Water Leak at Sill Plate

[SprintCC]

My garage is enclosed, but not finished yet. I'm hoping to finish it before this winter. The 1st step is fixing a leak at the Sill Plate. It's not the whole length of the sill plate, just about 3 feet.

The interior is unfinished, no insulation, the exterior is Pennsylvania Field Stone. Actual Stone.

During a very heavy rains water can temporarily pool at this point and find it's way inside. Some of this I'm going to deal with with grading & checking the gutters for clogging.

Grading, etc is all well and good but I don't want have to worry about this once the garage is finished, I want this sealed. I'm going to have a contractor do it due to time limitiations, but I'm not even sure where to start -who does this kind of thing? It's not window, door, siding, it's more general weatherproofing.

Any pointers to help me get started in my search would be appreciated.

Chris
Blue Bell, Pa

 

[Spudland_Dave]

Without pics, impossible to determine what or how this needs to be fixed...If you got a puddle outside and its leaking in...simple solution..exterior grade work needs to be done ASAP.

 

[APEowner]

Usually the sill plate should not me exposed to anything more than wind driven rain. There shouldn't be any way for water to pool up against it. Fixing the grading should fix the issue.

 

[rieferman]

Hey Chris, I'm not far from you... with all this rain lately, it's a good test for things like this.

I'd agree with the above post that grading and proper gutters will resolve these types of issue in many cases.

When foundation walls leak underground and can't be fixed by grading (such as when there's a natural spring underground) external solutions (expose the foundation, waterproof it, backfill it) are often more permanently effective than internal patches. But they're also not cheap.

You'd be amazed at what grading and gutters will do. I'd start there and make a judgment before taking additional steps.

 

[NUTTSGT]

Is the stone exterior and the interior wall studding on the same plane ? If it is I'm guess the water is coming in under the base bedding of mortar for the stone exterior.

 

[theoldwizard1]

During a very heavy rains water can temporarily pool at this point and find it's way inside. Some of this I'm going to deal with with grading & checking the gutters for clogging.

Grading, etc is all well and good ...

No, IT IS NOT !

Fix the grading or whatever is causing the water to pool there.

 

[fourjeepin]

I have a similar issue and didn't know how to tackle it until I watched it come in one day during a heavy rain. A trench drain is in my future. Grading may work for you, but my issue is water flowing down the driveway from the main house to my shop. There is a slight slope which carries away most, but not all, of the water. This wasn't an issue for the previous owner as it only occurs a few times a year and it was a carport then.

 

[M17715]

I thought the sill plate was what the top of the foundation was called. So if it is leaking there, like the others said, you need to grade the dirt lower so it is not so high. There should be at least 8" between the bottom of the house siding and the dirt. So the sill plate should be even higher than that. This is not only for water protection, but also to help keep insects, such as termites from getting up into the house. So, it sounds like you need to grade the earth away from the house more.

 

[blkhonda1991]

this is how it should look, typically your foundaiton wall extends up above the slab atleast 8" as garage is right on grade or you pour your slab over the wall to get the plate off grade

 

[theoldwizard1]

During a very heavy rains water can temporarily pool at this point and find it's way inside. Some of this I'm going to deal with with grading & checking the gutters for clogging.

Grading, etc is all well and good ...

I have a similar issue and didn't know how to tackle it until I watched it come in one day during a heavy rain. A trench drain is in my future.

If you want to improve drainage AWAY from structure, but really can not change the elevation at the structure, make a French drain. Dig a trench along the foundation, at least 1 shovel wide, starting at the structure and then moving toward a lower elevation. The trench can start out only about a foot deep, but needs to get deeper as you move away.

Line the trench with landscape cloth and just enough 3/4" crush stone for leveling. I use the white 4" drainage pipe (not DWV) with holes in it. Wrap the pipe in landscape cloth or use a sock. When you lay it in the trench make sure you have enough pitch that the water will run away from the structure.

Cover with 3/4" crushed stone to within 6" of the grade. Fold in the landscape fabric, cover with top soil and sod.

The pipe can come to the surface in a lower part of the yard. If you don't have a place for excess runoff to collect, you will have to dig a dry well.

This works even in low spots that pond after a heavy rain because the water seeps into the space between the crushed stone. This area acts like a holding tank but also speeds up the absolution of water into the soil.

My garage had so much water coming in under the sill for so long that sill rotted out. BEEN THERE, DONE THAT, GOT THE T-SHIRT !

 

[Mr. 360]

I agree with Theoldwizard. I have the exact same issue with my garage, as there is no eaves trough and the earth outside was graded about an inch above the sill (sitting against the wooden siding!). I have been digging a trench along the sides of the building, planning about 12” out and 12” down, with a slope toward the front of the garage where the ground is lower. The cheapest way I can figure, with a bit of your own labour, would be to dig this trench and lay a perforated o-pipe along the bottom to direct the runoff. My quick sketch shows my plan

View media item 31544
(the cross section a few posts up is better, but my yard does not slope away that much, nor is the pad poured above grade)