Yes, it is super firm and very flat.
However, the support is exceptional, from head-to-toe and edge-to-edge.
We also felt comfortable side sleeping on the Firm side, although lightweight sleepers will need more cushioning.
Our testing panel found the Extra Firm side of the Plank Mattress comfortable for back sleeping.(Image credit: Future)
There are some minor nitpicks.
The temperature regulation could also be improved, as our lead tester woke up warm on several mornings.
However, very hot sleepers do have the option of upgrading to the cooling GlacioTex cover.
Our testing panel found the Extra Firm side of the Plank Mattress comfortable for back sleeping.(Image credit: Future)
Plank often increases the discount over the major holidays, including theBlack Friday mattress sales.
On these occasions, the discount jumps to 30% off.
This is the best time to buy we’ve never seen 30% off bettered.
Plank offers a 10-year warranty, which is aligned with the industry average.
Plank has created this dual design by building from the center out.
This foam has very little yield you lie on top of it, and you don’t sink in.
On this side, you’re mostly feeling the support foam.
A continuous pattern quilted design keeps the top flat, for minimal lift and only the slightest cushioning.
If you prefer a bouncier feel, you could upgrade to the Plank Luxe Mattress.
Our testing panel found the Extra Firm side of the Plank Mattress comfortable for back sleeping.(Image credit: Future)
But don’t worry, it’s still very firm.
After a breaking-in period, the Extra Firm side did soften up slightly, but only slightly.
Side sleeping, however, is uncomfortable.
The Firm side of the Plank Mattress provides minimal contouring for side sleepers.(Image credit: Future)
The Extra Firm Plank, on the other hand, has almost none.
When our lead tester slept on her side she woke up with a numb arm.
To measure pressure relief, we placed a 35lbs weight in the center of the mattress.
We measured a 2.5" sink in the center of the Firm side of the Plank Mattress.
On the Extra Firm side, it sank just 1.5", indicating limited pressure relief.
Plank rates it eight out of 10 for firmness and our testing panel agreed.
Our lead tester could sleep on her stomach or side and still wake up comfortably.
Our box arrived damaged…(Image credit: Future)
The Firm side should also appeal to back sleepers.
But it’s worth noting that for some, the Plank will be too hard regardless of sleep position.
There’s another aspect of comfort to consider here: the dual-sides.
…but the mattress was otherwise unscathed.(Image credit: Future)
We tested each side of the mattress for several weeks, flipping between them just once.
The Extra Firm side is notably harder than the Firm side.
Shipping is fast and free, but there’s no option forwhite glove delivery.
Our at-home test model quickly sprung into shape once we removed the plastic.(Image credit: Future)
Inside the box the mattress was undamaged.
There was a mildoff-gassingsmell to the Plank Firm but this dissipated quickly.
The box, however, had a terrible smell.
Our model quickly sprung into its full shape.
But unlike many mattresses, the setup doesn’t end when the Plank Firm is on the bed frame.
As a double-sided mattress, you’re going to want to flip it occasionally.
This is a mattress that could really benefit from a set of handles.
Without them, it’s tricky to move the mattress from one side (feel) to the other.
One minor nitpick is that there’s no labeling to show which side of the mattress is which.
We placed it on a slatted bed frame dressed with breathable covers.
This gives it excellentmotion isolation.
When one person climbs into bed, the surface hardly moves at all.
We dropped the weight from 25", 12", and 4" away from the wine glass.
At 25", the glass stood still on both the Firm and Extra Firm side.
However, despite testing the Plank Firm during a cool winter in the UK, it still got warm.
And if you regularly experience night sweats or overheating, you might feel uncomfortable in the morning.
Hot sleepers should consider upgrading to the GlacioTex cover.
GlacioTex material is used in several of ourbest cooling mattresspicks and has a cool-to-the-touch feel and a slicker surface.
This upgrade will add roughly $100 - $150 to the overall price.
The Plank Firm is strong right up to the corners.
One of our testers highlighted the support at the sides as their favorite feature of the mattress.
To back up our subjective tests, we used a weight to take an objective measurement.
We placed a 35lb weight on the corner and side of the mattress and measured how much it sank.
On the Firm side, it sank 2" at the edge and 2.5" at the corner.
There are some criticisms.
Several customers complain about waking up hot, which matches our experience.
Some customers also have issues with the firmness, although here it can go either way.
If you want no softness whatsoever, consider aJapanese floor mattress.
Should you buy the Plank Firm Mattress?
The Firm side has a wider appeal, with an added layer of cushioning helping to offset the hardness.
The flip side of this is pressure relief.
For back or stomach sleepers, there’s enough relief on either side to get comfortable.
For side sleepers, the Plank Firm can feel uncomfortably hard.
Even on the ‘softer’ Firm side, there’s limited cushioning.
And speaking of flipsides: is the double-sided nature of the Plank Firm more than just a gimmick?
This is a premium bed, so keep an eye out forSaatva mattress sales.
