Maria Luisa Castellanos
So you got your permit. Now what? The 6 Phases of Construction
Updated: 2 days ago
So you got your permit for your building, what happens now? This outline of the phases is for a small building in Coral Gables or surrounding areas of Miami, Florida. Construction in other areas will vary and so will large, multiple-story buildings whose process may be more complex. But if you are thinking of building a one-story building, this will give you an idea of the phases. A two-story building will be similar. It will just have an intermediate floor before the roof.
Normally, assuming that you and your contractor signed a contract already, your contractor will start preparing to start the job. (See my article on hiring a contractor: https://www.unitedarchitectsinc.com/hiring-a-contractor ) If the site size permits, he will often bring a construction trailer and sometimes a storage trailer to set up on-site. He must coordinate with you to make sure that the location is acceptable to you. Then, he will start to produce a schedule for the job and line up all the subcontractors he plans to use. He will clear the site of debris and protect any trees. Once all the subcontractors are on board, they will start sending him the "shop drawings" or "submittals" for him to forward to the architect. This process is a check on whether what the architect and engineer specified is actually what is going to be installed in the job. The contractor will normally send catalog cuts of the items he will be installing and sometimes, actual samples, like in the case of floor tile. Once the process of shop drawing review is finished for initial items that go on the job, such as structural reinforcing steel for the footings or the concrete that is going to be used, we can continue to Phase 2. Sometimes this submittal process continues throughout the construction for items that are to be installed later in the work.
Once the site is cleared, the trenches as dug for the footings, and the plumbers and the civil contractors come in and install all the underground piping. This could be sewer or water lines. Normally, sewer lines are white PVC and water lines are copper, although now the code is allowing PVC for water lines, which I don't like for anyone to use on my projects. Any underground electrical conduits have to be installed as well.
In this phase, the contractor starts placing reinforcing steel for the footings, floor, and any columns. If the design calls for spread footings, he pours those first and then starts putting up a row or two of concrete blocks before pouring the ground floor slab. If the design calls for integral footings he starts pouring concrete for the ground floor slab and footings together. Then, if there will be concrete columns, he needs to start pouring those as well. If the structure is going to be reinforced masonry, then the reinforcing steel has to be brought up from the footings into the cells of the concrete blocks. Later, these pieces of reinforcing will be spliced with more reinforcing to go all the way into the beams or tie-beams above. Any plumbing and electrical that is to be installed in the interior has to be brought up through the concrete floor slab.
Once the concrete or steel columns are in place, it is time to erect the roof, if this is a one-story building. Whether the roof structure is going to be wood, concrete, or steel will determine what happens next. Wood is not normally used in commercial buildings today, although it can. So I will concentrate on concrete and steel.
If we are going to be building concrete block walls, we need to erect the walls all the way to the point where a tie-beam will be placed. A tie-beam is like a cap to the concrete wall. If we are doing a concrete slab roof, we need to pour the concrete slab integral with the tie-beam. This gives amazing structural integrity to the roof and the walls. By pouring concrete as a liquid which then hardens, this connection becomes practically indestructible.
If on the other hand, we are going to build a roof with a steel structure, we may attach the steel trusses to the side of a concrete beam or on top of the concrete beam. This will be shown in the plans that the structural engineer designed. Where a tie-beam is an 8" wide x 12" deep with 2 # 5 bars top and bottom, many structures will require deeper beams with more reinforcing than this. Even though we are using a steel roof structure, the roof itself will actually be reinforced concrete. This will be poured after the steel open-web joists are erected.
If we are doing a two-story building, instead of the roof, we will pour a concrete floor for the 2nd floor. And from there we install the columns for then proceed with the roof as described above.
There may be parts of the structure that have glass storefronts. In this case, it could be that extended storefronts may have intermittent concrete columns. If that is the case, these columns have to be attached to the beam that will hold the concrete roof slab or the steel open-web joists.
Once the concrete roof is finished, the actual roofing material that will waterproof the roof is installed. In Coral Gables and Miami commercial buildings, we often use tapered insulation with lightweight concrete or tapered insulation with a modified bitumen roofing material. Then, the interior space is generally enclosed by installing the storefronts or windows. Exterior doors are installed. At this point, we have finished the building envelope and the building is considered "dried-in".
Now, we can begin to install the interior finishes.
At this point the air-conditioning ducts are installed. Sometimes the A/C units themselves are installed, but often these are not installed until the very end because they are expensive and could be stolen. So the space is prepared for the units, but not actually installed yet.
For partitions, we use metal framing, normally 3-5/8" deep, but they may need to be wider or multiple framing members may need to be used for different items, such as chases. Then, on the framing, we can use drywall as a finish for the walls or partitions. On exterior concrete block walls, we use furring strips and then finish with drywall. Prior to finishing with drywall, the plumbing and electrical are brought up through the floors and into the partitions. For bathrooms that will be tiled, we use a cementitious board as the backing. Then, we install the porcelain tile or other stone finish.
Once the partitions pass inspection, the electrical outlets are finished with covers in the drywall. Interior doors are installed.
For the flooring, we will install tile, carpet, a stone finish, vinyl asbestos tile, or leave it as exposed concrete.
Finally, we will install the ceiling and the lighting that will go in the ceiling. Plumbing fixtures are installed in the bathrooms and all cabinetry is installed. Any other fixed specialty items are installed such as wall sconces.
And finally, the A/C units are installed. Once everything is done, the building is painted. Then, the final Certificate of Occupancy is obtained.
Throughout the entire process, the building department must inspect. If not, the CO will not be obtained at the end.
Although different contractors do things slightly differently, this will give you a general idea of the phases of construction and what happens in each.
If you want to discuss your ideas for a commercial building or a building you intend to buy and expand, feel free to call me a Miami architect, Maria Luisa Castellanos, on my cellphone at 305-439-7898.