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Community and Q&A

TruExterior Trim

pico_project | Posted in General Questions on

Have a unique situation on trim that is limiting our options. 

1) It’s going to be narrow (2″) so will need to be ripped.
2) It’s going to be painted a dark color.

These seem to rule out Hardie (won’t rip?) and PVC (LRV is ~7 for the paint color). We planned on using LP but not crazy about OSB – especially with the rips required and the exposed edge.

We can order TruExterior trim and have it here in a week. It seems to have the ability to rip and paint like wood, but be more rot-resistant like PVC. 

Any reason we shouldn’t try it out?

Also… Is it not a good idea to try to put ~2″ trim around a nail flang window? We have a mid-century house so trying to avoid the wider trim (1×4) look that more traditional houses have here. However, not sure if the nail flange will cause an issue with narrower trim and if it’s worth the risk.

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  1. Patrick_OSullivan | | #1

    > Any reason we shouldn’t try it out?

    Seems like a good use case for the product. Some things to note about it:

    - The dust is gnarly. Wear a respirator when cutting.
    - It's brittle. Be careful when handling because long lengths can snap under their own weight.

    1. pico_project | | #2

      One other question I added to the original post... Is it not a good idea to try to put ~2" trim around a nail flang window? We have a mid-century house so trying to avoid the wider trim (1x4) look that more traditional houses have here. However, not sure if the nail flange will cause an issue and if it's worth the risk.

      1. Patrick_OSullivan | | #3

        Narrower trim can make life more difficult because, depending on your WRB and flashing combination, there can be a build up of material in the area of the flange. If you have sheathing "meat" to fasten the trim to outboard of the flange area, you have a more consistent plane to work off of so the trim is where you want it to be.

        Screws that have a reverse thread for adjustment will help. You should also pre-assemble your casing and install as one unit.

        1. pico_project | | #4

          Sheathing is new 1/2" plywood with Siga Mavjest 500 SA over it. Flanges are taped with Siga Fentrim.

          Installing the casing as one unit (pocket screws?) would allow screwing just the outer area (beyond nail flange) into sheathing?

      2. Chris_in_NC | | #6

        Like you mentioned, you can assemble the trim separately as a picture frame and then attach the picture frame over the window, instead of trying to assemble the individual pieces in place against the window flanges. This is often done with trim on put on edge for a deep modern "shadow box" profile (I pay attention to modern trim details, I love that stuff). I've seen specific mentions of pocket screws working very well with TruExterior. And you can bond the joints at miters and corners too.

        I've done some cutting experiments with some offcuts and samples I got from a local supplier, and am debating re-siding our house if I can justify the cost (the plant is 30 miles from me, so it's a local product). The dust is not that bad, and all of the recommendations for PPE said to treat it like wood dust, without the extra precautions for silicosis with fiber cement.
        I actually really like it so far, based on the small amount I've actually done with it.

        Miratec makes 2 inch and 2.5 inch (actual width) trim I think, as maybe another option that wouldn't need to be ripped. People seem to be very polarized in their opinions about it though. I'd say use the TruExterior.

        1. pico_project | | #8

          Does it rip like wood? Our contractor thinks it's too much like Hardie and doesn't want to use it. Wants to use LP instead.

          1. Chris_in_NC | | #9

            It's very different than Hardie, yeah. Almost like lightweight MDF density, and with no grain, etc. It's actually fairly low density. I had no issues with cutting it using not-so-fresh wood blades to experiment. It will slightly dull blades, and it's usually mentioned that people get a separate set of saw blades and router bits that are dedicated just to it.

        2. pico_project | | #10

          Looks like Miratec is only a wood grain finish too. We're looking for smooth. Where would finger-jointed cedar fall in the list of options and in comparison to Boral?

          1. Chris_in_NC | | #11

            Miratec is usually smooth on one side and cedar grain on the other, at least the sizes I've worked with.
            Their FAQ says "MiraTEC trim is reversible in 5/8", 3/4", 1" thicknesses with a woodgrain texture on one side and a smooth surface on the other. Both sides are smooth on 1-1/4" thick MiraTEC trim."

            If you have a local TruExterior supplier, see if they have any samples or short/broken lengths that your contractor can eyeball. I understand the contractor is likely being conservative with new products, but it's a pretty good product.

  2. user-5946022 | | #5

    Hardie makes a true 2.5" x 3/4" trim board which is widely available in my area. They call it batten board trim. They also make a 5/4" (actual 1") by 3.5" trim board in smooth and rustic finishes. There is also probably some product available in the Hardie Artisan line, but good luck figuring out what they make - they seem hell bent on making it as difficult as possible to figure out what they might be selling in the Artisan line - fancy website with little to no detail info on the Hardi trim products. Maybe there are none for Artisan....

    1. pico_project | | #7

      I looked for a 5/4 x 2.5" and couldn't see one. Availability is also an problem. We waited 4 months for our 9 1/4" smooth lap siding and are still waiting on the smooth vented soffit panels from Hardie.

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