1. Stability of grass-roots units. Before construction, we should carefully check and confirm the grass-roots, check the smoothness, strength, water absorption of the grass-roots, whether the grass-roots is pulverized, loose, alkali return and other phenomena, whether there are obvious cracks, cracks (can be checked by watering the wall), whether the grass-roots is stable. If the base can not meet the construction requirements of putty powder for external wall, corresponding technical treatment should be done first. If the base meets the construction requirements of putty powder for external wall, putty powder for external wall can be constructed.

2. 基層的強(qiáng)度建議大于外墻膩?zhàn)拥膹?qiáng)度。按材料的粘結(jié)理論與實(shí)踐，如果墻基層的強(qiáng)度小于外墻膩?zhàn)樱鈮δ佔(zhàn)尤菀壮霈F(xiàn)“拔根”、空鼓、脫落現(xiàn)象。如基層強(qiáng)度大于外墻膩?zhàn)臃鄣膹?qiáng)度，則不會(huì)出現(xiàn)這些問(wèn)題。

2. The strength of base must be greater than that of putty. According to the bonding theory and practice of materials, if the strength of the wall base is less than that of the external wall putty, the external wall putty is prone to "pull out", "empty drum" and "fall off". If the strength of the base is greater than that of the putty powder, these problems will not arise.

3. 對(duì)界面的嚴(yán)格處理。先清除浮灰、油污（包括脫模劑），填刮基層的裂縫，剔出鼓包，如基層有明顯不平的地方，先用抗裂砂漿找平。如基層已非常干燥、吸水性良好，環(huán)境氣候也很干燥，就會(huì)影響到外墻膩?zhàn)优c基層的粘附力及強(qiáng)度，因此，建議施工前，可用水先澆濕墻基層后，再進(jìn)行外墻膩?zhàn)臃鄣氖┕ぃ绻麠l件許可，施工后2-3天，可噴水養(yǎng)護(hù)1-2次，防裂效果和強(qiáng)度會(huì)更好。

3. Strict treatment of interface. Firstly, remove floating ash and oil (including release agent), fill and scrape cracks in the base, and remove bulges. If there are obvious unevenness in the base, first use anti-cracking mortar to leveling. If the base is especially dry, absorbable, and the environment and climate are dry, it will affect the adhesion and strength of the putty on the outer wall and the base. Therefore, it is suggested that before construction, water can be used to pour wet the base of the wall first, then to carry out the construction of putty powder on the outer wall. If conditions permit, 2-3 days after construction, water can be sprayed to maintain 1-2 times and prevent cracking. The effect and intensity will be better.