When sanding and sealing parquet block flooring it is important to fill in any small or large gaps in between the parquet blocks. A well laid parquet floor shouldn’t need gap filling, but if the floor is old or has been subject to movement or humidity change, the chances are that the parquet blocks will have expanded and contracted, leaving gaps. If this is the case then it’s a must that the gaps get filled. The best and most efficient way of filling gaps in between parquet blocks is to use a resin or water based filler with the fine dust that is sanded off of the wooden floor when sanding. The finer the dust the better the filler will be. Preferably using the finest dust you can either from a 80 grit sanding belt of better still, the dust from a fine grit edging disk on the edging sander when sanding the edges.
Once you have reached the stage of fine sanding and are ready to start gap filling you should get a small bucket and add the clean fine dust to it. Once you have half a bucket of clean fine dust, begin adding the resin filler to it and mix thoroughly until all the dust has been mixed in completely and to a texture of a custard paste. Remember to make sure that the mixture is mixed correctly as if there is any dust balls, then they will not look very good when troweled into the gaps!
Now it is time to begin troweling the mixture into the gaps between the parquet blocks. Get a large trowel or filling knife and begin troweling the gap filling mixture over the whole floor making sure to push the mixture into every last little gap or joint. Try and clean off as much excess filler as you can as this will make it easier not only to sand it off, but also to complete a second coat of filling if needed. You will only really need to complete a second coat of gap filling if there are any large gaps, or if you have added to much resin or water based filler to the dust when making the mixture. You should be able to tell when the first filling process is completed if you will need a second coat, such as if the filler has shrunk below the parquet blocks.
Once all the gaps between the parquet blocks have been filled and they are completely dry, then it’s time to start sanding off any excess filler left on the blocks. You should sand the excess filler off using a 100 grit sanding belt or as finer sanding belt as possible as this will normally be the last pass you do with a belt sander. Make sure you remove all the excess gap filler with the belt sander as it will be really hard to remove with the buffer which is the last process of floor sanding.
Remember that epoxy resin filler has a very strong smell to it and it is advised you have good ventilation when gap filling.