Driveways that hold under the Lake Magdalene oaks

Live oaks, and what roots do to a slab

Most of the streets around the lake went in when the live oaks were young, and those trees are enormous now. Oak roots in sand run shallow and wide, and they head for the damp ground, which is exactly what sits under a driveway. The slab holds moisture, the root follows it, and a few seasons later there is a ridge across the concrete with a crack running the length of it.

Grinding the lip down buys a year or two, and it takes concrete off the top of a slab that was already thin. Cutting every root you find is worse, because a big oak that loses its anchor roots on one side becomes a problem in a summer storm. Usually the honest answer is to take that section out, look at what is actually under there, cut back only what the tree can spare, and rebuild the base before anything new is poured.

We walk the drive before quoting and work out where the roots are running, because that decides where the joints land and whether the new work needs a thicker edge on the tree side. Nobody stops a live oak. What you can do is put the control joints where the slab was going to move anyway, keep the pour off the trunk flare, and give the water a way out, so the next bit of movement shows up as a clean joint instead of a broken corner.

• Root runs traced across the drive before we quote
• Old slab broken out, never poured over
• Base re-compacted where roots left hollows
• Joints cut where the slab wants to move
• Trunk flare kept clear of new concrete

Lake lots and where the rain ends up

The lakes up here sit in the ground rather than behind a seawall, so a lot that backs onto water usually falls the whole way from the house down to the shoreline. That is fine until somebody pours a patio or a pad across the middle of that fall without thinking about it. Then the slab works like a dam, water stacks up behind it during a heavy afternoon storm, and the low side of the yard stays soft for days after the rain quits.

Around the front of the house the problem runs the other way. A driveway that pitches back toward the garage, or a patio poured level with a door threshold, parks water against the slab and the block wall behind it. Enrique wrote about a job where the ground itself was the issue: "Jose responded all my questions and took the time to find a solution to resolve some terrain problems, then water can flow without any problems." Nicola Paille got the same treatment on a barn pad: "Even ensured step downs so water doesn't seep in!"

So we check the fall before anything gets formed, and the pour is planned around where the water has to end up, away from the slab and the wall and out onto open ground instead of into a corner of the lot. On a lake side job that can mean a step down at the door, a cross fall you would never feel underfoot, or a run of concrete stopped short so the ground can take what comes off it.

Sand under the slab, and how it moves

The ground under these neighborhoods is sand over limestone, and the lakes themselves are what happens when that ground settles. Sand drains fast, which is why the yards dry out quickly after a storm, and it also travels whenever water moves through it. A slab is only ever as flat as the material holding it up. Wash a channel through loose fill under a driveway and the concrete has nothing under it in that spot, so it cracks along the hollow and drops.

A lot of the housing here is the older ranch stock: block walls, a long drive out to a carport, a screened slab out back, a walk to the front door. Those slabs were poured thin, often with no steel in them, straight onto whatever sand was sitting there that week. When one of them cracks it is rarely the concrete that failed. Dig a corner up and you generally find a soft pocket, a root, or a low spot the rain has been feeding for years.

That is why the base takes longer than the pour. Soft pockets come out, fill goes back in layers and gets compacted, and the grade is set before anybody orders concrete. Old work comes out too, since demolition and haul off are part of the job, and footings and foundations get the same attention when the work is an addition rather than a replacement. B Vargas had an inspector look at a finished job and wrote that "the inspector confirmed that the work was done with excellent quality concrete and proper drainage."

Getting a price in Lake Magdalene

Call (813) 812-1892 and tell us what you are looking at, or send the form and we will come out and measure the job. The estimate is free and it comes to you in writing, with the demolition and base work priced separately from the pour, so you can see where the money is going. If you would rather keep somebody off the property for now, we can start one online instead. The shop is open Monday through Saturday and closed Sunday, and Lake Magdalene is a short run from the yard in Tampa.