Cracked floor screed indoors: what to do
The building moves, the screed breaks, is it possible to fill the cracks with sealant, and apply a primer and subsequent layers on top? Cracks were filled with a primer; they still crack. Will our coating crack in the future?
Kseniya
Expert Answer
Good afternoon, Ksenia.
If the house "walks" to such an extent that the screed crack on the floor, only major repairs will help. First of all, you should inspect the old base, clean it from cracked cement-sand mixture and remove the screed where it has moved away from the concrete slab. By the way, if the floor surface is in a satisfactory condition, and the exception is small local areas with a “coiling” screed, then it can be repaired. For this, the cracks need to be expanded and filled with a special polyurethane sealant. Such two-component mixtures have excellent fluidity, penetrate well into cracks and due to high adhesion firmly connect the exfoliated coating after setting. The advantage of injection repair compounds is that after drying, they form not only an extremely durable, but also quite plastic mass, which will not crack and “play” in the future.
Further restoration work should only be started after the floor surface has been thoroughly cleaned of debris and dust.
Do not be lazy to soak the concrete base with a deep penetration primer - it forms a polymer “crust” on the surface and ensures good adhesion between the layers. After that, a steel armo-belt is laid on the floor and poured with a layer of a new solution. What to use for reinforcing - a stucco grid or a welded construction grid - you decide. It all depends on what scale the problem you described reaches. In any case, it is necessary to make reinforcement, since metal is the only thing that can save the screed from cracking.
If the described method seems to you too complicated, then you can always perform minimal alignment and lay such materials as a laminate, parquet or parquet board, deck board or panels made of polymer-wooden composite. It all depends on the purpose of the room and your personal preferences.
