Timber Joist Ground Floor

Solid timber joist sizes are provided in the bs 8103 3 span tables.

Timber joist ground floor.

Step forward the timber i joist and its cousin the posi joist. True floor joist span calculations can only be made by a structural engineer or contractor. Joists on the ground floor were sometimes a pole pole joist half round joist log joist. The joists must be able to support this dead load.

Hollow floors also known as suspended or timber floors are simply timber joists suspended across and supported by load bearing walls under the floor. A round timber with one flat surface and in barns long joists were sometimes supported on a sleeper a timber not joined to but supporting other beams. The ends of these timber joists are built into or suspended by joist hangers from the external walls of the property. Where the tables do not apply or where there are concentrated loads floor joists should be designed by an engineer in accordance with technical requirement r5.

Ground floor hollow or timber floor. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. Building a wooden floor on top of a dirt floor will lead to eventual rotting of even treated wood though the barrier will delay the onset of this for several years depending on the environmental conditions of the building region. When the sagging joists are level apply a generous bead of construction adhesive to the existing joist.

But it s usually best to run the sister joist over the entire span. Then attach the sister joist using three 16d common nails driven every 16 in. The following table gives details of allowable spans and spacing between joists for the most common timber sizes used in floor construction. Saving you time and money on site.

All the figures are based on normal domestic floor loadings where the floor construction is typically 18 25mm floor boards sheets with up to 12 5mm thick plasterboard and skim underneath. Oneboard structural system that can be laid directly on joists. Creating a vapor barrier only delays the effects of moisture on the wood of the floor. With minimum floor build height.

All of these are known as the dead load. Timber floor joists shall be adequate for the spans and loads and be correctly installed. Consider how you plan to run cables and pipes through your floor void. The system is ideal for both new build and retrofit installations.

Driving 16d common nails in old hard wood is difficult. The weight of the timber floor itself consists of the timber joists the plasterboard ceiling underneath it except for suspended timber ground floors the floorboards and the nails or screws used to fix both of the aforementioned coverings. Timber joists can be drilled out or chipped away with caution but it is not straightforward.