Give me all your PVC trim advice!

[VietGnome]

I'm doing my garage door openings with PVC Jamb and face trim.

On the jambs I'll require a scarf joint since I could only get the jamb trim in 8'

I have 1x 8x8 (RO slightly over) and 2x 10x10.

I cant get any specific PVC trim adhesive locally. I was planning on running a bead of PL premium behind the boards, then fixing them with the proper screws with plugs. And putting some clear or white silicone in the scarf joint and fitting it as tight as possible.

I was also between putting the scarf joints low out out of direct eye sight, or high up and away from water.

Any other recommendations or tips?

Should I fit the face trim as tight as possible, or leave a 1/8" expansion gap and caulk it afterwards?

Thanks!

 

[strutaeng]

Regular plumber's PVC cement for PVC trim works. I've used that before. But the purple primer may be difficult to paint over if using white paints. Probably not an issue with dark paints.

If it was wood trim, I would probably say get the scarf joint up high, away from the water splashing. But for PVC, bottom since it's not affected by moisture. Always position the scarf joint to any water sheds away, not into the jamb.

One drawback is that PVC trim is really flexible, so either chalkline or mark they layout of where the trim should go every foot or so.

 

[VietGnome]

Regular plumber's PVC cement for PVC trim works. I've used that before. But the purple primer may be difficult to paint over if using white paints. Probably not an issue with dark paints.

If it was wood trim, I would probably say get the scarf joint up high, away from the water splashing. But for PVC, bottom since it's not affected by moisture. Always position the scarf joint to any water sheds away, not into the jamb.

One drawback is that PVC trim is really flexible, so either chalkline or mark they layout of where the trim should go every foot or so.

Thanks!

I've considered painting it black, but I think that introduces another host of issues with expansion and what not. So I was thinking just keeping it plain. Ive thought about grabbing the clear standard PVC cement and using that, and just immediately cleaning the face of leaks.

Good call on marking layout. The jambs should fit perfectly flush so shouldn't be an issue, but ill have to mark the reveal for the trim on the face

 

[larry4406]

Azek makes glue for their PVC trim but regular plumbers pvc glue will work (no need for primer).

Use stainless steel nails.

Do not paint a dark color. Anything much darker than white will mean thermal expansion from sun heat absorption. Stuff grows an insane amount.

If dark colors are your thing, go Boral or Hardy cementatious trim.

 

[VietGnome]

Azek makes glue for their PVC trim but regular plumbers pvc glue will work (no need for primer).

Use stainless steel nails.

Do not paint a dark color. Anything much darker than white will mean thermal expansion from sun heat absorption. Stuff grows an insane amount.

If dark colors are your thing, go Boral or Hardy cementatious trim.

Thanks! that's why im not painting, I read it makes it too hard unless you use some non heat absorbing black paint. (Like that's even a thing??)

Youd recommend stainless steel nails over the cortex screws with plugs?


I've ready about the Azek adhesive. I'm in Canada so it's not Azek brand and nobody seems to carry the niche specific adhesive. That's why I'm going with pvc cement.

Edit: would you tight fit the trim going on the face at the **** joints? Or leave expansion gap and caulk?

 

[carlaisle]

Clear PVC primer does exist. Could presumably be ordered in if not available on the local shelf. I generally assemble the moldings on the ground and then install them in one piece. I would not bother with a scarf joint on PVC trim. Another vote for stainless finish nails. White caulk and you're finished.

 

[VietGnome]

Clear PVC primer does exist. Could presumably be ordered in if not available on the local shelf. I generally assemble the moldings on the ground and then install them in one piece. I would not bother with a scarf joint on PVC trim. Another vote for stainless finish nails. White caulk and you're finished.

I already had the cortex screws and plugs so I'm going that route.

Would you just **** joint them? I feel that would look like ****.

I attached a few photos of the one scarf joint I did on the 8x8 and I think it turned out really good considering the size. If im not directly below it I can't see it.

 

[Quickstep192]

Once you cut the board for your joint, the exposed edge will be very porous and shouldn’t need primer. Use heavy bodied clear pvc cement if you can get. I might consider a lap joint instead of a scarf because the glue will make the joint slippery and hard to align.

Mask either side of the joint to protect the surface from squeeze out; otherwise, the cement will etch the surface.

Use stainless steel fasteners!!! You can get white stainless trim nails. Anything else will bleed.

 

[Fav Onefour]

Check around on the PVC boards. We have stuff longer than 8' at multiple big box stores. Full length boards would eliminate a lot of your challenges.
I use PVC quite often on exterior replacement and repairs. My main fastener choice is SS finish screws. Nails are fine and the advice on stainless is good. On thing to keep in mind is that PVC is soft. It's tricky to use small head fasteners to "lay down" the board. I use quick clamps along the board to get it tight before running screws. It may help you even with nails.
I use regular old PVC cement whenever I need to attach pieces. I've done quite a few oddball items that take stress and the bond seems strong.
This is an example.

It is a trailer jack stand block for winter use. (PVC doesn't freeze down or rot like wood blocks.) The sides are scraps from sill boards with ends cut at 45s sit PVC cement fusing. Top and bottom are simple 1/2" PVC smooth boards also held by same method. I did add fasteners on the corners to hold it tight while setting the cement and added reinforcement because of the angled sides and outward pressure.

Again going back to PVC being soft, I added the plywood top to prevent the trailer jack stand wheel from punching through.

I added handles made out of a loop of stainless cable because the PVC is hard to grab when it's covered in snow.

Anyhow, that's not really about trim attachment but it gives you and idea of how well PVC cement can work.

Another tip to help with your project. If you look at the block pictures, you will see the exposed cut edges. PVC board is porous which makes those edges prone to collecting gunk and looking dirty. I soak a rag in acetone and rub the edges that will be left exposed. That helps melt the surface enough to close up the pores. The cut edges will look better over time.

 

[beltfeed]

Do not use nails at all with exposed PVC trim. Cortex makes the best hidden fastener system going for PVC trim. the kit comes with a driver tool that sinks the fastener about 3/16" into the PVC and then you use a plastic tipped hammer to install the white plug in the counterbore that is left after installing the fastener. You will not be able to find the fastener or plug after it's installed, it blends right in. I use these all the time when trimming out garage door openings with PVC. I buy them at Lowes. The best non yellowing PVC I have found is made by a company called Kleer.

https://www.lowes.com/pd/FastenMaster-Cortex-for-Royal-Trim-2-Inches-White-Hidden-Deck-Fastener-1-Linear-feet-75-Pack/5017116921

 

[gahrajmahal]

I wanted small arbors over our two french doors on the south side of our house. We have a large chimney chase, Two foot deep and six feet wide. It is right in the middle of the end of the house. Originally the chimney was covered in T-111 siding like the whole house. It originally was trimmed in a box like fashion with 3” cedar. Our wood peckers loved to chip away at the wood trim. I changed the chimney chase to stucco siding, cut two feet wide. On the outside corner of the chimney i used large radius galvanized roof flashing. I changed all the trim to PVC even though it was south facing. We see 90 deg F routinely in the summer. I wanted dark trim and decided to paint it despite all the recommendations against it. It is a dark grey/brown called espresso. This i did 10 years ago. Last year i replaced the T-111 “Smart Side” siding due to rot with Hardi Board T-111 siding and their stucco siding. The dark colored painted PVC trim and arbors came off easily with the stainless screws i had used. There was no rust that affected the underlying studs and particle board i had replaced orriginally. The arbors were glued together with standard plumbers PVC glue and the complicated assembly was as strong as when i made it. The espresso paint had not made any of it warp or delaminate in any way. I simply unscrewed both arbors as assemblies, repainted and screwed them back into place. Its dark out right now, ill take some photos and edit my post in the future.

The nice part, our wood peckers never peck on our PVC trim!







All PVC trim

 

[VietGnome]

Thanks for all the advice. I am in fact using the cortex fasteners with the plugs. They've been great.

Ref my above post I did pre mask each piece real nice before install. I used regular medium clear pvc cement, no primer.

The next ones are bigger pieces so I like the idea of clamping. Usually I had my wife out holding it in place but I'll probably use clamps as well.

I'm doing the back side 8x8 door first, so hopefully I get it down real nice before I do the front 2 10x10s.

 

[CraigStu]

I just did what you are doing as maintenance on our 7 yr old house. Builder was supposed to use pvc but did standard wood trim. I replaced the brick molding and then covered the boards you are installing new w/ pvc also. I used an air powered brad nailer. Couldn't find SS brads w/o buying 1000 of them so cranked up the nailer power and buried the heads 1/16-1/8" deep. I used a white exterior caulk to glue all the trim in place, fill in my joint in the center of the top trim on a 16ft door opening (that took 3 applications w/ real careful tooling), and fill the brad holes. No paint, just the smooth white surface the trim comes with. I will see how this works out over the coming years but at least it will never need to be painted.

 

[Hank11]

Make 45° miter cuts and joints before you put the trim in place. If you can lay the boards to be joined down on something perfectly flat, you can end up with nearly invisible joints. Put blue painters tape on both pieces to be mitered, cut through the tape. Glue them together, wipe off the excess and remove the tape.

 

[JohnX14]

I agree, look for longer lengths. I also use regular clear pvc cement, and the cortex screws.

Back in 2008 I trimmed my 18 x 10 overhead door with azak and painted it maroon. The dark color didn't expand at all. It was a Sherwin Williams paint that was specifically recommended by Azak.

 

[VietGnome]

Unfortunately longer lengths just isn't an option. Trust me.



Finished one door today and started on the front two.

You can see the scarf joints if you know what youre looking for, and the right angle. But normally, nobody would be the wiser i wouldn't think.

The cortex screws are great. Just expensive as all **** and the bit pops out of the head when trying to set it and it drives me nuts picking $1 Grey screws out of my Grey gravel driveway.

I'm using PL Premium combined with cortex screws to mount it, and clear pvc cement in the joints, with painters tape to protect the face. Seems to work quite well.

I'll continue to update with photos as I do the front.

 

[JohnX14]

I'll believe you on the length limitations, I'm just surprised. I see boxes of those cortex screws laying all over the job sites, and i pick up enough just for my use. I guess I should pick up more. They are headed to the dumpster, anyway, typically. I didn't know the price - never bought them.

 

[VietGnome]

I'll believe you on the length limitations, I'm just surprised. I see boxes of those cortex screws laying all over the job sites, and i pick up enough just for my use. I guess I should pick up more. They are headed to the dumpster, anyway, typically. I didn't know the price - never bought them.

Yeah it's super weird.

Everywhere has longer lengths of 4"-8"

But I needed 10" to rip down to size for my jambs and that's only in 8'. Places had 10' on their site but out of stock, when I asked to order some it was all discontinued.

not sure if a 75pk of screws for $75 is common, or if I'm just getting fisted in my neck of the woods or what, but it's wack