Friend looking for a new house in Steiner Ranch (Austin: floor, garage door)

[Joe0109]

I have a friend looking for a new house in Steiiner Ranch. He has selected one house and it has drop-down garage. The Garage floor is about six feet below ground level in the back of the house. He would like to understand potential risks associated with drop down garage. Any comments on this will be great.

[jbiggs]

Originally Posted by Joe0109

I have a friend looking for a new house in Steiiner Ranch. He has selected one house and it has drop-down garage. The Garage floor is about six feet below ground level in the back of the house. He would like to understand potential risks associated with drop down garage. Any comments on this will be great.

Are there three sides of the garage below grade? Is the driveway below grade on both sides?

[Joe0109]

I think so. The builder is saying that the front of the house where garage and drive way is low point of the lot and the back of the house is high point. The back yard seems to be flushed with the house.

[jbiggs]

There are two main issues you want to consider. The first is potential for drainage issues near the garage door. If I understand it correctly when he pulls into his driveway it is similar to driving down a gully, even if the yard on both sides of the driveway are ony slightly higher than the driveway. If this is the case then two things should be there. First off there should be an approximate 2" lip where the garage floor meets the driveway and the garage floor obviously should be higher than the driveway. The driveway should also have a sufficient slope starting at that lip and downward towards the entry point. The concept is if any water does come rolling over the yard edges on either side it needs to go down and away from the garage to prevent from flooding the garage. Also the garage floor itself should have a very slight slope towards the garage door. If any moisture does make it in, even from the vehicle dragging it in then it needs to flow towards and out the door. I would also be very leery if the main garage floor was not equipped with a concrete ledge around the three sides that is at least 2" high. Again to help protect the interior from water.

If the garage has three walls under the surround grade then the soils should have been properly prepared to prevent shifting soils from affecting the walls. Austin does not have a lot of the black clays as do other areas but there are still areas of this shifting and expanding black clay. I would discuss with the builder what steps were taken for this potential. I would also expect those three walls to be poured concrete and not wood. Yes there are wood foundations but Texas has a high propensity for termites and wood foundations, regardless of how well treated, are not exactly a good idea.

Another consideration is prevention of drainage over the driveway sides and close to the home. I'm picturing this again as a tunnel effect coming up the driveway. If sufficient rains occur the water can pour over those edges and be a real nuisance.

Another item of consideration is proper guttering around the home with discharge points far from the home. Roof runoff can add a lot of surface water in a heavy rain.

Other than that not really a lot else to be concerned with.