Timber Upper Floor Construction Details

The ends of these timber joists are built into or suspended by joist hangers from the external walls of the property.

Timber upper floor construction details.

6 4 10 construction of timber floors upper floors shall be constructed in a workmanlike manner and provide satisfactory performance. 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. These are basically timber rsjs rolled steel joists with an i shaped cross section comprising top and bottom flanges made of softwood or lvt laminated veneer timber bonded to a tall vertical web of osb oriented strand board or a similar engineered board. A neat alternative with a timber joisted floor is to put 50mm timber battens on top of your floor deck at 400mm centres lay your underfloor heating pipes between the battens clip them to the deck and then cover with a lean mix screed.

Today the upper floors in most new homes are built using factory made timber i joists also known as i beams. You can then fit a thin plywood layer over the top to regulate your final floor finish. Single joist timber floor is the easiest kind used for residential buildings whereas spans are short or moderate about 4 m and loads are comparatively lighter. The floor consists of wooden joists spaced 30 to 40 cm apart and supported on end walls over that timber boarding or planking is fixed.

The following table gives details of allowable spans and spacing between joists for the most common timber sizes used in floor construction.