Garage Dehumidifier: The Guide

Customer’s asking for a dehumidifier for their garage is a common request, but what type of dehumidifier is best?

If you want a dehumidifier for your garage then you are probably storing something important that needs to be protected.

The top 5 problems

1. Anything paper based will most likely suffer from excess humidity in a garage and will shows signs of mould and dimensional change.

2. Tools made from metal will rust.

3. Classic cars and bikes could well be made from a mix of materials that are vulnerable to damp – leather, metal, wood veneer and cloth for example.

4. Other likely items to need protection in a garage would include tents, wine, biking gear, photos, old records and furniture.

Why do we get these damp problems in our garages?

1. Paper is organic and therefore wants to be in equilibrium with its surroundings.  If the air is damper than the paper then the paper will absorb the moisture which will make the paper grow in size and will encourage mould growth on the paper.

2. The surface of metal tools will be cooler than the air around it, this means that condensation is more likely on metal tools.  When water forms on metal then the iron or steel reacts with the water and oxygen and rust forms.

3. Leather, wood veneer and cloth react to moisture in a similar way to paper in that they like to have the same level of humidity as their surroundings.  As they become damp they will peel and allow mould and fungus to grow.

4. Mould and condensation are the biggest enemies in your garage and can damage any material that you are storing that are organic based.

And of course we live in a damp part of the world.

Is this damaging for our wealth?

Cleaning, maintaining and in the worst case replacing the items that you are storing in the garage could be costly.  In the case of family heirlooms these items cannot be replaced and have to be preserved.  Classic cars and bikes are expensive enough to maintain and with these things prevention is better than cure.

So what is the solution?

Increased ventilation is not really a solution for a garage as you cannot leave windows open without worrying about having a security risk and you are not going to run out to the garage every time it rains to close it.  You also have no way of knowing if the air coming into the garage is damper or drier than the air that is already in the garage.

The solution is to have a well-sealed garage coupled with a dehumidifier to keep the air dry.

Why will a dehumidifier protect my belongings in the garage?

1. A dehumidifier removes the excess moisture from the air which reduces the relative humidity.  If the relative humidity is lower then mould will not form on the paper based material in the garage.

2. A lower relative humidity will mean that condensation should not form on the metal tools and car/bike parts.

3. The classic cars will benefit from the lower humidity in that the mould and fungus will not form on the cloth and leather.  You need a dehumidifier with a humidistat so that you do not over dry the air which could crack the leather and the veneer.

4. The other organic material in the garage will benefit from the lower relative humidity and will now be in the ‘safe zone’ for storage.

Where do I put the dehumidifier?

Somewhere close to a power supply so that you do not have to use an extension lead.  As you are unlikely to be in the garage that often then using a hose for continuous drainage is sensible so that the dehumidifier does not turn off when the bucket is full waiting for you to empty it.  Make sure that the dehumidifier and those things that you are protecting benefit from good air circulation within the garage.

Seal the garage up so that you have as few air changes with outside as possible.

Which dehumidifier should I buy?

The Meaco DD8L Junior  is the obvious choice in Northern Europe because it’s performance is consistent at low temperatures (your garage will be unheated in winter), it has a good humidistat, can be drained continuously, has Auto Restart so it will turn back on after a power cut and has a host of safety features to make sure that it is safe to be left alone.  It also one Best on Test when Sailing Today magazine looked at dehumidifiers for unattended application in 2013.

In warmer climates (+16°C all year round) then the Platinum Range with the built in Auto Restart become the go to models.