Reddit reviews Dennis 10576/ace U Shape Door Sweep White 1-3/4" To 2-1/2"

I have to first apologize for the delay in getting back with you. I had to run to the airport today to meet my brother home on leave and it ate up the afternoon and evening.

From the picture of the open door it looks like there originally was a threshold in the doorway but that it was a narrow threshold more commonly seen bridging between flooring types inside a house than for use on the exterior door.

It also looks like a real whack job on the wood threshold that abuts the concrete patio. Whoever did that needs to work on the measure twice, cut once method. That caulked gap looks to be about 3/8" and should be filled all the way. I'd caulk the whole thing if it was mine. It looks like the whole board needs to be trimmed by about 3/8" and then put in place to cover the gap at both sides of the door.

The wood piece in the doorway actually looks like the wooden part of an old-style threshold with the bevel on the inside. It just appears to be missing the middle piece that would have spanned the transition to concrete and filled the gap at the bottom of the door. You could make one yourself if you have the tools and nail it in place but you are better off using one of the ready-made thresholds instead.

Anyway, since there is no threshold now you will want to install one. The one that you have linked will serve to close the gap but will probably not be very durable since it only anchors on one side (L-shaped).

I think you need a U-shaped threshold like this one:

U-Shaped Threshold

It can be firmly attached to the outside of the door and can be fit to the floor across the transition pretty easily.

From the picture of the door it looks like your door thickness is 1-1/4" to 1-1/2", or at least it is less than 1-3/4" so it is an older wood exterior door or perhaps an older interior door now used as an exterior door. (Landlords can be pretty stupid like that.)

If your door is thinner than the u-shaped channel then you will want to shim out the door thickness using a strip of wood, plastic, felt, rubber, etc. of the correct thickness so that you have a snug fit. It appears that a good shim could be produced using one or more of the paint stir sticks like you get at Lowe's or Home Depot. I'm pretty sure they give them away so no cost there.

Just place the threshold in position, slide the shim into the channel on the inside of the door and scribe a line with a pencil. Then cut the stir stick into enough pieces of that width to span the width of the door. Glue them in place with wood glue, hot glue, etc. and screw the threshold in position after following the manufacturer's install procedure which should be something like:

Slide the threshold into place on the bottom of the door; Measure the width and mark for the width of the opening; use a hacksaw or metal snips or other tool to cut at the mark; slide threshold onto door bottom and position it so that it is touching the floor all the way across; begin with the center screw and install screws from the center hole to the edge holes keeping the screws centered in the screw slots and the threshold in contact with the floor as you go; tighten screws keeping the threshold in contact with the floor to seal the gap.

Another option in the same style from a different manufacturer:

U-shaped threshold with rubber sweep

Another option if your door is less than 1-3/4" thick is this two-piece unit that fits 1-3/4" to 2-1/8" standard thickness doors but can be cut down to fit a thinner door without requiring you to shim the thickness:

Two-piece threshold

If you don't use the door much you can just put strips of thin felt along the edge of the door all the way around to close any air gap along all the edges and fill the bottom gap with felt pad (excellent at blocking air leaks).

While writing this I see that you may already have a solution. I hope that it works for you but will leave this post as an option for you to consider. Good luck and warmest regards.