When installing any floor covering, in particular a wood floor covering, high spots in concrete can be a real issue. Low spots are a pain as well but dealing with them is far easier. Most of the time simply filling the low spot with a compound is all that’s required. However, high spots in concrete on the other hand can be a scary prospect to deal with. It’s not always cost effective to bring in a silly amount of heavy machinery to do this task. Here we’ll be looking at smaller areas and how you can effectively approach them..
The conventional way of removing high spots in concrete is by means of grinding/concrete planes. However, this type of equipment can be expensive to rent and will require many passes to remove high spots. When the high spots are excessive, 12 mm plus, a fast effective approach can be adopted.
One of the best and cost effective methods we’ve found is by using a grinder with a diamond cutting blade accompanied by a dust extraction hood with vacuum attached. We would simply assess the high spot/s to be removed, set our dust extraction hood to the required depth, and cut cross channels in the concrete at close intervals to create a chequered pattern as illustrated in the pictures.
Once we’ve completed our cuts, we would then use a small breaker drill with masonry chisel and send this through the chequered cuts in the concrete. Due to the close proximity of the cuts, a fracture line is created and large amounts of concrete will be removed in one pass of the breaker.
This will often leave a rather cratered surface which will then require infilling with a suitable compound prior to a final finishing compound layer if required. It may well sound like we’re going round the houses a little with this method, however, the amount of concrete removed equates to a massive time and cost saving. Compared to the extremely tedious and potentially expensive task of using grinding equipment to remove relatively fine layers of concrete at a time, to be able to remove 12 mm plus chunks of concrete in a single pass can seriously speed up preparation time of any flooring project.
I’m not saying this is the only way you should utilize, as sometimes the use of grinding equipment is the better approach. The chequered cut method is simply one that is handy to know and useful for certain projects.© Copyright 2016 Wes, All rights Reserved. Written For: Fitmywoodfloor