MDF or Plywood for fireplace mantel and surround

Ply for me for sure. I’m not a homebuilder, so I’ll defer to the experts below. Good luck!

-- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog

Just finished building my second surround from MDF. Have had no problems with either construction or heat from the FP. Would do it again. Both were paint grade, so finish was not an issue. Primed ‘em with shellac to seal before the paint.
Bill

-- bill@magraphics.us

I just did my fireplace with Frame and Panel Wainscoting and Mantel, I used Ply because I HATE MDF, but in hindsight, MDF might have given a more consistent coat of paint being that Plywood has some inconsistencies in texture. (Yes i did use Cabinet Grade Plywood)

So my next adventure for Wainscoting will probably be with MDF.

if it is going to be painted, I’d go with MDF. as much as I dislike the stuff, if yuou want to go with a sheet product, mdf will allow you to construct without hiding endgrain on the corners, it mills up beautifully with saws and router bits, and it paints evenly. It does not do well with moisture, but stands up to heat very well. one caution, make clean cuts and router well, because it does not sand nearly as well as it mills, you end up with a fuzzy surface, the only solution I have found for this which works really well is to coat with thinned epoxy or shellac, depending on the finish applied over it, let that harden the surface, then sand it again.

plywood is stronger, more moisture resistant, and gives you a grain texture on the surface, but it is more expensive, has nasty edges, even if you get good stuff without any voids, and if you plan on doing any shaping, you will have to paint it many times to cover the alternating grain in those edges. that being said, you could always attatch solid edging to any areas you plan to shape or router, but that’s just more work

Hands down MDF; and (not that it matters in this instance) we often use Medex MDF in wet areas without problems and Medite MDF when it’s specified to be fire retardant..

-- Steve, The Hill Country, TX; www.themillworkguys.com

I’m assuming you’re going to paint this since you mentioned MDF here? Or are you considering MDF/ply for the core, with veneers over the top, then putting a finish over that?

I am still trying to get together my mantel/fireplace surround and built-in bookcases. Hopefully it’ll happen sometime in the next couple of months. I’m going the plywood route, but that’s because I plan on staining everything, as I want to use oak for the grainy look. With that being said, if I were going to have it all painted, I’d go MDF.

-- Jonathan, Denver, CO "Constructive criticism is welcome and valued as it gives me new perspectives and helps me to advance as a woodworker."

I used MDF for the legs and facing, but ply for the mantel shelf, using the theory the shelf would get more wear and tear. The legs were 3-sided boxes with lock miters, nailed from the sides into cleats mounted to the wall. The shelf and facing were similar, then trimmed with molding and painted. Surround and hearth were tiled first, then mantel built in place. Here is the result….

P.S. The manual for my gas fireplace had clearly defined clearances to combustibles including the allowable projection of the shelf at varying heights. You’d behoove yourself to check this for your application. For wood burning fireplaces I believe this is addressed in the various building codes. I definitely noticed the shelf getting warm when the blower was not turned on when the fireplace was running. I personally would absolutely respect any clearance requirements….

Tim

Mdf is perfect for projects which will be painted, and where moisture will not be a problem.

I love the look of woodgrain, and for that reason choose to build mine from Tasmanian Oak.

https://picasaweb.google.com/ausiewood/LandsdaleFireplace#

-- wood4me