My husband and I are working on an add on great room built on a slab. Now, we are finding there is some leaking under the walls. How can we fix this before going any further? We have outside of add on completely finished but on the inside it is just a skeleton... no insulation or dry wall yet.

Your wording here is difficult to understand
Is it the walls that the water line is in leaking or the concrete slab/floor which is not a wall?
I assume it's the concrete floor call a plumber and see if he has a tool to find the slab leak or a service that does this so a plumber can fix it
Call a company that does this to the whole floor doesn't have to be ripped up

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Now if this is not a water line problem is the outside wall leaking from rain or it to close to ground snow. Get back please.

Signed 21 Boat

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Concur with 21boat. Does the water come from any plumbing within the cement slab? Does the water come from the outside of the walls? Repost the question.

The water is coming from rain. There are no water lines in the slab as it used to be a patio.

Well this may take a while Who built the outside walls?
What is the grade level out side in relation to the slab height?
Are the gutters up?
Is there an overhang on the great room.
Is the leak by the corner where it attachés in the main house roof line?
What roof style is this flat build up/ flat pitched/ A frame roof?
Can you describe what type of exterior there is. Brick/siding vertical siding clap board sining etc.
A real important issue. If it siding how far does the siding outside come down and over past the slab edge outside?
Answer these awhile.

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Well this may take a while Who built the outside walls? My husband and I built the walls.
What is the grade level out side in relation to the slab height?
Are the gutters up? No gutters yet.
Is there an overhang on the great room. There is an overhang.
Is the leak by the corner where it attachés in the main house roof line? One of the leaks is at the point where it attaches to the main house. The other is under the carport. Since we have added more gravel in the driveway, I guess it is higher than the slab all around.
What roof style is this flat build up/ flat pitched/ A frame roof? A framed that runs opposite to the original A frame roof. It has a gables on each end.
Can you describe what type of exterior there is. Brick/siding vertical siding clap board sining ect.? We now have new vinyl siding around the entire home.
A real important issue. If it siding how far does the siding outside come down and over past the slab edge outside? The siding originally hung about 1" over the slab but we added more gravel to the drive until we could have it paved. Now, the drive is probably higher than the slab by about 1/2".
Answer these awhile.

Signed 21 Boat

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Any suggestions would be greatly appreciated

So lets see what's wrong here
1. No gutters yet so ALL the rain comes down the side of the house and hits the driveway that's to high to the finish slab.
What's wrong with that picture. For now clear some stone and drain out and way from house slab. Get the gutters on to help the driveway situation
Is there fascia trim capping on the overhang board where the gutter is supposed to be? Water can get in there also.
Where the roofs attach to each other is also a large water shed in that corner that's most likely higher than the rest on the drive and that inside corner is even harder to drain away because of grade issues.
So the two big priorities here is trench out and away from slab and get gutters on

Signed 21 Boat

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