that the 5 lb Sensus has the fastest response rate followed by the 4 lb Aerus followed by the 8 lb Venus. It’s also interesting that the 4 lb Aerus and the 8 lb Venus have the same IFD rating even though they will feel different while the Sensus is the firmest at 14 IFD.

Hope this helps.


I already spoke to Rocky Mountain… What I have posted is close to their suggestion - I wanted to get other people’s opinion on it.

From your other post - I think you recommend to choose Sensus vs Aerus - correct?


Hi aoysgelt,

That’s great. I would certainly put more weight on what they said than other opinions … including my own … because they have much more real world experience with these particular materials and combinations than I do.

For your circumstances and the preferences you gave yes (although some of the other differences you haven’t mentioned as a priority may also be important to you). This thinner layering also leaves room to add additional softness or fine tuning if its needed rather than trying to “take away” memory foam layers that are too thick. I tend towards being quite conservative in terms of layer thickness with the use of memory foam in general because it is a more “tricky” material to use and get right because of how its properties and performance varies with heat, humidity, time spent on the mattress, and other factors.


Should I break setup into even more layers? Original was
1in Venus
2in Sensus
2in 35ILD
3in 40ILD

I can break 3in 40ILD into 2in + 1in to allow an extra inch of memory foam in the future or to substitute 1in of 30ILD or something similar?


Hi aoysgelt,

I personally wouldn’t no. Thinner multiple layers will act differently (generally softer) than the same thickness in a single layer and you may lose some durability as well because they compress more individually. There is also an increased risk of shifting and some loss of stability as well unless the layers are laminated (which would defeat the reason you were considering it).

I am not a fan of ordering as many thin layers as possible over using the minimum layering that gives you the best odds in the first place and still leaves room for a little extra if needed. When you are down to this level of detail you are also introducing a level of complexity that will usually do more to hurt than it will help.


in the worst case u can always buy aerus/sensus 2-3" to put in if its not performing properly. I think alot of it depends on your weight and what kind of firmness u want. I think 3"-4" is ideal but 3" could be perfect and 4" could be too soft. You kind of have to just try it and see how it is…:wink: