I have started packing grout under the metal threshold of the exterior doors that I work on, particularly the patio sliders. I started this because I was bothered by the hollow sound when stepping on the threshold, and I didn’t like the gap. (Let’s don’t get into the issue of proper door installation…most of these situations are encountered during other repair work, such as replacing rotted trim.) Anyway, what I do is mix a batch of quick setting grout and squirt it into place with a mason’s grout bag, then tool the face smooth. Works great. Next day the threshold is solid as a rock. It works so well that I am assuming I have overlooked something, and that it’s not a good idea. Comments?
Replies
Sounds better then a guy I worked with that just shot construction adhesive into the gap
That's what led me to the grout. I used to put down a good bead or three of goop before I set the door, but after it was done I was unhappy with the results. Probably a result of adjusting the door in the opening , not enough goop, too big a gap, or whatever. So now I pressure-grout when the door is completely set. Seems to seal the gap completely with a non-biodegradable material, and fully supports the threshold. Doing it by hand with a grout bag, I don't think I can exert enough pressure to deform the threshold (as opposed to expanding foam).
How does this perform for moisture seal? I'm thinking of doing same, seems like a solid way to support the threshold, but once the grout dries, seems like its the same as a threshold on the slab with no sealant. Maybe caulk the under side of threshold before install, then squeeze in grout after? No one else has had this idea in 20 years?
My concern is the grout wouldn't have a long term bond to the threshold since it's not masonry. Instead I would use a construction sealant. Sika makes a few types, in a variety of colors which bond to a variety of materials. It's like caulk on steroids.
Frankie
The most important step that many folks leave out is to install a sill pan. This trough will prevent any water intrusion and will isolate the framed entry way from moisture contact.