I receive many requests for foundation recommendations … especially for all latex mattresses which are heavier and need a strong and suitable base. There are many different threads on the forum that talk about this so I thought I would amalgamate them into one which gathers all the information together in one place.
This post applies to all foam and latex mattresses (without an innerspring). For more information about foundations vs “active” box springs and the type of mattresses that are most commonly used with each see post #3 here and post #2 here which include more information about the main functions of a foundation or box spring (or other types of support systems such as a solid surface or slatted platform bed).
The first and most simple option is to use a foundation that is recommended by the manufacturer of your mattress. Because the mattress manufacturer knows which type of foundation is suitable for their mattress and meets their warranty criteria … this can save lots of research and you know that you will have a foundation which the mattress manufacturer themselves knows works well with their mattress. If you do decide to choose an alternative then I would make sure that the foundation and bedframe meets the manufacturer’s warranty criteria.
For those who may want to do some research into other options either for reasons of price, function, or because the manufacturer doesn’t offer one … here are some guidelines and choices …
An all latex mattress generally needs and does best on a strong solid base with enough supportive surface to make sure that it doesn’t sink through any gaps and that the base is strong enough and supported on the floor well enough to hold the weight of the latex mattress and the people that sleep on it. Normally a slatted wood base with solid slats that are no more than 3" apart (or preferably less) is best for latex (up to about 5" would generally be fine for a polyfoam support core which is stiffer than latex but less would still be preferable and would generally be stronger and more evenly supportive). A metal wire grid base with a non flexing or “semi flex” wire grid with narrow gaps and a strong fabric on top to even out the support surface (to help prevent the latex from sinking in to the gaps in the wire grid surface over the longer term) can also work well but over the longer term may allow the latex to sag into the gaps between the wires. These can either rest on legs that are included and screwed onto the foundation or on a strong suitable steel frame designed to hold a foundation and are widely available. For a mattress that uses a polyfoam base layer which is stiffer and less flexible than latex (won’t bend into any gaps as easily) then the manufacturer’s recommendations about the number of slats or the gap between them should be followed.
In some cases though … a more flexible slatted base with closely spaced curved more flexible slats or another type of flexing surface such as a box spring, is also recommended by a manufacturer and can have some advantages as part of a complete “sleeping system”. These act like another layer of the sleeping system and will “give” under the heavier parts or pressure points of the body (like the pelvis/hips and shoulders) as long as the mattress on it is thin enough that this bottom “layer” of the sleeping system can affect the feel and performance of the mattress.
Another (generally more expensive) option that is similar to a flexible slatted base is a tension adjustable slatted base which typically uses similar flexible curved slats or another flexible surface that can be adjusted to allow for different tensions or firmness levels in certain areas of the body. This can fine tune the alignment and performance of the mattress and “firm up” the support under the hips or “allow” the shoulders to sink down more. These work best with mattresses that are thin enough for the adjustments to be effective on the surface of the mattress.
A slatted platform bed is also perfectly suitable as long as the slats are spaced close enough together (again 3" or preferably less for latex or up to about 5" or so or preferably less for a polyfoam support core) and the bed has a center beam with good support to the floor (in sizes above a twin) so it doesn’t sag. Putting the mattress directly on a bed like this would make a separate base or foundation unnecessary.
Position adjustable bases allow you to raise and lower the head and feet or in higher end models and often include other features such as a vibrating massage, different types of remote controls, and sometimes all kinds of other “bells and whistles”. These have many uses and can be desirable for those who work, read, or watch TV in bed or enjoy the other features of the system and can be used for other reasons or even medical conditions that are either helped by or require a non flat sleeping positions for pressure relief, support, or to alleviate some health or medical conditions. These are usually suitable for a latex or any “bendable” mattress as long as the weight limits of the motor are not exceeded. If there is any doubt about the suitability of an adjustable bed for a particular mattress then the recommendations or warranty conditions of the mattress manufacturer should be followed.
There are also foundations which are both position and tension adjustable and include other optional features (such as massage) as well.
Regardless of the type … a foam mattress generally needs a strong and evenly supportive base (suitable for the materials used in the mattress) with a strong support system that can ventilate and has enough supportive surface area to prevent the latex (or other material) from sinking through any gaps in the foundation.
There are also many people who believe that a solid platform surface such as plywood is also suitable but this reduces the ventilation of the mattress and can increase the risk of moisture in the mattress and lead to the possibility of mold and mildew and even an increased dust mite population in the mattress. While the risk of this is small with latex and other “treated” materials or foams … I personally prefer options that have the least risk and promote the ventilation of the mattress so I am not one of those who believes that a solid platform base is the best option. For those who have a solid platform foundation then a product such as a slat conversion or a coir bed rug may be a good idea.
Most bases or foundations also come in various height options which allow the surface of the mattress to be at a certain height. They can be put on a metal frame or on a platform bed or bed frame and many also have attachable legs of various heights to raise them off the floor in which case they don’t need to go on anything else as long as in sizes above a twin they have good center support to the floor. In all cases … the mattress needs to rest on an evenly supportive base that will not sag or weaken over time under the weight of the mattress and the people on it.
There are also some manufacturers who design all foam mattresses as part of a system for use on an “active” box spring which will change the feel and performance of the mattress compared to a rigid non-flexing foundation. This is less common with an all foam or latex mattress and is generally used with innerspring mattresses. These are generally used with a thinner foam mattress and like a flexible slat foundation are designed to be part of the performance of the whole sleeping system. If you have tested a mattress on an “active” box spring, then it’s important to be aware that using the mattress on a non-flexing foundation (or the other way around) can significantly change the feel and performance of the mattress and a mattress that works well for your body type or sleeping style and positions may no longer be as suitable for you on a different base than the one that you tested in the store.
Some more specific information about each type of foundation:
The most simple, convenient to ship, and often the most economical of these is the KD (knock down) foundation which is shipped in pieces and assembled at home with very simple instructions. They are mostly good quality but sometimes the quality can be mixed and I have heard a few stories and know of examples where lower quality (with slats that are too far apart or uses inferior or different wood than is advertised) is being shipped or slips through from the manufacturer in which case, of course, it would need to be replaced. Ordering from a reputable outlet can make sure that any lower-quality foundations will be replaced. In the “best” version, they are good value, easy to ship and set up, and cost less than most slatted wood foundations. These foundations are usually available in normal height (9"), low profile (5") or even bunkie boards (2"). Always make sure you know the amount of any gaps between the slats.
With wood foundations, the more wood that is used and the higher quality of the wood and construction that is used, the more expensive they are. They can also include surface materials such as wool or cotton padding on top which can increase ventilation in the foundation mattress interface, increase support in the foundation “gaps” and provide a softer surface and decrease any possibility of damage to the mattress. Some of these are built like a tank and use two center supports instead of one for higher-weight mattress/people combinations. Some examples from our online site members who ship include (make absolutely sure that the gaps are less than 3" if you have an all latex mattress):
For those of you who enjoy DIY projects, one of our forum members has put together a list of materials and detailed instructions for building a very strong low profile king size foundation that bolts together with 6 bolts for about $300 which you will find in post #7 here (thanks Minok). There is also another 10" DIY foundation design with detailed instructions and a list of materials in this thread, as well as in post #13 here.
Steel grid non flex “platform bed style” foundations:
I should note here that there are some latex mattress manufacturers who would suggest avoiding these for an all latex mattress because of the risk that the latex will sink into the wires and the gaps between them over the long term and reduce the life of the mattress because of the lack of supporting surface area of these types of foundations. If you do choose one of these for budget reasons for an all-latex mattress, I would suggest using a model with the most possible longitudinal wires and cross wires to help provide better support between the wires.
There are quite a few manufacturers of a newer type of mostly 14" platform frames which can be folded for shipping and are easy to set up in the home. They are each re-branded into many different names. They all are fairly similar but there are some noticeable differences between them. Some are quad-fold and some are bi-fold. Some have add-ons available like headboard and footboard attachments and different rubber corners and feet, and some have covers and bedskirts of various types available. Some also have more longitudinal wires running head to foot than others (the twins seem to run from 5 - 11 wires) or use different gauges of wire. The ones with more wires or closer spacing in the grid would provide more even support and less space in the grid for the mattress to “sag” into. I would only use the versions with the smallest gaps between the wires and a strong fabric on top (or coir bed rug) for an all-latex mattress (if you use them at all) because the support surface area is smaller than most slatted foundations or platform beds. There are also different weight ratings but they all seem to be able to hold a considerable amount of weight. There are also some where the king and queen sizes seem to be missing the longitudinal wires in the middle section which wouldn’t offer enough support in this middle area (and which I would avoid). I would also always confirm the actual number of wires in any of these styles of platform beds since the pictures shown on their websites may not be the same size as you’re considering ordering. Some examples from our online site members who ship include: [br]
Wire grid foundations:
There are also wire grid foundations that can be used on a steel or wooden bedframe that are either all steel or have a wooden base of different types underneath the wire grid (a manufacturer can use different bases to support the wire grid). The wires grid systems are often made by Leggett & Platt or Hickory Springs. They generally have a more evenly supportive surface with various types of grid patterns or use a higher gauge wire and look more like a typical foundation but are usually a little more costly. These are sometimes referred to as “semi-flex” or “min-flex” foundations, but they really don’t flex at all. You’d want to check with your manufacturer to make sure that this type of foundation would be appropriate for any mattress you might be considering, especially all-latex. Some examples from our online site members who ship include: [br]
Flexible slatted foundations:
These are foundations that have flexible slats that are designed to be a more “active” part of a sleeping system and use different methods to provide some additional flex under the mattress.
Tension and/or position adjustable flexible foundations:
These flexible slat foundations have the option to adjust the firmness under different parts of the body which may help with proper alignment. Some examples from our online site members who ship include: [br]
Position adjustable bases (AKA adjustable beds):
The adjustable bed thread here has some examples and comparisons of some of the more common types and manufacturers of adjustable beds and some sources for each that you can use as a “value reference” for a purchase. Some examples from our online site members who ship include: [br]
Slatted platform beds:
Platform bed sets use the same or similar support structure as platform foundations, but they are built into an actual bed base, sometimes with storage underneath or other times suspended on legs or on a pedestal. The same guidelines would apply to these pieces of furniture as apply to the platform foundations listed previously in this post. There are thousands of different designs available for platform bed bases, mostly from furniture stores and manufacturers. Some examples from our online site members who ship include: [br]
Many local members of our site who do not ship, other local retailers, or manufacturers will also sell you a foundation for a reasonable price, and a few phone calls to find out may be worthwhile as long as you can verify that the foundation is suitable for your mattress.
There is also more about steel bedframes to support a foundation or box spring and raise it off the floor in post #10 here.
As mentioned previously, if you have any doubts about the suitability of a particular choice or want to make sure that it meets the warranty criteria, always check with the manufacturer of your mattress (or read the warranty) because warranty requirements can vary from manufacturer to manufacturer.
Hopefully, this will help sort out most of the foundation, base, frame, bed, and platform options for foam mattresses.