When going through your new home at framing stage, here is an explanation of what you are looking at. I will talk about basements and crawl spaces all the way through the roof and give a brief explanation of some of the methods and materials used in framing today.
Starting in the basement, we will typically use 2x6 studs in the exterior walk out walls, 16 inches on center. Because the house may have one to two floors above it, the 2x6 studs give the exterior walk out walls the extra support that they need to carry the additional load. You will also notice that anytime that wood is touching concrete, whether on top of the foundation walls or on top of the concrete floor, we use treated wood. We have found that treated wood stands up to the rot that can be caused by the moisture that is ever present in concrete and protects the untreated wood that the rest of the home is built out of. In basement houses, we almost always use open web floor trusses for two reasons. One, most, if not all, of the Duct work can be hidden inside the trusses along with the plumbing and wiring. This eliminates the need to frame around the ducting in finished areas of your basement which lowers your ceiling height in those areas of your custom home. Two, Trusses are engineered to make sure that you don’t have a lot of deflection or bounce in the floor above. If we have a load bearing point in the floor above we will install squash blocks either inside the truss or beside it with studs below to bring the load all the way down to the concrete, this helps keep the floor upstairs from sagging over time. Squash blocks are a piece of 2x4 material that span the truss from the subfloor above it to the wall below it to keep the truss from sagging at the low point. If we use floor trusses, we are required to use roof trusses as well, because they are designed to bear on exterior walls or have specific interior load points that can be addressed by the squash blocks and bracing as mentioned. If you want a finished basement, we will use 2x4 studs on 16-inch centers to frame your interior walls. If you want to leave your basement unfinished in your custom home, we will typically only frame the interior bearing walls, leaving the basement open to finish at a later time. The other thing you will notice as you look up into the floor trusses, is the trusses with have 2x6’s within them, connecting one truss to another in certain areas. This adds strength to the trusses, making them act all as one unit, all helping the others carry the load above, strengthening the floor and reducing deflection.
In Southwest Missouri, many of the custom homes we build are built on crawl spaces, in this case, the framing under the first floor is a little different. First, rather than interior load bearing walls like you would have in a basement, the floor joists are built on top of girders between the foundation walls. The girders are made of tripled up 2x8’s or 2x10’s that are spaced between 7 and 10 feet apart with additional girders at any other load point. Most of the time we will not use floor trusses in crawl space homes because we can save money by using more traditional material for joists. Depending on the spacing of the girders and the type of load in the floors above, the joist will either be 2x8, 2x10, or I-Joists. I-Joists are like floor trusses except they have a piece of OSB between the top and bottom 2x4’s making it look like a wooden I-Beam. The advantage to using I-Joists is that they are engineered to have longer spans between supports. Like basements, the floor joists are sitting on top of treated wood at the foundation walls, which protect the untreated wood from rot. In order to strengthen the floor under walls that run parallel with the joists, we will add an extra joist under the wall to make sure it has plenty of support and helps prevent sagging under the walls of your custom home.
The next part of framing process that I will discuss is the floors above grade, or ground level. Whether you have a basement home or a crawlspace home, the next important part of your home is the sub-floor. The two types of subfloor that we use are LP’s Legacy and Huber’s Advantech. Both resist moisture due to rain during the construction process and have fantastic warranties. Your custom home’s exterior walls in the floors above grade are typically framed with 2x4 studs as well as most interior walls. At times we will use 2x6 studs on interior walls if it is a wall that will have plumbing fixtures or if it’s an accent wall at an arch or an art niche. Above windows and doors, you will see 2x10 headers that carry the load above it and prevent sagging above the door and window openings. If there are large openings, such as garage doors or a large bank of windows, we will use engineered beams, which are stronger, and we are able to ensure that they won’t sag with the heavy loads associated with longer spans. Gravity is always working against us, so as we frame your custom home, we always have that in mind and are making sure there is plenty of support holding everything up. Whether your custom home is a basement home or a crawlspace home, we like to use roof trusses whenever possible. Like I mentioned before, roof trusses typically only bear on exterior walls or specific interior points that we can brace all the way down to the ground below the house. This way, we aren’t leaving it up to the framer to potentially brace a stick-built roof down to an unsupported point in the house, causing sagging floors. When looking up at the roof trusses, like floor trusses, you will see 2x4 bracing connecting a lot of the trusses together in places. This adds strength to the roof system, making all the main trusses work together as one unit.
In addition to the things that I have already discussed, as you look around your newly framed custom home, you will notice metal hangers, connectors, bolts, tie downs and many other things that make sure the bones of your new home are strong and will last generations. All in all there are a great many things that go into framing your new custom home and we make sure it is all done right and that we use the newest methods and best practices to ensure we are providing you with the best custom home possible!
By Ryan Green
First Choice Custom Homes