Protecting mdf to use outside: (A guide)

 If you are planning to USE MDF for outside uses. You must protect it to make it last longer in rough conditions like humidity, moisture, and sunlight effects. That’s what we mean “outside”. 

One of the versatile materials, MDF has a range of applications when it comes to furnishings, or applications where we used wood in the past. In this day and age, buying natural wood furniture is a costly option for many homeowners.

You are also probably using MDF just because it’s cheaper, right?

And it’s a no-brainer the MDF sheets are prone to absorb water. The outside weather is not suitable for these sheets. MDF material is actually just a board made by fusing wood fibers together.

Therefore, It is always wise to avoid MDF if you live in a region where rains, humidity, fog, and other weather conditions are the norm for the weather. 

However, even if you have to use MDF for outdoor projects. 

Related: Chipboad vs MDF.

Following some tips might help you increase the durability even if kept outside.

Protecting tips on MDF to use outside

The followiing tips will surely help to some extent to make your MDF furniture last longer even if it’s kept outdoors.

But still, the fact is. The material is moisture-resistant, not waterproof. It means it is still susceptible to swelling and warping if directly exposed to the water, moisture, humidity.

  1. Buy water-resistant MDF. 

If you have to use MDF outdoors for some reason. You should know some certain things.

Use a water-resistant MDF grade- a variant in MDF which is treated in a way so that it can withstand humidity and moisture.

  1. Apply a protective coat.

Applying a protective coating is one of the ways you can make MDF material better resistant to water. 

Like natural woods, MDF can hold finishes very well. Regardless of the finish you use, the surface will adopt it. Still if you want to achieve the best results, use oil-based finishes that are more efficient at resisting water.

  1. Paint the MDF 

A coat of paint can provide you with the good results to keep the MDF furniture outdoors. 

You should use oil based paints. Better yet, ask the supplier to provide you the paints that are designed for outdoor projects. That will be more effective.

  1. Make sure to protect edges

MDF boards have edges, which are not covered by any protective caot. 

If you have just purchased the board, make sure to protect the edges as they are open, a small amount of water can easily penetrate through it. Result in, reducing the strength.

Can mdf be used outdoors?

As a matter of fact, using MDF garden furniture outside is not recommended when it is humid and wet. 

However, even if you choose Moisture Resistant density fibreboards for your exterior doors. 

Their use is limited to moderately humid environments. 

It may be wet or sunny outdoors for a long time, so make sure you tell the seller before buying if you plan on using it outdoors. It might help you choose the best grade, or you may get some useful advice on how to keep it protected.

It is most likely that you will be recommended to use a Moisture Resistant MDF board. Their surfaces do not retain moisture and can be painted without prior preparation as they are smooth. 

All machined edges should be cleared of loose dust. and protruding fibres by sanding with 120 or finer grit paper. 

how to waterproof mdf for outside use

Waterproof MDF can be made by applying a varnish, stain, or high-quality wood sealant. 

You can also paint your project with moisture and moisture-resistant paint. Polyurethane can’t be used on MDF because it doesn’t adhere to the surface.

 To begin, you will need a primer designed for MDF or a latex primer. 

Primer should be applied with a 3/8-inch paint roller, and brushes can be used to reach areas that aren’t otherwise reachable. 

Let the primer dry for six hours.

To seal or paint the space, use a 3/8-inch roller to apply a sealant or water-resistant paint. 

You should paint the corners and edges with a paintbrush. 

Once the paint has dried, you should paint the next layer.

 In step three, you apply your final coat of paint or sealant.

If you want the MDF to be moisture-resistant, give it at least three days of drying time.

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