Floor slab removal

To install the required depth of insulation to provide a U-value of 0.10 W/m2K, the concrete floor slab was removed which involved breaking the slab up with a pneumatic road drill being careful not to disturb any foundations or structural elements of the existing building. The photograph below shows the initial slab break up and is looking from the kitchen extension into the dining room/front lounge.



  

During excavation it was discovered that there was a step in the wall foundations approx 400 mm below the finished floor surface. This could be an original feature or as the result of underpinning at some time after the house had been built in 1896. This unforeseen step created problems as the thickness of insulation on top of the step could only be half of the designed thickness of 180mm.