WHat’s the consensus on using MDF for exterior trim. i plan on backpriming everything.
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they make an exterior MDF, I believe its called Medex, there are other brand names as well.
Doug
There is no real exterior rated MDF. Medex has some water resistance, but not enough for any exterior trim work.
This, from SierraPine's website (they make Medex):
Medex is an SCS certified, no-added formaldehyde, moisture resistant MDF panel engineered for interior high moisture areas.
That's my accent on the word "interior."
Why not cedar or redwood? Why not Azek or Primetrim?
Edited 5/2/2005 5:31 pm ET by Gene Davis
If you need sheet stock to cut up into x terior trim then you should use MDO (Medium Density Overlay) its a plywood with a paper facing specificly made for x terior use. Sometimes used for street sighns. Do not use MDF or MDX they are not rated for your needs.
excellent info. thanks very much.
I will just echo what reinvent said. Avoid any MDF product; if you need sheet stock, use MDO -- but you will have to contend with the exposed veneer edges."I would never die for my beliefs because I might be wrong."
-- Bertrand Russell
No.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Try Mira-tec Exterior grade product--if it isn't Mdf treated it is real close- used 5/4 of the stuff around my windows 2 years ago and it hasn't opened the joints and looks like I painted it yester.
cut like mdf and routs too--it is made for outdoors with some sort of epox binder . In any case I have had excellent results with it and it may be worth a search on the web if someone around you carrys it.
Mike" I reject your reality and substitute my own"
Adam Savage---Mythbusters
I found their site it is Miratectrim.com---As suntoad says it is smooth on one side ( my use) and embossed on the other.
It comes preprimed on the face and after I milled it before install I hit the other edges and screwed it around the windows--It is really hard stuff so I didn't have much luck with the nails so I screwed and puttied the holes with auto bondo and I bet ya a buck you can't find them. :-)
Edited 5/4/2005 12:04 am ET by mitremike
Edited 5/4/2005 12:04 am ET by mitremike
I've used MiraTech. I replaced all the fascia boards on the house I'm renovating w/ their 5/4 x 8" stock. It comes pre-primed and stamped with a "cedar" grain. Paints up real nice and looks great. Can't vouch for longevity yet, it's only been up for about 7 months. So far so good (survived two hurricanes).
Around here Mn. it has 2 summer and 2 winters under its belt and it wouldn't look this good now if it was true wood. I have more plans for the back of the house and it is on my list of must have materials despite it's appitite for dulling blades.Hurricanes huh? Florida or maybe Miss.? I would guess that if it can hold up to that and our winters that would be a winner in my book.Mike" I reject your reality and substitute my own"
Adam Savage---Mythbusters