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Rotted Sill

I am residing my house, under one section of the siding we found a badly rotted sill, it is next to a water spicket, it's dry now, but the damage is done.

my question is, I only need to replace about 4 feet of sill, do I still need to worry about jacking the house? Or can I just cut it out and pound in a new section?

note: it is directly below a 7 foot window in our living room.

Re: Rotted Sill

It depends on a few things;

1- how old is the house?
2- what type of siding do you have?
3- what type of framing do you have?
4- is the window original construction or a replacement?
5- what type of window is it?
6- what is the sill made from?

if you are lucky you can replace just the sill. If the sill gods are against you, then you might be looking at removing the window to get at the parts you need to fix. The window, if properly installed, would have the framing around it to enable you to remove the window completely without shoring up the house.

Re: Rotted Sill

one other thing you can try first is to drill a hole all the way through the sill from the exterior to the interior. if the damage was done from the outside with water there's a decent chance that it didn't go all the way through. by drilling through the sill you can tell how deep the damage goes. if 2/3 or more of the sill is solid then you can leave it as is and make sure the exterior side of the sill is protected from further damage. if it is completely damaged then you can respond to houston's response and we can give you a better answer.

Re: Rotted Sill

If it is the sill you will at least need to jack up any joists resting on the section you need to remove. Just jack them enough to allow you to slide out the bad section of sill and slide the new section in.


Re: Rotted Sill

*** thanks for all the responces.

First the sill is rotted all the way through, there is a hole at least 5 inches long on 3 inches high clean through the board.

This sill is parrallel to the floor joists, so nothing is attached to it.

The house was biult in 1979 its a prefab 1 story ranch. The damage is on the front. All the old hard board siding is gone, and 3 sides now have vinyl up. The window is a 4 pane window, the outer two panes have are a crank out style, I believe it is a replacment window. I do not know what type of framing I have.

Re: Rotted Sill

if it has to be replaced, the window is not as issue. the problem with having the joists run parallel to the sill is being able to lift the weight of the exterior walls off of the sill. i'm guessing that the subfloor runs ontop of the sill then over to the top of the first joist. then on top of the subfloor is the 2x4 exterior wall framing. some of how you do this depends on if what i just said is correct or not depending on how your house was framed. being a prefab, i'm guessing i'm correct as the sill probably came attached to the structure when it was put in place. if you just cut out the old sill and pull it out in chunks, the house will settle down enough so that you will never be able to just bang a new 4' piece in there. essentially, you have to remove some of the siding about 6'-8' long and about 6'-8' above the sill. lag a 2x10 or 2x12 into the exposed sheathing into the studs making sure to lag into every stud on the 6'-8' run. then you can jack up the studs from the exterior just enough to get out the old sill and install the new sill. after you do the exterior you'll have to install a 4x6 or larger beam on the inside as close to the foundation as you can get and jack up the subfloor just enough to remove the old and install the new sill. it sounds like alot of work but it's less than a days labor for 2 men. i know you're thinking it's only a 4' length of sill but if it's totally rotten the exterior walls have probably already drooped enough so that you wouldn't be able to just slide a new piece in there.

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