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Heavy-Duty Latex Mattress Foundation
Starting at $360.00 $310.00
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A solid wood latex mattress foundation built to last: 18 kiln-dried spruce slats, double-bolted joints, a 2,000 lb rating and a removable quilted organic cotton cover. The last foundation you’ll ever need to buy, backed by a lifetime warranty. Use it on our optional bed legs (8″ only), in your existing bed or on a metal frame.
Description
Lifetime Warranty
The Last Latex Mattress Foundation You’ll Ever Need
A solid wood mattress foundation built for the weight of natural latex. Eighteen kiln-dried spruce slats, double-bolted joints, a 2,000 lb rating and a removable quilted organic cotton cover: the box spring alternative built not to sag or need replacing, backed by a lifetime warranty.
- Lifetime warranty, built in Tempe, Arizona
- 2,000 lb static weight capacity
- 5.5" low profile or 8" standard
- Use it with bed legs, in your bed or on a metal frame
2k
2,000 lb capacity
Static weight rating
18
Solid wood slats
Spaced under 1.75" apart
2×
Double-bolted joints
No plastic connectors
∞
Lifetime warranty
Workmanship and materials
Lifetime Warranty
Buy It Once. Keep It for Life.
Most box springs and foundations are covered for 1 to 10 years. This one carries a lifetime warranty against defects in workmanship and materials, with or without legs, and its cover and parts can be replaced. It is built to outlast the mattress on top of it, and the next one.
Built not to wear out
Kiln-dried Northwest spruce, 18 slats and double-bolted joints. No springs to sag, no wire grid to bend, no plastic connectors to crack.
Covered for life
A lifetime warranty on workmanship and materials. If a part fails, it is replaced, not your whole foundation.
Mattress after mattress
A firm, flat, 2,000 lb rated base gives every mattress you put on it the firm, flat, evenly slatted support most mattress warranties ask for.
Moves with you
It unbolts into flat pieces that fit through any doorway, so it follows you to the next home instead of staying behind.
Solid Wood Construction
How Is a Heavy-Duty Latex Mattress Foundation Built?
Natural latex is dense. A queen latex mattress can weigh well over a hundred pounds, and it needs a rigid, evenly supported base to stay flat. This wood mattress foundation is built like furniture, not like a disposable box spring.
- Kiln-dried Northwest spruce: straight, stable solid wood rails and slats. No particleboard, no wire grid.
- 18 slats under 1.75" apart: edge-to-edge support with no gaps wide enough for latex to dip into.
- Double bolts at every connection: corner and center rails are bolted twice, with no plastic brackets to crack.
- 2,000 lb static weight capacity: rated for the heaviest latex and hybrid mattresses.
- Removable quilted organic cotton cover: a finished, upholstered look that comes off for cleaning.
Built to order in Tempe, Arizona, and covered by a lifetime warranty on workmanship and materials.
Up Close
The Details That Carry the Weight
Three parts of this bed foundation do the heavy lifting. Each one is solid wood and real hardware.
Every rail connection is bolted twice through solid wood and tightened by hand. Nothing is stapled or snapped into plastic.
Spaced under 1.75 inches apart, so the latex sits on a nearly continuous deck while air still moves underneath.
The optional 6" legs bolt straight into the 8" frame and lift the foundation to 14", with center legs on Full and larger.
Foundation vs. Box Spring
Why a Latex Mattress Needs a Foundation, Not a Box Spring
A box spring is built to flex under an innerspring mattress. Latex needs the opposite: a firm, flat, non-flexing surface. That is the whole difference between a foundation and a box spring.
| Feature | Heavy-Duty Foundation | Traditional Box Spring |
|---|---|---|
| Support surface | 18 solid wood slats on a rigid spruce frame | Steel springs or a wire grid that flex and soften over time |
| Weight rating | 2,000 lb static capacity | Rarely published; designed for lighter innerspring mattresses |
| Connections | Double bolts at every rail, no plastic | Staples on a thin wood or metal frame |
| Cover | Removable quilted organic cotton | Fixed synthetic fabric |
| Moving house | Unbolts into flat pieces in minutes | One rigid box that has to fit through the door |
| Warranty | Lifetime, workmanship and materials | Typically 1 to 10 years, often prorated |
Works With What You Have
Three Ways to Use It
The foundation takes the place of a box spring, so it fits the way you already sleep.
With our bed legs
Add the optional solid wood leg package to the 8" foundation and it stands on its own at 14". No bed frame needed.
In your existing bed
Set it inside your current bed frame, headboard and footboard bed or platform bed, right where a box spring would go.
On a metal bed frame
Place it on a standard metal frame, like our Knickerbocker steel bed frame, for a classic box spring setup.
Choose Your Height
Pick the Height That Fits Your Bed
Both profiles share the same frame, slats and cover. The only difference is how tall your finished bed will be.
5.5"
Low profile
Sold without legs. For platform beds, tall side rails or a lower sleep surface.
8"
Standard
Traditional box spring height for most bed frames.
14"
Standard with legs
The 8" foundation on 6" solid wood legs. No frame needed.
Bed legs are available with the 8" standard profile only. The leg package is sized to your foundation: six 6" legs for Twin and Twin XL, eight for Full and Queen (six around the frame plus two under the center rail). King and Cal King ship as two pieces, and each piece gets its own legs.
Choose Height, Size & LegsSpecs at a Glance
Dimensions, Weight and Features
Dimensions
- Twin
- 38" x 74"
- Twin XL
- 38" x 80"
- Full
- 54" x 74"
- Queen
- 60" x 80"
- King
- 2 pieces, 76" x 80"
- Cal King
- 2 pieces, 72" x 84"
Height: 5.5" low profile or 8" standard (14" with legs).
Weight
- Twin
- 44 lb
- Twin XL
- 45 lb
- Full
- 60 lb
- Queen
- 64 lb
- King
- 82 lb
- Cal King
- 82 lb
Weights for the 5.5" low profile. The 8" standard weighs a little more.
Features
- Natural airflow through open slats
- 18 slats spaced under 1.75" apart
- Supports up to 2,000 lb
- Kiln-dried Northwest spruce, premium S4S wood
- Double bolts at every connection, no plastic connectors
- Easy to take apart and move
- Optional tapered, recessed 6" wood legs (8" only)
- For latex, hybrid, memory foam and polyfoam mattresses
- Removable, replaceable quilted organic cotton cover
- Lifetime warranty on workmanship and materials
Sizes
Choose Your Size
Every size ships free to the continental US. Add the foundation to one of our mattresses in the mattress builder and take $70 off. Current prices for every size and height are in the builder above.
| Size | Dimensions | Pieces | Bed leg package (8" only) |
|---|---|---|---|
| Twin | 38" x 74" | One | Six legs |
| Twin XL | 38" x 80" | One | Six legs |
| Full | 54" x 74" | One | Nine legs |
| Queen | 60" x 80" | One | Nine legs |
| King | 76" x 80" | Two | Legs on both pieces |
| Cal King | 72" x 84" | Two | Legs on both pieces |
The bed leg package is an add-on for the 8" standard profile only. The 5.5" low profile is sold without legs. Foundations are made to order and are final sale; see our shipping and returns policy.
Built for Latex
Why Your Latex Mattress Foundation Matters
An organic latex mattress is a long-term purchase. The foundation for a latex mattress decides whether it stays flat, breathes and keeps its warranty.
Proper support
Latex conforms to whatever is under it. Wide slat gaps or a flexing box spring show through as dips. Eighteen slats under 1.75" apart keep the surface even.
Airflow
Open slats let air move beneath the mattress, which a solid platform or a sealed box spring cannot do. Latex sleeps cooler on an open wood deck.
Warranty protection
Mattress warranties call for a firm, flat, supportive base. A rigid wood foundation with slats under 1.75" apart gives that support for the life of the bed. Check your mattress warranty for its own foundation rules.
Ready to Assemble
Assembly Made Easy
The foundation assembles quickly with minimal effort, minimal tools required, giving you a sturdy, reliable base in no time. Every side, center and end rail joins with double bolts and wing nuts, not plastic connectors. It comes apart just as easily, so moving it to another room or another house is no harder than the first setup.
- 1Unbox the rails and slats
Everything arrives boxed, with the hardware included.
- 2Bolt the frame together
Bolt each corner and center rail together and tighten the wing nuts.
- 3Cover and sleep
Slip on the quilted organic cotton cover, bolt on the legs if you chose them (8" only), and set your mattress on top.
Assembly Video
Watch It Go Together
The full build, start to finish: the frame first, then the optional legs, the slats and the cover. The leg steps start at 5:28.
Prefer photos? See all 24 steps
Unbox
1Full and Queen ship in one box. 2King and Cal King ship in two boxes. 3The box opens along its long side. 4Cut the bands that hold the rails together. 5Rails, slats, bolt kit and cover, ready to go.
Build the frame
6Lay the rails out in position before bolting. 7Line up each end rail and center rail. 8Every joint uses two bolts, washers and wing nuts. 9Tighten the wing nuts by hand to close the joint. 10A finished corner joint, seen from inside. 11The center rail joined to the end rail. 12Side rails and center rail bolted to one end rail. Repeat at the other end. 13The finished frame. No legs? Skip ahead to the slats.
Add the legs (8″ only)
14Attach the two center-rail legs first. 15Center-rail legs in place. 16Then add the corner and side-rail legs. 17A corner leg, seen from inside. 18The frame with every leg attached.
Slats and cover
19Lay the first slat over the side-rail legs. 20Add the next slats over the leg positions. 21Space the remaining slats evenly. 22Hook the cover over one corner, then the opposite corner. 23Pull the cover down over all four sides. 24Press the cover strip onto the bottom rails to finish.
Complete Your Sleep Setup
Pair It With Our Natural Latex Mattress
Every Sleeping Organic mattress is built to order with natural latex, organic cotton and wool. Add this foundation, with its organic cotton cover, to your mattress in the builder and we take $70 off the foundation, and both ship free.
Build Your Latex MattressHeavy-Duty Foundation FAQ
Frequently Asked Questions
Do I need a foundation for my latex mattress?
Yes. Latex needs a firm, flat, non-flexing base with slats close together. A box spring flexes and most bed frames have slats spaced too far apart. This foundation gives a latex mattress the even support it needs and can sit directly on the floor, inside a bed frame or on its own legs.
Is this the replacement for your Premium RTA Foundation?
Yes. The Heavy-Duty Foundation replaces our Premium RTA Foundation. It keeps everything people liked about the RTA, solid wood, ready to assemble, two heights and optional legs, and adds a 2,000 lb rating, 18 slats, double-bolted joints, a quilted organic cotton cover and a lifetime warranty.
What is the difference between a foundation and a box spring?
A box spring has springs or a wire grid inside and is made to flex under an innerspring mattress. A foundation is a rigid wood platform that does not flex. Latex, memory foam and hybrid mattresses all call for a foundation rather than a box spring.
Which height should I choose?
Choose the 5.5" low profile if you have a platform bed, tall side rails or want a lower bed. Choose the 8" standard if your frame expects a traditional box spring height. Add the 6" legs to the 8" foundation for a 14" freestanding base that needs no frame at all.
How many legs come with the bed leg package?
Twin and Twin XL get six legs. Full and Queen get nine, including center legs. King and Cal King are two-piece foundations and each piece gets its own legs. The legs are tapered solid wood, 6" tall, and are available on the 8" profile only.
Will it work with my existing bed frame?
Yes. Use it three ways: on a standard metal bed frame, inside your existing headboard and footboard bed or platform bed in place of a box spring, or on its own with our optional bed legs (8" standard profile only). If your frame has a center support or slats, the foundation sits on top of them.
How much weight can it hold?
The foundation is rated for 2,000 lb of static weight, which covers the heaviest latex and hybrid mattresses with plenty of margin for two sleepers.
Why do King and Cal King come in two pieces?
Two pieces are easier to carry up stairs and through doorways, and each half is still a rigid, double-bolted frame. Side by side under the mattress they act as one foundation, and the leg package covers both halves.
How long does assembly take, and do I need tools?
Minimal tools required. The rails join with the included double bolts and wing nuts, the slats go in, and the cover slips over the frame. The foundation also comes apart the same way, so it is easy to move.
What is the cover made of, and can I remove it?
The cover is quilted organic cotton and it is removable. Take it off to clean it or to pack the foundation flat for a move.
Where is it made and what is the warranty?
Each foundation is built in Tempe, Arizona from kiln-dried Northwest spruce, and it carries a lifetime warranty against defects in workmanship and materials, with or without legs. The cover and parts are replaceable, so a worn cover or damaged part never means a new foundation.
Does it ship free?
Yes, shipping is free to the continental US. Order the foundation with one of our mattresses in the mattress builder and it is $70 off as well.
Heavy-Duty Latex Mattress Foundation
The Last Foundation You’ll Ever Need to Buy
Solid spruce, 18 slats, double bolts and a lifetime warranty. Free shipping to the continental US.
Choose Height & SizeQuestions? Call (800) 625-4042 or email [email protected].
Want the Full Breakdown?
The Complete Guide to Latex Mattresses
Nearly two decades of organic mattress experience, distilled into a 15-section guide. Dunlop vs Talalay, ILD firmness, certifications, off-gassing, allergies, lifespan, and how to choose your perfect configuration.
