Wood Versus MDF for Painted Cabinet Doors

MDF doors avoid the moisture-related movement and paint cracking issues of solid wood. March 26, 2009

Question
My customer wants a flat panel door style with an applied molding and the doors and cabinets will be painted. He perceives solid wood with reverse raise to be higher quality than a "thick" MDF panel for the reverse raise. The doormaker thinks MDF is better because of wood movement issues with regards to paint. Has anyone had a bad experience with the paint line on a solid wood painted flat panel?

Forum Responses
(Cabinetmaking Forum)
From contributor J:
I had one a few years back for one of those insistent know it all customers. They demanded wood panels on painted doors. I use Spaceballs when I build doors. Every door in the house has a crack in the finish where the panel meets the frame. I made a new door to replace one his kids hung off of, with MDF panel for the kitchen. He had his finisher prime and paint it. Only way to tell it's not original to the project is the absence of the crack around the frame. For this application MDF is superior even for the moisture fanatics – it’s flatter, more stable doors and a better finish.

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From contributor P:
The previous post is dead on. You have to use MDF. You just need to explain the benefits to your customer. If he knew more than you or the door maker he would be a cabinet maker. Most people still think MDF or particle board is garbage but it has its uses and benefits over real wood. If they have any raised panel interior doors tell them to go look at everyone. I’m sure they will find at least one spot where the panel shrunk and you see exposed wood.

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From contributor L:
Wood will always show crack lines sometime in the future. If he likes that as a decorative "quality" touch, fine. But he needs to understand that's what it will be. MDF can give a very nice painted door.

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From contributor A:
This is the perfect time of year to show this to your customer. Unless a house is severely humidified in the winter all interior panel doors show panel movement. We get 95% of our heat from a woodstove in our house. Our pine interior 6 panel doors have shrunk almost an 1/8" in our bathroom. Yes, the paint has cracked. It has been our experience in the last 20 years that plywood or even better MDF is the ideal panel for interior cabinet paint grade doors. We have always glued them into the stiles and rails. We’ve never had them blowup. We are talking 20 years not last year. At the end of the day, explain that the wood will definitely crack more, but you will build them with wood if they want it.

I built a vanity in that same bathroom last year. The doors are painted soft maple with glued in MDF panels. I cut a vent in the toe kick for the forced air. I forgot to lower the air volume and I pretty much cooked that cabinet. The plywood interior was hot. These doors shrank quite a bit, but absolutely no cracking whatsoever. They were painted with BIN primer and Muralo Ultra topcoat.

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From contributor R:
I've used both wood and MDF and have had plywood veneers bubble and crack at tiny bubbles, which probably wouldn't have been noticeable in a natural finish but was awful under paint. I fixed it by covering the panels with vertical grade laminate and repainting – in the house yuck.

That being said people don't keep their cabinets dry, especially around the sink, locally aggravated by a humid marine environment. MDF puffs when it gets damp and doesn't shrink back when it dries out leaving a raised checked area like cauliflower. I have tried oil based primers, stain blocking primers, lacquer (automotive and catalyzed) primers and polyester primers with a minimum of two topcoats of alkyd or catalyzed lacquer. I can tell you which work is the nicest but every one of them fail to seal moisture away from the MDF if the user doesn’t keep it dry.