MDF also needs to be primed---primer has two jobs---sealing and providing a surface to which paint will easily adhere. Besides, if you just paint MDF, the first coat will be absorbed so much a second coat is necessary.

It is true the MDF will dent more easily---but, how many times does the base molding get hit? Vacuuming? Takes a really hard hit to make a dent.

The edges of MDF will break off more easily than solid wood---but if you are careful, that is not a problem.

Get the MDF and use the savings for something else.

MDF is fine for "untouchables" like ceiling mouldings and window casings. Not so great for baseboards or door casings that get knocked into often.

Watch for outside corners with MDF also.
The corner will not stay 'sharp' through very many bumps.

I don't think the OP is talking about unprimed MDF. Most, if not all MDF that is sold retail is lacquer primed on the face. I also recommend a prime on the back and edge surfaces, even when using soft pine woods.

Michael

I usually stay away from MDF, the only exception for me is when installing crown moulding on the cieling, its easier and faster to work with.

I dont like using MDF because
1)the nailholes mushroom when nailing the baseboard to the wall and painters usually wont take the time to sand down the high areas on every nail hole, and I dont blame them.

But as a homeowner you can take your time and sand down the high areas.

2) the miters tend to get damaged easier when accidentaly kicked or ran into with something.

We used all MDF (baseboards, door and window casings, crown, etc.) when we remodeled 5 years ago. I have had no problems and that's with a maid who thinks the vacuum is a formula one car. I put a good part of the molding in myself and never had any problems with nail holes bulging. Since MDF has no grain, it has a "smoother" finish when painted. I would go with the MDF and save the money. In the unlikely event of a chip or dent, you can repair it with patching compound just like you would do on drywall. We did use wood baseboards in the bathrooms, because if moisture gets into the MDF it will swell - although if it's primed and painted on all surfaces there shouldn't be a problem.

I think the MDF will do well in AZ.

Thanks everyone for taking the time to educate me. It ended up being a split decision. Mom read all the replies and decided to do pine, I decided to do MDF in my house. However, I've decided that when I win the lottery and do a custom house, I'm going to have custom 8-10" baseboards. Her 6" pine is looking more impressive than my 5" MDF (the biggest Lowe's stocks here). Thanks again and happy remodeling..... do you ever get done?

MDF baseboard comes in sizes much larger than 5". Just go to a lumberyard or molding supply (if your area has one).

MDF - Much Disdain of Formaldehyde

Anyway, you may want to consider the toxic implications when installing materials into your living spaces or work spaces. Chemical (unnatural) off-gassing from the likes of MDF, synthetic carpeting, glued down flooring, paints all contribute to toxic air.

What are the major contributors to cancers? It is suspected that the carcinogens in the atmosphere are playing a big role. So, why breath this stuff when there are alternatives with zero or low levels?

Be smart about what you install in your home. Maybe pine with a non toxic, no VOC paint would not pollute your air to the level of the alternates.

MDF is FAR better than real wood. Its flatter, consistent, cuts easier, doesn't splinter or fray, miters are more defined, no grain, If worried about dents, dings, it's best to buy extra MDF, or not live like an animal. Paint all 4 sides of MDF like manufacturers suggest and it will be MORE water resistant than wood. MDF saves trees, the environment, etc. If worried about "formaldehyde", I'm certain you only buy used cars 2 years older, well past that "new car smell"?! The generations that grew up with lead paint and asbestos have far fewer allegies, lower cancer rates, and the rarely seen today, common sense.

B B, you do realize you dug up a SIX year old post.................

John Smith and millworkman do you realize YOU commented on a 6 year old post? Ha! I liked BB's post and it was helpful. (=

I just came across this thread by googling "mdf vs wood baseboard". Behold the power of Google! I am building in a very dry area so apart from bathrooms, no worry about humidity. I will go with MDF and wood in the baths.

As both MDF and real wood base are still available, all comments past and present will be helpful to anyone researching their options!

MDF - painted gloss white. Ours is now 11 years old now and still looks brand new. We used 6" wide. (And yes, even old threads can be very helpful. The power of Google :)

Just the info I needed. We are going to install white base boards soon. Will go with MDF and paint them gloss white. Thanks!

Yes, I am bumping a super old thread again but this seems like a good place to ask my question.

For the people that have used MDF and been happy with it, I'm curious what the profile of your baseboards is? I want to use MDF baseboards with sharp corners and in another thread I was advised this is not advisable. But I know there were several people here who had long term satisfaction with MDF so I'm wondering what your baseboards look like. This is a photo of the base that I want.

MDF is made by gluing wood fibers together under pressure. That means there are two problems inherent with MDF. One, the product is absorbs water quite readily and subsequently expands. Then it easily crumbles after drying.

The second is that the material easily chips or flakes when hit, especially on sharp or square edges.

I refused to use MDF baseboard, chair rail, or door/window trim material. I had less problem using MDF for crown molding.

You will be fine with MDF, most new homes in Southern California and Nevada have MDF throughout, with little to no problems. The same water absortion happens in wood products too. If the base is painted all 4 sides like manufacturers suggest, it will last for decades. Real wood splinters and frays. Sometimes the grain raises. It is never as smooth and consistent.

After talking to a number of people I became convinced that this MDF baseboard is fine with the sharp corner. So many people pointed out that with a sharp corner, a strong enough force that would damage MDF would likely damage wood as well.

Plus numerous other issues with getting the look I want with a wood trim compared to a primed MDF product. However, I may end up using a different profile, but whatever I use, it will be MDF and I am certain it is the right choice.

I currently have 8' MDF trim sitting on the saw horses with the 2nd coat of white paint. 3 down, 12 more to go. :) My only concern is the hallway corners. But easy enough to replace if need be.

I thought it was worth saving $ on baseboards using MDF but it was huge mistake. We have stained concrete throughout house. So even from mopping they have swelled & now look horrible. Water that gets on them in bathroom beside tub or shower & they also swell. The vacuum will hit corners & they look worn. Invest In real wood & save yourself a lot of headache & $ down the road. We are still in process of fixing it. Also a great idea for bathrooms is tile base boards then u don't have to worry if they get wet.

MDF has only one advantage: it's cheaper. Easily spotted in an existing home by the wavy baseboards. If I were a subdivision builder or had a stake in the industry, I'm sure I'd shout to the world that it's "FAR better than real wood."

I was searching for how much linear expansion differed between FJP and MDF and here I am on an old thread and a different subject. I am replacing all the baseboards in my condo. I bought plain 4-1/2" x 1/2" FJP. I later found some of my walls flare out at the bottom as much as 3/16" - even after shimming for carpet or raising the surface with hardwood. For them to fit square against the wall with no gap at the top I had to remove that much stock from the back. I suppose you could use a belt sander and a good respirator but my Stanley No. 4 plane sliced through that like butter. I also like the way the wood grain shows through the painted surface.

Wavy baseboards are from wavy walls and floors.. MDF has better flexibility to mask small deviations. MDF will cope much easier and cleaner, the proper way to do inside corners. Builders use MDF because they want their new homes to look new and modern, and it's a bonus MDF is cheaper, flatter, smoother. Add the cost of considerably more expensive sawblade, more time to fill more needed nail holes to secure warped pine, and triple the time it takes to cope corners. Mitering inside corners is rookie nonsense. If and when wood shrinks, even on a perfect tight miter, thr shrinkage is 2x that of coped corners. Any situation that wood damage MDF would also damage real wood. If doing a remodel and want to rruse the base, lot better chance of clean removal with MDG. / I stand behind my misinformation as firmly as anyone else.

I'll resurrect an old thread to provide perspective from 12 years later.

The house I'm referring to is located in north west Mississippi so it does get moderately humid here - inside is usually 50%-60% RH during the summer.

I built our house 12 years ago and used 5 1/4" MDF baseboard identical in profile to what you'd find at lowes/homedepot. I did not have them paint all sides (probably should have). In the wet areas near the shower and tubs, I should have used wood - I'm not sure if painting/priming all sides would have made any difference. When water gets behind or under MDF baseboards, they will eventually blister, bubble, and crumble.

The base 'cap' was integrated (very common) on ours and seems to be less tolerant of bumps and bruises than I'd expect wood to be. Our house is high traffic with lots of kids and there is one narrow hallway where several pieces of the "ridge" on the base cap have chipped off.

The painters I used were good not great. They used a Sherwin Williams product for the trim which I believe is supposed to be a 'fast coat' and from what I can tell, they did one coat. I repainted all the baseboards in prep for selling with the ProClassic and I can tell the difference - they look much better. The painters also did a terrible job of sanding the nail holes - lots of tiny bumps where the nails are. Had I known/seen it, I would have made them re-do it.

That said.. after 12 years, we are relocating and it wasn't hard to touch things up.

I wouldn't hesitate to use MDF again, but I learned a few lessons:

- Allow MDF to acclimate to the room (they did this on mine)

- Prime the back/sides that are not already primed

- Glue all outside mitered edges

- Proper touch up on filling nail holes

- Sand well before painting

- Use a high quality finish and take your time doing it

- Use wood in areas prone to heavy moisture like bathrooms.

So glad this old post was resurrected. For those of you with cats..... If the cat decides to stop using the litter box and go in the corners of your house, beware of MDF. I have to replace MDF baseboards in two rooms of my house because of stubborn cats. Cats have been retrained and I am trying to decide on vinyl or wood. It is really gross what the cats did to my baseboards. ugh

I just told the floor company to return the MDF baseboards that they brought assuming I wouldnt mind or notice. Formaldehyde is a big sticking point for me. One thing that I also noticed during some recent hotel stays for work - all of the molding and baseboards that look expensive are blistering and coming apart near the floors because when they mop/clean the floors the MDF soaks it up and/or have been damaged badly. Wood isn't bulletproof, but you can buy some great sustainably sourced solid wood for baseboards if your budget allows for it. Here in California we pay an extra tax on wood as well, but for me it is worth it knowing that it won't blister or crumble and there will be no offgassing of formaldehyde.

Update for you google researchers: I decided to replace my cat ruined MDF baseboards with vinyl baseboards in one area of my house. I put wood baseboards in another room that became a bedroom but only because I was not sure of how the vinyl would look. Well, the vinyl looks awesome! We painted it and I can’t tell the difference between wood, vinyl or MDF... it was, however, a bit more expensive than wood. I also replaced carpeting with a waterproof flooring on the third floor and Caribbean pine on second floor. The cats have behaved but even if they don’t I can wipe anything clean now.