I'm looking to add a timber frame floor to my integral garage to eliminate the step down from house, through internal door, into garage. The difference in level is approx. 90mm. The current garage floor concrete slab is surrounded by breeze block walls.
I intend to put a dpm onto the slab then create a timber frame with joists at 400mm centres. Frame will sit on floor with some attachment to the breeze block wall. I'll then add insulation and 18mm chipboard which will be screwed.
Am I missing anything and does this all sound good? Do I need an additional Dpm on top of joists before adding chipboard?
Any help appreciated as I'm not convinced about the strength of the combi insulation glued to back of chipboard that you can buy.