by thedoctor »
Thu Mar 29, 2007 9:16 am
Presumably if this course (and we hope the one above it) are under the DPC if it is to be surrounded by slabs Kevin. The slabs must be at least 150mm (two courses) below DPC. The DPC will take care of any water wanting to rise in the bricks and from the point of view of the visual appearance the same bricks would look better. The regs do not dictate which materials to use in this case, only in foundations. A lot of people prefer to use engineering bricks on a slab for the first two courses under a DPC because of water splashing on them, from slabs, during a rainfall. If you read our project on freeze-thaw action this makes sense, but visually it may not suit you. As long as the water cannot get through the DPC its ok but this is only acceptable in a cavity wall situation. If your conservatory only has a single skin (100mm thick) wall then engineering bricks should be used but we would also question the suitability of such a structure. Take a look at most houses and you will see that the same bricks are used for the two courses of bricks under the DPC as are used above. Its only "In the ground" that different bricks, and blocks, should be used and this is most often on the basis of compressive strength or chemical ground activity rather than just plain damp conditions.
