When you’re replacing a concrete driveway or upgrading a dirt one, the task can seem a little daunting; it’s a different kind of work from tearing out and replacing old sheetrock. But if the house you’re flipping has an eyesore of an entrance, it can be a worthwhile investment. And, with the proper preparation, it can be done smoothly, and successfully.
Determine Size and Shape
The first question you need to ask is “Where is the concrete going to go?” If you’re merely replacing an existing driveway, that question has an easy answer. Square or rectangular shapes are easier to install, but depending on the property you may need to plan for something different. Be sure to measure the area of your future driveway, and mark it off (with high-visibility spray paint, for example). Once you have that planned, you’re ready for the next step.
Removal and Excavation
At this point in the process, you’ll need to determine if there are things in the way that need to be removed, the previous concrete slab being the obvious example. If it’s a dirt driveway, or if you’re changing the shape, you may also need to remove things like trees and shrubs. Determine whether you will be using hand tools and elbow grease, or whether you’ll be using mechanized solutions to make this happen. Removing it by hand may save on machine rental and doesn’t require an operator with know-how, but it may cost you extra in man hours. Besides, you may want the larger equipment for use in the excavation process anyway.
This is the point where you will need to determine the depth of your slab, and what you’re using as an underlayer (gravel or crushed rock being the preferred choices). Slab depth in large measure determines its strength—increasing from 4” to 5” makes for a 20% increase in price, but provides a 50% increase in strength. The larger the slab, and the more weight you expect to be on it, the thicker you will want it to be, and the thicker you want it, the deeper you will have to excavate.
Estimate Cost of Materials
You will need a few things in order to build this driveway. First and foremost, you will need the forms for the concrete. Usually built out of 2x4s, 2x6s, or 2x8s, they will have to encompass the entire layout, and be tall enough to accommodate your desired thickness. 2×4 studs typically range anywhere from $4 to $10 depending on quality, with 2x6s costing between $9 and $15. Both are sold in lengths of 8, 10, 12, and 16 feet.
Next is your gravel underlayer. It should be at least 4” deep, though increasing the depth increases strength and durability of the driveway (similar to concrete depth). Gravel is especially important when compensating for severe slope grades or poor soil. Typical pea gravel often costs around $30 a cubic yard. We’ll go over how to calculate that in a bit.
Steel reinforcement is something you’ll want to consider strongly, as it dramatically improves the durability and strength of the concrete. The driveway won’t likely need something as dramatic as a rebar lattice to reinforce it, but steel mesh can still do wonders, and its cost is comparatively minimal.
Finally, you have the concrete itself. You can either have it mixed by hand, or you can have it delivered, which is probably your preferred method for this task. Having it delivered costs, on average, about $90 a cubic yard, plus a delivery fee, and likely the driver’s hourly wage. Cubic yards are calculated by multiplying width by length by depth. You’ll either have to convert the depth to feet (4” = .35’), or the other measurements to inches. For irregularly shaped driveways, the equation gets a little more complicated, but there are some tools available to help you make it easier. You’ll also want to adjust by about 10% to accommodate for spillage and discrepancies in depth.
Plan for Labor Costs
Beyond the price of excavation, removal, and prep work, you’ll also have to pay for the laying of the concrete, the flatwork (“finish work” for concrete slabs), and any cleanup you don’t want to do yourself. On average, labor costs are around $2.40 a square foot for a 4” deep slab, though the price varies by region and quality of the contractor.
Decide What to Do Yourself
You can save a fair amount by committing to do some of the work yourself, but depending on the activity, you may save yourself trouble in the long run by contracting out the work. The layout, excavation, form building, and gravel laying can all be done by someone with reasonable confidence in their DIY abilities, but be warned—the strength of the forms determines whether it breaks or moves under the weight of the concrete, and the gravel needs to be compacted and leveled as best as possible before you begin pouring. As for the pouring and flatwork, typically you will be better off leaving that to professionals.
All-in-all, you’re looking at between $1,000 and $3,000 depending on the size of the driveway. Spend it well, and you will have an impressive value-add (check out Tarek and Christina seminars for more house-flipping tips) to the home’s architecture that will help you sell the property.