Add Bridging Attic Joist

If the attic joists are not adequate one way to strengthen the floor for live loads is to sister the old joists.

Add bridging attic joist. A raised platform of lumber in dimensions of 2 4 or 2 6 with insulation placed between joists and covered up with a 12 inch plywood helps build the right flooring. Then measure the span of the joists the distance between walls or beams that support the joists. House basement is from 1980 ish and i noticed our floor above is flexing when you walk squeaking etc. Fixing joist blocking or add bridging should i joist hang.

Toenail the blocks or end nail through the joists to tie everything together. Put 2x8 blocks at the third points set at the midheight of the assembly and bridging the horizontal joint between top and bottom joists. Add nails or screws if necessary. Sistering is the process of adding a new joist next to each existing joist.

Divide the span by three and add rows of bridging at both of the one third points. Installing flooring material over the attic doesn t quite leave room for the recommended insulation space needed to provide efficient home energy. If the existing joist system is very close to being sufficient to support a new attic flooring the addition of bridging between the joists may be all that s required.