How to firm a mattress?

[Lynda2021]

Trying to firm up a queen mattress. Slat base bed. Looking to use a solid timber, probably plywood on slats under mattress. Is waterproof the same as marine?  How thick should it be?  Slats are 2cm. I measured 185x145cm and allowing for ease of fit, I’m maybe looking around 165 x 125cm. Cutting in half to fit in car = 800mm x 600mm.

appreciate advice thank you.

[Jason]

Sorry for the slow reply @Lynda2021. One of our resident Bunnings D.I.Y. experts Mitch has had to take some unexpected leave. His partner-in-crime @EricL will be back on the site later today and would be happy to assist. Let me also tag some other helpful members in @prettyliving, @Tara86 and @TedBear for their thoughts in the meantime.

Thanks for your patience.

Jason

[Jewelleryrescue · Accepted solution]

Hi  @Lynda2021 

You can use ply as  thin as 6mm as the weight of the matteress will be distributed over a broad area. But make sure a slate  supports any joining  5 mm ply sections for proper support.

Marine ply used in wet environs 

A cheap product I used is  yellow tounge flooring per sheet is inexpensive and then you can use your bed as a dance  floor as it is thick but down side  it is heavy. Measure  your bed frame maybe have bunnings cut it to size to get it home. flooring sheets are  also water resistant

Cut sections of  flooring or ply to fit across  the beds neatly   like rungs on a ladder but pushed together . You have the  dimentions

the last piece may need to be trimmed to fit across the bed and a bit cut of at the  base .Cut like this and it will fit in car easy.

Place the Flooring on top of the slates and a few screws or nails will hold every thing nicly in place.

[Lynda2021]

Thank you so much. I might pass on the flooring as it is heavy. I’m 72 and have steps to climb!   I was thinking 1 piece cut in half length ways but that puts my body more or less over the middle, ie, where the sheet is cut. Would you recommend I connect those 2 pieces with a flat kinda join?  Would it be better to cut the sheet in 2 pieces width ways rather than length ways. Sorry if I’m asking too many questions. 
thank you. 

[Jewelleryrescue]

Hi  @Lynda2021

 Please feel free to ask as many questions as you want thats why  the workshop is here to  help all people of all skill levels as long as you need assistance and advice.

Because you are going to place 6 mm ply on top of slats the weight will be evenly distributed regardless of ply cuts  if you cut the ply length ways it will work well as all the ply edges supported on top of the slats you will not have to join the ply in any way just sit them side by side and put small nails or screws it to the under slats to lock it in position just in case you need to flip the matress or move it so the ply dosnt move too. If  you want tape over the join too  give it a finished feel. Any tape will work.  All I ask is to make sure a slat is under /supporting the top and lower  edge of the ply top and bottom.

If the join is under you you will never know as the join is 1mm gap not wide like slats. the matress and you will always be supported.

Side note : Yes   changing from slats to flat really does increase matress performance a worth while project I also have done this and it was a noticable firming matress support change.

To save off cut waste you can put a dozen off cut sections length ways on top of the slats and  the matress and ply will be fully supported as  cut to the bed width and length.

[Lynda2021]

Thank you so much for all your help. I’m comfortable about going forward now. Cheers. 

[TedBear]

Thanks @Lynda2021 for the putting the question and @Jewelleryrescue for suggestions.... I had never thought of doing this, but I will now that you've drawn my attention to the benefits. I have always thought that my mattress could be supporting me better.

[Jewelleryrescue]

Hi @Lynda2021 

I hope you dont mind I was doing some more product research  as how to beest cover your bed slats.

Now I am working off your original full measurments 1850x 1450 and have  reduced timber panel sizes down slightly for easy fitting.

The goal is to get an flat base under all the mattress so there is no uneven spots.

Now I now  recommend  a change from   ply to MDF as it will serve same purpose and cost a lot less and  the finish is smoother so the mattress dosnt have any threads pull moving it around like on rougher ply.   I hope you have  not shopped  yet.

Buy  1 x  6mm MDF Panel Standard 2440 x 1220mm  I/N: 0590055 $32

WE  will cut this up into 4 panels that will cover the bed See the rough diagram  below. The diagram shows the full bed size with the slats over the top lightly nail screw the panels on. I showed the small  panels in the middle they can be on the outside edge it wont make a difference. 

The  next diagram is a cutting guide for Bunnings staff of the 2440 x 1220 panel above. 

Raw material Cutting list

[EricL]

Hello @Lynda2021 

It's wonderful that you've received excellent advice from @Jewelleryrescue. Using MDF Panel Standard 2400mm x 1200mm x 6mm should provide you with adequate support.

Please note that if panels don't fit in your vehicle, there is a delivery service available, or you can hire a trailer if your car has a tow bar. 

If you have any other questions we can help with, please let us know.

Eric