How to fix Water in Garage Concrete Floor During Rain?

Answered by LCD: To pin down where this water is coming from, you would have to catch it early in a rain, or look for flowlines on the floor maybe showing where it is coming from. Possible sources:

1) leak in siding so water is running down in wall and out onto slab - solution is find and fix leak

2) buildup of water from direct wall runoff or roof runoff or gutter downspouts which do not carry the water away from the house, so it is leaking through the foundation - fix is to direct outside water awayu from the foundation by proper drainage slope and soil compaction near the house

3) high groundwater or seepage under the strip foundation, which is coming up through the joint between the slab and the foundation wall - solution rarely is waterproofing the joint seam, usually requires you stop the water from building up near the garage, by accelerating drainasge away form the house (so it does not soak in much) or by putting in a french drain and/or surface waterproofing at the outside of the foundation wall

4) above but coming up through the slab - though usually while it might look damp in a few places, but if has free water ponding would almost always be coming up through cracks in the slab.

5) direct rainfall coming through joints in garage door or between the door and the side frame - though water staining on the inside of the door or frame should be obvious in that case. Solution is weatherstripping the joints at the outside edge.

6) direct rainfall on door dropping to slab below it, and then into garage under the door because slab slopes wrong way - in instead of out as it should. A rubber seal strip on the bottom of the door might reduce this if only due to water pooling a bit there, but generally not as well if slab slopes wrong way. If slope is problem, grinding to reslope can be done by a concrete grinding company - or putting in a grouted sill at the door bottom seal to act as a dam can work well provided it goes FULL width of the doorway.

In any of the above - in directing water away from the house, in addition to roof runoff as the most common culprit, a drive sloping to the garage can also do this - commonly requires an interceptor open-top driveway drain or a "speed bump" on the drive itself to divert the water off to the side where it will drain away from the house.

Answered by EssKay: Thank you for your response!

My house has a sloping/raised land behind it. Rain water will come towards the house.

May be we need to divert it away from house as you say...

We will explore different options on how we can take away the water from the house.

Thanks!

Answered by LCD: If you look through previous questions with answers in the Home > Basement Waterproofing link in Browse Projects, at lower left, you will find a number with checklists of things you can do to stop water intrusion into a basement or garage - starting with controlling and getting roof runoff away from the house, which in many cases is all it takes.

Obviously, simpler to handle infiltration with most garages because they generally do not sit more than a couple of feet into the ground. In some cases ditching (at least 5 feet from the foundation to avoid providing a connection to it, and preferably at least 10 feet away in high water table areas or open-work gravels or sands that water flows through easily) will handle it, in others you may have to dig a french drain at about that distance a couple of feet into the ground to provide drainage, or in extreme cases puot a french drain and waterproofing on the outside of the garage wall.

In other cases, especially in tight soil areas or if you use compacted fine soil or concrete or asphalt or plastic pond liner as a liner so the water will flow on the surface without infiltrating too much, you can just build a swale - with a berm or bench on the house side as needed. Be careful in planning that you do not penetrate a relatively impervious surface layear and get down into a free-draining material. And of course be sure you have proper permits as needed - especially before getting into wetlands or floodplains.

In other cases controlling the water inflow to your land is critical, if a concentration is coming in from neighboring lands. Sometimes a simple diversion at the entry point solves it. Again, be careful about diverting natural streams (even if intermittent) or draining wetlands, or dumping the flow where it will damage land or flood a neighbor.

Also, pay attention to irrigation - in some cases just watering too much alongside a house keeps the soil wet so during rains it then gets through or under the foundation.

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