Manhattan's exempt-work list, and a question to ask
Manhattan's list of work exempt from a building permit includes painting, papering, tiling, carpeting, cabinets, countertops and similar finish work, and sidewalks and driveways.
Whatever your project takes in, whether a driveway, a patio behind the house, new steps at a door, a garage floor, a pad for equipment, regrading next to the foundation or a cut through the curb where a driveway meets the street, ask the contractor before anyone mixes concrete whether this particular job needs a permit or another city approval, and if the answer is unclear, put the same question to the city's Risk Reduction office. Ask in particular about any piece of the work that touches the public right-of-way, and who is expected to make that request.
The city's general contractor license
Manhattan sets general contractor license requirements by city ordinance; it accepts Commercial (A), Combination (B) and Residential (C) licenses and requires a passing exam score of at least 75% and commercial general liability insurance of at least $500,000 per occurrence.
Questions for the first meeting
- Does this job call for a City of Manhattan contractor or trade license, and if so, which license do you hold and what is the number?
- Which parts of the job, if any, need a permit or a city approval, and who files for them?
- Can you send proof of liability coverage and workers' compensation before work starts?
- Will your own crew place and finish the concrete, or will part of the work go to someone else?
Begin with where the water should go
Before talking about thickness or finish, decide where rain and meltwater will leave each surface. Stand in the yard during a rain if you can, and watch where water runs off the roof, the downspouts and the lawn. Then ask each contractor to mark on a sketch which direction every slab will fall, roughly how much drop they plan across it, and where the runoff will end up. A patio that tips toward the house, or a walk that holds a puddle at the front door, can be hard to correct once the concrete has set. Ask whether any downspout needs to be extended or moved as part of the job.
Forms, edges and the finished line
The wood or metal forms set the shape and the top height of the slab. Ask how the crew will set them, how they check the height against door thresholds and the garage floor, and whether the slab edges will be thickened. Where a new walk meets an old one, ask how the two will line up, and whether the edge will be tooled round or left square.
Soil, gravel and compaction
What sits underneath carries the load. Ask each bidder:
- How much soil will come out, and where will it go?
- What will you do if the crew finds soft ground, roots, buried debris or a wet spot?
- Which gravel or base material goes in, how deep, and how will it be compacted?
- Who calls for the utility locate before digging starts?
What the ready-mix order should say
Concrete is ordered from a plant to a recipe. Ask what strength the contractor orders for outdoor work, whether the mix will carry entrained air, and what consistency the crew wants on arrival. Ask who has the say if someone wants to add water at the truck, since extra water can make the concrete easier to place and weaker once it hardens. Ask, too, whether any admixtures are planned and what each one does.
Rebar, mesh or fiber
Reinforcement is generally there to help hold the pieces together if a crack opens, rather than to keep cracks from forming. Ask whether the contractor plans rebar, welded wire mesh, fibers in the mix or no reinforcement at all, and why that choice suits the load on this slab. If steel goes in, ask how it will be held at the right depth during the pour rather than lying on the gravel.
Laying out the joints
Concrete shrinks as it dries, and joints give that movement a planned place to crack. Ask for a drawing that shows every control joint and its spacing, how deep the joints will be, and whether they will be tooled into the wet surface or sawn later. Where the slab meets the house, a step or an existing slab, ask whether an isolation joint will separate them.
Surface texture
A broom finish leaves a gritty surface for traction. A smooth troweled surface is easy to sweep but can be slippery when wet. Stamped and colored concrete, and exposed aggregate, change both the look and the upkeep. Ask to see a finished job or a sample before choosing, and ask what cleaning and resealing each finish will call for over the years.
The days after the pour
Concrete can keep gaining strength well after it looks hard. Ask how the crew will cure it, whether with a spray-on compound, wet covers or plastic sheeting, and who keeps that going once they leave. Ask what weather would make them move the pour date, how a fresh slab will be protected on a cold night, and when you can walk on it, roll a mower over it and park a car on it.
Lining up the proposals
Set the written proposals next to each other and look for the same items in each: area and thickness of every surface, removal of the old concrete and hauling, excavation and base, mix strength and air, reinforcement, the joint layout, the slope plan, finish, curing, any permits or city approvals, cleanup, the payment schedule and the written warranty with its exclusions. When one price sits well below the others, ask which of those items it leaves out.