Chasing for cables
Chasing cables is the process of placing a cable into the wall behind the plaster, unfortunately there is no way this can be done without drilling some holes. A ‘chase’ is a channel that is cut into the wall that allows the cable to be hidden by a protective layer and then plastered over. The plastic cover comes in several different sizes, it may be easier to go for a smaller cover on some walls as we found that the red brick walls were extra tough to chase compared to the light grey light duty block work which was easy.
Network/power points should be at the same height and location in all rooms unless it’s in the kitchen or bathroom, I have placed the data points 12 inches (1 foot ) to the side of the main power points and 42cm above the floor. This gives unity throughout your setup. Grab a backbox and the chasing cover, align the cover on the wall where you want to chasing to go and mark a line. Place the backbox in the desired location and using a spirit level mark the hole where the box will be recessed. Start chopping away! we used a large grinder with a mortar disc on to cut the main chasing lines and then tapped the rest out with a chisel. On the red brick walls which were really rally hard (allot of burnt brick which is black when you cut into it) we used the core cutter to get the depth we wanted and then chipped out the remaining circles with a chisel.
Cutting the hole for the back box can be done in 2 ways, chisels and core cutter or just with a chisel. Its easier with the core cutter as you just need to tap out the extra bits and you can mark on the cutter how deep you want to go to save chipping out too much of the wall. It’s a good idea to have a small spirit level to hand so you can place it inside the backbox to make sure you can actually screw the box down level. Once you have screwed in the back box you can start to fill in around the extra space in the hole, don’t fill the hole so it is flush to the existing wall as you will have to sand it down for the final plaster layer that will go down the newly cut chase and then around the socket, it makes it easier to apply the plaster level if there isn’t excess depth around the socket.
The cables are then pulled through the floor or up from the floor and into the chased trunking. You can place the cable in conduit but as we are using a chasing cover I haven’t bothered, it would be squashing the cable and I am not looking to re-pull runs. Always give yourself extra cable then you need so have a good foot if not more if you can afford it laying on the floor from where the wall faceplate sits.
Tack the protective covering down nice and neatly so
that bits don’t get in the way when plastering but make sure the cables aren’t squashed. I will wak a post up on running the cables to the faceplate’s later.
Next job is to fill in the chasing with plaster, this can be abit tricky if you haven’t done any plastering before. It might be an idea to fill in the chase with plaster a little before doing a final finish as the depth might make the plaster droop a little. Have a Google on plastering.
Below are some pics taken just after the second trowel over of some newly skimmed chases, the final trowel still needs to be done.
