# Pouring a Concrete Door Sill



## yourfriend

Thanks to the insight of another, I see a solution here shifting. A kind contributor observed that the brick landing where the bad pour of rapid-set cement ended in an attachment had it spanning a joint from the garage slab making it liable to crack. Makes sense to me.

So, either the the overhanging lip of the aluminum threshold had to act as a drip edge (which it seems inadequately wide for) or something had to be placed atop an upright pour under the aluminum threshold to act as a drip edge/sill. A white oak sill was suggested. It would be sturdy but not maintenance free. Plus, it may be excessively thick and require raising of the header to raise the door, something I'll check on tomorrow.


My first thought was a thick plastic. I looked at Azek but some complained about movement if not secured at intervals. Here, it would be trapped by the aluminum threshold and the concrete pour. Does anyone have a better candidate material that would work in the position under the threshold as a drip edge/sill that would be stable, sturdy, durable and not require maintenance in a thinner thickness than a wooden door sill? A stone slab?


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## yourfriend

I'm now looking at cutting a 1/4" thick aluminum door sill and placing it under the aluminum threshold after I've ground down the ridge underneath which would prevent it from lying flat.

My idea is to affix the sill to the concrete with tapcons and a flexible, waterproof and adhesive polyurethane sealant. 

If I raise the concrete pour mounting the sill, I might be able to cantilever and extend the lip of the sill about .75"-1" into the air over the exterior brick landing. 

The aluminum door threshold should sit level on the sill and join to it with a waterproof, flexible and adhesive sealant polyurethane.

Pictured is an old piece of aluminum door sill showing the approximate position a new piece would occupy in relation to the door, threshold and brick landing. 

Another thought is to rip out the brick landing an replace it either with a new brick structure that is level and angled away from the door or use concrete to do the same.

Comments, thoughts or any suggestions correcting or improving the result here are great.


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## wkearney99

What about removing the threshold, hammering out most of the old concrete and forming up a new one in it's place? As in, go to town with a demo hammer (and eye/ear protection) and get 'enough' of the old one out. Then create a form, mix up a stiff batch of new concrete and carefully make a new one in place. 

But by the time you fight with all that you probably could've pulled the door, had a new threshold made out of stone, installed it and been done.


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## yourfriend

wkearney99 said:


> What about removing the threshold, hammering out most of the old concrete and forming up a new one in it's place? As in, go to town with a demo hammer (and eye/ear protection) and get 'enough' of the old one out. Then create a form, mix up a stiff batch of new concrete and carefully make a new one in place.
> 
> But by the time you fight with all that you probably could've pulled the door, had a new threshold made out of stone, installed it and been done.



I find myself interchanging the terms "sill" and "threshold" because they're new to my thinking. Pulling the aluminum threshold with the weatherstripping seen in the latest picture has not occurred to me. 

My idea was, as you said, demolishing the old cement pour. The next step would be attaching the modified aluminum sill to the top of the new concrete pour under the aluminum threshold. That would extend out over the brick landing or its replacement.

Stone as a sill is something I've thought of. Anything you can tell me about how it might work here as a sill would be welcome. The idea of laying something durable here is great. Certainly, I could grind a flat piece into a slope that would help shed rain. Any type of stone you suggest that would be good for that?

Thanks for your help.


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