Last time, we taught you how to get your new home from an empty building pad to a completed foundation. While we can’t cover absolutely every aspect of each phase of construction, hopefully the high notes we hit give a solid foundational knowledge of how your home is built.
So what’s up now? Let’s get your home framed up.
But first – what comes immediately after the foundation is in place?
Depending on the configuration of your home, you may need waterproofing and perimeter drain tile. While the home we’re showcasing does not need those two elements, well briefly describe them here.
Waterproofing: this is a membrane (either sprayed/rolled on or a specialty product applied to the foundation wall to prevent groundwater from penetrating the concrete wall and entering your basement. (Note: if your home is slab on grade, as ours is here, the waterproofing isn’t required as the foundation wall is not above the height of the finished floor)
Draintile: this is also for conditions in which ground water is diverted away from the inside your home with a pipe that literally wraps around your foundation walls to collect water and discharge it (usually into a sump pit, to the exterior, or both)
The next step is to get your sub slab plumbing (or groundworks) in place. All of the plumbing in a typical home collects into waste pipes that are concealed in your walls and floors. Through the home, they will join into a few larger pipes that usually exit your home in one of two ways: through your basement wall, or below your basement floor.
Through basement wall or Hung Sewer:
If the elevation of the sewer or septic system is higher than the basement floor elevation (there are many more details here than what we’ll cover related to ground cover, slope of pipe, etc.), the sewer pipe will leave through the basement wall. This condition is called a hung sewer and all plumbing above the lowest level of the home will collect into this single pipe to leave the home. If there is plumbing in the lowest level (typically a basement), it will drain under the concrete slab into an ejector pit. This pit has a pump that quite literally discharges sewage vertically through plumbing pipes so that it can join the rest of the sewage leaving the home through the foundation wall.
This is the set up we have on this home and is where all plumbing pipes at the lowest level of the home are underneath the concrete slab and collect to exit the home in one location. The plumbing pipes are sloped continuously towards the exit (the lowest point of all of the pipes) so that sewage flows downhill.
As a reminder, our home here is a slab on grade home. This requires even more plumbing groundworks (all drains in the first floor of the home are placed at this stage) and more planning and precise measurements. All of the pipes need to be measured accurately so that they come up into walls that do not even exist at this stage! When your home is framed on top of the concrete slab, with these pipes in place, they will act as the drains for the plumbing system of your home. In some cases, slab on grade homes also require or warrant the placement of water lines underneath the slab, but here we will be using walls and freeze-protected attic space.
Once all of the plumbing is in place, it is inspected by the local jurisdictions for proper slope, pipe sizes, and more.
After the plumbing has passed inspection (some jurisdictions require joint inspections of plumbing groundworks and slab prep – Baltimore County, Maryland is one), the slab can be prepped for placement. Explained simply, and in most cases (this might vary by region), 4″ of gravel – #57 stone, typically – is placed on the dirt inside of the foundation, covered by plastic sheeting, and rebar or welded wire fabric (for strength) is placed on top. This home required gravel, 2″ of rigid foam, plastic with taped seams, and welded wire fabric.
The majority of the slab will be placed flat and level, with notable exceptions being in garages, where code requires a slope from the rear of the garage toward the garage doors. This is to help with removal of water that may enter the garage.
*Best Practice* – at exterior doors, space the wood form 1-1/2″ away (using a piece of 2x material) from the wall towards the exterior to provide support for the door sill.
After inspection by local authorities, the concrete arrives in trucks and is placed. Concrete placement and finishing is a skill that few have and the construction industry largely recognizes concrete laborers as some of the hardest working tradesmen around. The concrete is placed to the right height and troweled to a finished condition.
In normal weather conditions, concrete will harden relatively quickly and can be finished soon after placement. During colder weather, even with additives mixed into the concrete, it may take several hours before the slab can be finished.
After the concrete slab is placed and finished, it’s time for one of the most exciting phases: framing.
Framing in and of itself could take an entire book, so we will spend our time just on the basics and notable items.
There are so many methods, codes, material differences, preferences, and more that will widely vary how homes are framed from one region to another. Additionally, jurisdictions have specific items they focus on to ensure health and safety, as well as form and function. Some jurisdictions are focused heavily on fire stopping, whereas others are more concerned with the roof trusses and structure. Even others are focused more on making sure the exterior meets design guidelines for the local neighborhood. Point being: find a quality builder (www.jtcustombuilders.com) who knows the requirements and methods to ensure ALL of the above are met for your home – NOT just the items the local authorities will be looking for.
The very first step in framing is to square the framed home on the foundation. Believe it or not, sometimes even the best foundation crews can install a foundation wall that’s not perfectly square. The framing crew will check this and make (hopefully) minor adjustments as they start. Remember the anchor bolts we placed in the top of the foundation wall (see the blog post, here)? The framers will place a sill sealer (often a piece of 1/4″ thick foam) and then the mudsill (or sill plate), which is typically a pressure-treated 2×6. It’s pressure-treated as it’s in constant contact with the concrete which is inherently apt to being damp at times. The mudsill is the bottom of the framed structure and is held in place with the anchor bolts secured in the foundation (there are other methods and hold downs, but we used 1/2″ anchor bolts here).
If the home has a concrete foundation wall basement, there would likely be a beam installed at this stage that supports the first floor joists. Floor joists would be installed on top of the mudsill and the beam and then subflooring material on top of that. For our home here, again since it’s slab on grade, the walls are installed directly on top of the slab with the mudsill acting as the bottom plate of the wall.
Ready for more framing?
Stay tuned for our next installment where we’ll cover more of the framing stage (maybe all?).