Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Aug 31, 2010 8:46 PM
Joined: Aug 16, 2010
Points: 35
I was going to pick this base up this weekend for my new king SleepEZ, but looking at the design I'm not sure I understand the layout of the adjustable slats.

 

The adjustable slats are just regular slats with a shorter slat attached to the bottom and 2 sliders that hold them together.

If I am understanding the design correctly, moving the sliders to the center takes the extra slat out of the equation and makes the slat the same tension as the non-adjustable ones.

Moving the sliders towards the ends progressively engages the short slat underneath and adds extra stiffness and less "give".

The adjustable "zones" appear to be positioned at the shoulder and hip area.

This doesn't make sense to me... why would one want to stiffen the shoulder and hip zones relative to the lumbar? Wouldn't you want more "give" in these areas?

<a href="http://s98.photobucket.com/albums/l273/Ganderson_01/?action=view&current=laxeby.jpg" target="_blank"><img src="http://i98.photobucket.com/albums/l273/Ganderson_01/laxeby.jpg" border="0" alt="Photobucket"></a>

This message was modified Aug 31, 2010 by Ganderson
Re: Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Reply #1 Aug 31, 2010 10:35 PM
Joined: Aug 31, 2007
Points: 404
Beats me!  I was reading on a mattress maker's website just yesterday (can't remember the brand, sorry), that discussed how their mattress was zoned to provide more support for the shoulder and hip areas.  I reacted just like you - don't you want more, not less, give under those areas??  So I'm with you with the "What the heck?!" reaction.
For static equilibrium the support must push up at each point as the body weight pushes down!
Reply #2 Aug 31, 2010 11:00 PM
Joined: Dec 11, 2009
Points: 113
The force exerted by your "body at rest" ... downward at each point along the contuinuum of your spine must be counterbalanced by the collective force along the body "pushing upward" by the mattress.   The springs in the mattress or the foam acting like a million little springs... are being compressed some linear amount equal to some force in lb ft or inches so that the total displacement of the springs x lb per inch = your weight.

If those areas arent beefed up, they will sag.  The mattress designers problem is that we are eached shaped and weigh differently, and some lie on side or back.

The biggest issues come from overall weight.. and then side or back.

A heavier person needs either stiffer springs or more of them, etc. or will sink to where you will feel a sag.

When you lie on your side...  the mattress should accommodate the shoulder and hip extending beyond the rest of the body and bearing much of the weight.  The extra displacement of the shoulder and hip are likely enough to not need extra stiffness under the hips.

However, the back sleeper will need a stiffer mattress because the butt doesn't extend (mostly!) .. but remember to balance the down weight the mattress must displace x inches x y ft pounds per inch = your weight.

This really summarizes the design problem.  The advent of memory foam to spread the entire weight more or less linearly along the entire toros was designed to deal with this.

You are aware that Latex ";pushes back"  because it functions like a continuous, uniform spring..and the deepest intrusion = the highest resistive force.  But all mattresses ";push back" to fulfill the first law of physics.  If the forces weren't balanced... you would be falling! 

This adjustment appears to  allow the user to adjust those areas.  Clever.

Many mattresses now advertise "zoning" a fancy word for "stiffer under your butt"... softer under your shoulder.

shovel99

Bach Eng. Science and Mechanics

GA Tech

 

Re: Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Reply #3 Sep 1, 2010 12:13 AM
Joined: Aug 16, 2010
Points: 35
From a mechanical standpoint countering the areas exerting greater force with equal and opposite (greater) force makes some sense depending upon what you are trying to accomplish.

 

However, from a mattress standpoint, where physical comfort and support are paramount it seems like countering these weight bearing areas with higher counter-force is a recipe for discomfort.

Here are a couple of other slat systems whose descriptions indicate that they are designed to counter possible pressure points (shoulders & hips) with less counter-force.

<a href="http://s98.photobucket.com/albums/l273/Ganderson_01/?action=view&current=slatbase.jpg" target="_blank"><img src="http://i98.photobucket.com/albums/l273/Ganderson_01/slatbase.jpg" border="0" alt="Photobucket"></a>

 

 

<a href="http://s98.photobucket.com/albums/l273/Ganderson_01/?action=view&current=slatbase2.jpg" target="_blank"><img src="http://i98.photobucket.com/albums/l273/Ganderson_01/slatbase2.jpg" border="0" alt="Photobucket"></a>

This message was modified Sep 1, 2010 by Ganderson
Re: Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Reply #4 Sep 1, 2010 12:26 AM
Joined: Aug 31, 2007
Points: 404
Ganderson: now that makes sense.  When I sleep on my side (have been unsuccessful at changing myself to a back sleeper, sigh), I want my hips and shoulders to sink into oblivion but I want my ribcage and waist supported, otherwise I turn into a smiley-curved banana - a painful one at that.  This is what is currently happening on a twin pocket coil I have topped with a too soft MF.  I melt right through the 3 lb MF so that my shoulders and hips hit the pocket coils underneath resulting in said shoulders and hips being pushed skyward while the ribcage/waist lie neatly along the coils resulting in above noted painful banana position.  What I really need is a gazillion angels to descend from heaven to delicately balance me on their ever-so-responsive fingertips while I sleep - is this too much to ask?!
Re: Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Reply #5 Oct 2, 2010 11:16 PM
Joined: Sep 6, 2008
Points: 87
I initially thought of getting a Euro Slat base ... but after reading the V-Zone product and speaking with Dewey, I think I am going to go for the V Zone bed from Flobeds.

It will achieve what you are discussing Diane ... the support in the right areas and more plushness in the butt and shoulders.  I am 6'5" so when I sleep on my side, there is quite a bit of shoulder to be absorbed by my current S Brand pocket coil mattress.

Re: Ikea Laxeby Slatted Base - I don't get the point of the adjustability...
Reply #6 Oct 5, 2010 4:55 PM
Joined: Oct 3, 2010
Points: 809
Interesting discussion ... and something that I talked to many people about (mostly mattress manufacturers at some level) and experimented with by lying on mattresses until it "sort of" became clear to me.

The first assumption is that the best sleeping position is one where the spine is either straight (side sleeping) or follows it's "natural" curve (Back and stomach sleeping). If you imagine someone sleeping on their side on a sheet of plywood, then their hip and shoulder area would be "pushed up" and there would not be enough give in these areas to create a flat spine. On the other hand if someone was sleeping on something extremely soft, the shoulder and hip area could sink too far into the mattress and their spine would be "bowed" the other way.

This is further compounded by the fact that in most people, the shoulder area (for side sleeping) is wider than the hip area but the hip area carries more weight and would have a greater tendency to sink further than the shoulder (more pressure). In this case the shoulder would need to be softer than the hip to help create a flat spine.

So in the case of an adjustable slat base, and depending on the makeup of the mattress and the weight distribution of the person, the slats may be needed to either "firm up" the hip area (if it was sinking too far) or soften it up (if it was not sinking enough). The adjustment needs to be "relative" to the other areas of the body.

So in a "hard" mattress, the hip area may need to be zoned softer so it can sink in more and in a "soft" mattress the hips may need more support so it sinks in less relative to the shoulders.

This finally all made sense to me once I thought about it relative to creating a straight spine.

Phoenix