Second Story Floor Joist Size

View of second story floor joists from below.

Second story floor joist size.

As an amazon associate i earn from qualifying purchases. When determining the floor joist size measure the length of the span. Article may contain affiliate links. The span is the inside dimension from the support on one end to the support on the opposite end.

Dead load weight of structure and fixed loads 10 lbs ft 2. 1 ft 0 3048 m. The walls are std concrete block. Additional support for the floor joists is achieved by nailing the ends of the joists into headers.

When building a house or even a deck it is important to confirm you have the correct joist sizes spans and spacing before you get started. Looking at this table you will see there is a choice in the size of floor joist 2 x 6 2 x 8 2 x 10 or 2 x 12 and there is a choice in the joist spacing 12 16 or 14. Live load is weight of furniture wind snow and more. 1 psf lb f ft 2 47 88 n m 2.

Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor. Section r502 10 of the international residential code states that header joists can be the same size as the floor joists when the header joist span isn t greater than 4 feet but if the header joist span is more than 4 feet you ll need to double the header joist and ensure that it s capable of. This size is no longer acceptable when framing a structure. Thu sep 13 2018.

Once the rim joist is in place which creates a frame around the perimeter of the second story floor you ll install the floor joists which are the same dimension as the rim joist. I want this added floor space 2nd floor to support 23000 lbs of house hold furniture no water fixtures. I have a 20 x 40 x 18 ft rv building basically 800sq ft which i want to add a second floor. Tubs sinks showers or appliances.

Floor joists align with the wall studs which align with the first story floor joists. As well as human traffic. Floor joists installed on second or third or higher levels double as ceiling joists for the level below. But larger is not always better when builders are constructing a home or adding a room addition.

In the past 2x4s or 2x6s were sometimes used as floor joists. See the image below for an example of joists spaced 16 on center 16 o c. In buildings with basements the first level of floor joists serves the same purpose. 2 grade of douglas fir are indicated below.

In the table above the widest floor beam span for 12 of supported floor joists is 14 7 if using a 5 ply 2 x 12. The extra two inches of vertical distance when a floor is framed with 2 x 10 joists rather than 2 x 12s can be quite important for example. So we now have adequately sized floor joists and an adequately sized floor joist beam for our 24 x 13 house. Maximum floor joist span for no.

Our floor joist beam can span a maximum of 13. Floor joist size span and spacing table.