cedar fascias

[Dee Taylor]

I would like some advice from experienced woodworking guys please. I am planning to fit cedar fascias around my windows. My house is timber frame with a stucco exterior. The windows are powder coated alumnium. The fascia size is 10cm wide by 2cm thick.
I am thinking to glue the fascias onto the stucco with 2 types of glue. One a quick grab almost contact adhesive and the other a long term flexible waterproof adhesive. I have thought about mechanical fixings but the stucco is really hard and I am not sure what to use in the way of fixings. That would also necessitate pre-drilling and plugging of holes which would be possible .
What do you think?? I live in New Zealand and our system of building is somewhat similar to yours so I was hoping you might have some good thoughts on this.
Many thanks

[Jerry Miner]

Dee---

I've been a carpenter here in the US for almost 40 years. I have never attached exterior trim with adhesives alone. Not saying it wouldn't work, but I would not be comfortable without some mechanical fasteners.

(I think what you are calling "fascias" we call "casing"---the trim that surrounds a window). Here's the approach I would take:

Pre-drill through the wood and stucco. I'd probably start with one or two holes and drive in a temporary screw or two to make sure nothing shifted while I drilled the rest of the holes. I'd put a pair of screws in a pattern, about every 16" (40 cm) or so.

Remove temporary screws and fill the stucco holes with a good sealant. Drive permanent, stainless-steel screws (wouldn't use anything else on cedar)

If you have good attachment behind the stucco, great. If not, pastic anchors work very well in stucco, but do not over-torque the screws. Don't forget the sealant. Good luck

[Dee Taylor]

Hi Jerry
Thanks for your thoughts on my 'casings'. They are purely decorative, but yes I do want them to be secure. I am a designer but pretty practical too, but not sure what size of ss screws to use. I guess I will have to countersink and then plug the holes in the cedar too??? Not sure what fixing I will find behind the stucco. It is possible that the timber frame around the windows will be in the right place for fixings, but I think it will only be down the one edge due to the window frame location.
Thanks so much for responding to me, it is so good to have advice from people with experience.
Cheers
Dee

[Peter Quinn]

Cedar on stucco + adhesive=rot. I am assuming it rains in New Zealand? The back of the casing will hold moisture, difficult to moisture proof it completely, it wont easily dry out to the stucco side, no easy way to flash the cap back under the existing stucco.....not good. Are these being painted? If so I'd be looking at extruded polyurethane trim, doesn't mind moisture, takes paint well, not much fun to smell when cutting, dust is rotten but it works easy enough. I could see it being attached with an elastometric urethane adhesive, but you will need to achieve some clamping pressure during the cure time, possible with clamps back into the building pulling off the interior casings. If they are not being painted or must be actual wood I'd let them float, use as few fasteners as possible, possibly stand them off the stucco on rubber washers by 2MM or better to allow drainage plane behind the frames. Wood rots...I have proof!

[Dee Taylor]

Mmmm this is a very disturbing comment. I do plan to put drainage grooves in the cedar. The glue will be applied in lines and the glue is waterproof. The casings will not sit that tight on the stucco as it has a stippled effect. Yes it does rain here but we use timer casings a lot around windows, in various sorts of details. Some are painted. The cedar will not be painted that is why I chose cedar as I would like something that will be low maintenance. Cedar is used a lot here in cladding and left to weather to a silver colour.