Plywood on top of concrete for long term parking

[mo-mon]

Would parking on wood be preferable than concrete for long term parking of our 911's?

The other day I saw a friend who had his Ferrari parking on top of plywood in his concrete garage. I asked him why he did this & he said it would stabilize the humidity under his car. Thoughts?

P.S. I already bought 4 4'x8' sheets of marine plywood

[aus911]

Hi
Depending what you mean by long term parking I have experienced the tyres going out of round.
It may be best to put the car on blocks... Just a thought.
My car gets driven about once every 2 months now, I park it on epoxied concrete, I have done for years without issues.
What I have experienced was I used to store my car in air conditioning, it dried everything out. After that I had to replace most fuel lines etc due to cracking. It may have not been the aircon....who knows. the leather also took a LOT of conditioner and is still very hard, I need new covers...
I hope this helps
Cheers
Ray

[70SATMan]

Originally Posted by mo-mon

Would parking on wood be preferable than concrete for long term parking of our 911's?

The other day I saw a friend who had his Ferrari parking on top of plywood in his concrete garage. I asked him why he did this & he said it would stabilize the humidity under his car. Thoughts?

P.S. I already bought 4 4'x8' sheets of marine plywood

Depends if his concrete floor has a moisture barrier (age of construction).

Does your concrete have a moisture barrier? If you’re super paranoid about your car, Rather than using plywood, I would recommend using horse stall mat. Thick, extremely durable rubber. Wood absorbs moisture doncha know..

[veleno]

How about storing inside a capsule?

CarCapsule - Discover The Original Car Bubble

[Geronimo '74]

Ventilate

[88911coupe]

I thought I'd seen some rubber/foam pads that are specifically designed for long term auto storage. They are not flat, slightly curved, so tires not resting on a hard flat surface.

[Showdown]

Plywood will hold moisture just as well as concrete, in fact the wood will be quicker to absorb ambient moisture, though it will also lose that moisture faster.

You could lay down a rubber roofing membrane if moisture is a concern but that would trap the moisture in the concrete and that will shorten the life of the concrete- not radically but still.

The best thing would be a matrix that allows airflow laid down on the concrete and then a moisture barrier atop that.

The simplest thing may just be to install some sort of air circulation under the car so that moist air is removed from that space. An array of computer fans would do the trick. Just a bit of airflow makes a huge difference.

[AG81]

Originally Posted by 88911coupe

I thought I'd seen some rubber/foam pads that are specifically designed for long term auto storage. They are not flat, slightly curved, so tires not resting on a hard flat surface.

If I understand the OP's question whether wood is preferable to concrete are we talking about only for stabilizing the humidity? I'm sorry I've been dealing with water intrusion and humidity control in homes and buildings for 40+ years and have never heard of such a thing.

Concrete sweats, sometimes with or without a vapor barrier. Concrete also hydrates for many years and in some cases becomes harder. Wood will absorb moisture and can retain that moisture for a long time. In many cases excess moisture will cause mold. I believe the National Plywood Assoc recommends less than 19% moisture. You can take a moisture meter with you to Home Depot and pick a random piece of plywood. Most likely it will show between 10% and 17% moisture content.

If you want to stabilize humidity I suggest you invest in a quality dehumidifier.

If you want to prevent flat spotting on tires I suggest you drive your car or invest in some mats that are designed for that specific purpose.

[Hnichols]

How about 4 mil plastic sheet? I put my cars onto that for winter storage. Don't know whether it's better or worse than plywood or, for that matter, whether it works for really long term storage.

I also inflate the tires to 40psi and occasionally will roll the car forward or backward a couple of feet. Again, might not be a solution for really long term storage.

[Mark Salvetti]

Maybe overthinking this? I can't imagine this makes a huge difference. To me the secret is to prevent condensation.

I'm always careful not to leave the garage doors open when it is humid outside and the garage is much colder. Usually an issue in the spring. It's not just the car, but also condensation causing rusting of tools.

My garage floor is not sealed and I have no idea if there is a vapor barrier. I don't think so. Haven't seen any issues under my car in 20+ years.

I think the vapor barrier is a bigger issue if it's a dirt floor.

Mark

[IS300]

Drive it !!!!

[Bill5900]

I think inflating the tires to at least 40 psi is optimum to help with the out of round thing. Tires will âge whether you drive them or not. Those who make the point about humidity are on the right track. You might inquire on the professional storage garages to see what they do. 50 years ago people recommended removing the battery (probably still right) and placing it on wood instead of concrete. Can’t remember why because it was 50 years ago.

[porsche930dude]

Id say it couldnt hurt but I dont think it will help all that much because the wet concrete will still be all around it. My car is in a garage with a wood floor and it stays very dry while my other garage gets soaking wet If the doors are open in the same conditions.

[70SATMan]

https://canadamats.ca/collections/horse-stall-mats/products/re-vulcanized-rubber-stall-mats-straight-edge

This is what I have under my car, currently up on stands. My house was built in '61. No moisture barrier under the concrete. The mat is 1" thick, pretty much indestructible, takes the weight of my car on the stands and allows my jack use, no problem. Takes a pounding, dropped tools aren't messed up, actually comfortable to be on if I'm working underneath. Spills are nothing burgers and essentially any moisture that would want to emanate from below the car can't. That leaves ambient humidity which neither my mat nor plywood laid on the concrete would address.