MDF for Stair Skirt?

[Floyd Cox]

Should I glue up some boards or can I use MDF? It is going to be painted.
Thanks for the photo Jerry.

[Sam Murdoch]

I think that using MDF for painted trim work is a fine option. You know the limitations around water but other than that it is certainly as durable as any soft wood, more dimensionally stable if properly painted and holds paint better. I would prime all the edges and back prime too before the install then just finish the faces as you would wood.

[George Bokros]

I think for an area that can get some abuse i.e kicked by shoes or vacuuming equipment MDF is to soft. For crown molding that sees no abuse it is fine but close to foot traffic in my opinion is not for MDF.

George

[Floyd Cox]

Thank you Sam.

There will not be any traffic around these George.

I think that using MDF for painted trim work is a fine option. You know the limitations around water but other than that it is certainly as durable as any soft wood, more dimensionally stable if properly painted and holds paint better. I would prime all the edges and back prime too before the install then just finish the faces as you would wood.

[Jerry Miner]

I'm with Sam on this. MDF is pretty tough (harder to ding than a lot of wood species) and stable----as long as it stays DRY. I also recommend priming all raw edges as well as the back. My .02

[Carter Forbes]

I built stairs in homes with prices ranging from $300k to $2.7 million for 20 years. If its paint grade skirting, it is MDF 99.9% of the time. Rarely, birch ply or solid pine might be used. Any home below that price point is guaranteed 100% to be MDF or In some rare cases LDF which is total garbage.

[Yonak Hawkins]

... LDF which is total garbage.

Carter, when you say LDF, are you referring to MDF Ultralight ? In my opinion, MDF Ultralight should never be used anywhere that might get kicked.

[Carter Forbes]

Yes, total garbage. I've never used, it but a friend of mine who did tract homes did. Very poor material for skirt boards. Correction to my original reply saying-99.9%_ Although mdf can be used on most radius work too, even under a final stain grade piece, in extreme cases where radius too tight for mdf, use Masonite. If the radius is too tight for the stain grade outer piece, use lumber core ply and take out the back with a planer. After a few passes, lumber core ply can turn on a dime. Veneer core just snaps.