Advice for making a layered foam V-berth mattress

[Copacabana]

I did a search here and found a few mentions of people making a layered foam mattress, but no details on the materials used. I'd like to make a new V-berth mattress and would like to do it right. My idea is to use a layer of denser foam on the bottom for support and a layer of softer foam on top for comfort. I'm planning on using standard upholstry foam (for sofas and such)- no exotic foam like memory or latex.

My current mattress is a single layer of 7cm (3 inch) fairly soft foam. I'd like to make the new mattress 10cm thick (4 inches) at least. My idea is to buy the foam in sheets, cut them to size and then glue the layers together.

My question is what densities should I use for each layer? Ideally I want a firmish bed, but not a plank!

Has anyone gone through this process and, if so, what densities and thicknesses did you use?

Thanks in advance.

[pmagistro]

Your easiest option might be to purchase a king sized foam mattress off Amazon and cutting it to size. I did so for an RV and have been very happy with it. Memory foam is temperature sensitive, so it turns to a "plank" in very cold temperatures but as long as the temps are comfy the bed will be too.

[deltaten]

Copa:
I found the 30-some y.o. cushions too soft and would sink thru to the hard points by midnite or so. I then added a 3.5" stiff memory foam. Only lasted till maybe 3 a.m. Figured I needed something between to spread the load w/o being too stiff. I had a couple sets of cheap harbor freight interlock floor pads aboard for insulation, so I figgered WTH?
Worked out marvelously! Comfy, with only adding half an inch. Still need to glue to the memfoam and add gripper stuff to the bottom so's the layers don't s!ide and seperate.
Next trick will be to cut out the dead level (always feels like you're falling off!) Seat, leaving adequate edge support, and lacing a net, like a hammock or chaise lounge

[Stu Jackson]

Only YOU can decide what is right for you. Everyone is different.

Go to a foam shop and try them out.

[Copacabana]

Originally Posted by deltaten

Copa:
I found the 30-some y.o. cushions too soft and would sink thru to the hard points by midnite or so. I then added a 3.5" stiff memory foam. Only lasted till maybe 3 a.m. Figured I needed something between to spread the load w/o being too stiff. I had a couple sets of cheap harbor freight interlock floor pads aboard for insulation, so I figgered WTH?
Worked out marvelously! Comfy, with only adding half an inch. Still need to glue to the memfoam and add gripper stuff to the bottom so's the layers don't s!ide and seperate.
Next trick will be to cut out the dead level (always feels like you're falling off!) Seat, leaving adequate edge support, and lacing a net, like a hammock or chaise lounge

Thanks for the reply. I'm thinking I may just add a 2-inch memory foam topper to the existing V-birth foam (glued to the foam and then make new covers). The only thing that worries me is that it might be a little warm at night- I live in the tropics. I was originally thinking about layering different density regular poly-foam to get a comfortable mattress, but I think the price will be quite high. It's probably cheaper to go the memory foam topper route.

[Copacabana]

I just ordered a 4cm (almost 2 inch) thick gel memory foam topper. I hope they're right when they claim it is cool to sleep on!

In the end I'll just glue this over the original foam (after a test sleep). I'm redoing all the upholstry in the boat, so it's not a problem to have a thicker mattress.

[Scaramanga F25]

I have had wonderful v-berth cushions and aft cabin cushion made with 6 inch foam.

[Dave22q]

I added a 4" eggcrate type (one side flat, the other 2-3" cones) foam topper to my V- birth mattress with a cloth topper. Fits well and bottom sheet held in place by elastic straps so no gluing needed between layers. Worked well but needed to replace after 5 years. Stays cool, low cost.

[bcboomer]

We find memory foam too hot. We ordered 2" firm, 1" medium and 1" soft "super-lux" poly foam from a popular on-line foam supplier. You don't need to glue it together if you wrap a padded mattress cover over it. We added a 1" top layer of polyester fibrefill to make it a bit more luxurious feeling and ventilation. The admiral is really happy with it so it is a success.
I'm not sure how long it will last since a seat cushion I made with their best quality foam didn't last a year.
Other cushions I have made from a local supplier have been very durable in comparison. Might be a case of "you get what you pay for".
If it wasn't so heavy I'd get latex but we have storage under the bed.

[Cadence]

Forget the memory foam it doesn't support you. It remembers were you needed the support. JMHO

[guyrj33]

Memory foam holds a lot of water, don't let it get wet.
You can use upholstery silk to make stuffing the cushions a little bit easier. It's thin soft plastic that you wrap around the cushion, vacuum the air out to compress the foam and slide into the cover.

[foufou]

You might also consider the Froli springs. Under the foam which adds comfort and solves the moisture condensation problem

[alaskaflyfish]

I just re carpeted my house and bought the highest grade foam underlayment carpet pad. I had a large chunk left over so I threw it under my V birth 3" cushions and "damn", what a difference in comfort. No aches or pains and can sleep all night. Its a stiff water resistant foam with a plastic covering on both sides. This being under a real soft foam is a good combo for me and was an inexpensive way to fix a comfort problem.

[Jdeuel]

Just bought a 12” queen memory-foam bed-in-a-box on Amazon for my son’s room. $179 delivered and ridiculously comfortable.

IIRC, they came in thicknesses of 6”, 8”, 10” and 12”. You should be able to get an idea of the firmness from the reviews. Depending on the size of the berth, you might do two twins.

One thing: the mattress stunk to high Heaven for a good week when we released it from the bag. Pretty cool watching expand from the size of a medium cardboard box into a big ol’ bed.

[Hunky Dory]

I am doing exactly as you are. I checked with a foam manufacturer ( bhart@sureline.ca )
He recommended 3" of 2050 IFD a medium firm,( test measure for open cell polyurethane foam). This product has no fire rating. Then using a water based adhesive and glueing a 1"top layer of Serene a new product that is open cell not affected by temperature. This combination does not engulf you like memory foam. Approximate cost for materials equal to queen size is $325. Canadian,