Diy Loft Conversion Floor Joists

If you intend to board directly on to the joists instead of having a raise floor then start by placing the first board across the joists.

Diy loft conversion floor joists.

A basic floor system is installed in about 10 stages from preparation to boarding the floor. The strong timbers approx 225mm x 75mm timber are secured to the wall plates brickwork and bolted to the walls. The loft room will also have to be separated by a fire door either at the top or bottom of the new stairs. A new floor system is installed using a frame trimmer joists to support the floor joists that span the width of the loft.

There are many ways of altering roof structures for loft conversions but they all have one common element the ceiling joists will almost certainly be inadequate as floor joists. The rim joist sits vertically on top of the sill plate along the outside of the frame to create a lip for the main floor joists. In the case of 2x6 joists you can pair them up with additional 2x6 joists by nailing them together side by side. Once the joists are in all that remains is the noggins cut.

Trimmer joists form the periphery of the new floor. This allows the board that will butt up to its end to be supported by the joist. If the attic joists are not adequate one way to strengthen the floor for live loads is to sister the old joists. For most jobs 2 in 5 1 cm x 10 in 25 cm boards are an ideal size.

Sistering is the process of adding a new joist next to each existing joist. Cut the first timber to the required length the distance between the two steels and fix either side using jiffy hangers and repeat with the remaining joists. This means that new floor joists are fitted alongside them slightly raised above the ceiling plasterboard to avoid contact with it. You ll use the same size lumber to assemble the rim joists as you will for the main floor joists.

If the board overhangs mark it at the centre of the last joist it crosses and make a straight cut at this point with a jigsaw. Clearing the loft area of all debris insulation struts and temporary boards to expose the ceiling boards.