毛坯墙凹凸、石膏板接缝、阴阳角歪——很多人一袋石膏粉全屋厚刮，结果两个月起壳开裂。石膏和腻子不是同层替代关系：石膏吃落差，腻子收表面。

Uneven rough walls, gypsum board joints, and crooked corners - many people scrape the entire house with a bag of gypsum powder, resulting in cracking of the shell within two months. Gypsum and putty are not interchangeable in the same layer: gypsum has a height difference, while putty has a surface finish.

一、建筑石膏粉的三类分法

1、 Three classification methods for building gypsum powder

粉刷石膏（底层/面层，GB/T28627）：墙面顶棚大面积找平，底层单遍5–8mm、总厚可到20mm，微膨胀抗空鼓；

Gypsum plastering (bottom/surface layer, GB/T28627): Large area leveling of walls and ceilings, with a single layer of 5-8mm for the bottom layer and a total thickness of up to 20mm, with slight expansion and anti hollowing;

嵌缝石膏（JC/T2075）：专补石膏板缝、钉眼、V型槽，快硬高强，别拿来满墙批；

Jointing gypsum (JC/T2075): specialized in repairing gypsum board joints, nail holes, V-shaped grooves, fast hardening and high strength, do not use it to fill the wall batch;

轻质抹灰石膏：加气块、顶棚轻量化找平，容重低、保温好，但强度低于重质底层。

Lightweight plastering gypsum: aerated blocks, lightweight leveling for ceilings, low bulk density, good insulation, but lower strength than heavy base layers.

二、和腻子的边界

2、 Boundary with putty

墙面误差>3mm：先石膏找平；误差≤2mm：再上耐水腻子薄批两遍。拿腻子厚填线槽、拿石膏当面漆底层直接刷漆——都会分层、透底、龟裂。

Wall error>3mm: Level with gypsum first; Error ≤ 2mm: Apply two thin coats of water-resistant putty. Using putty to fill the wire groove thick, using gypsum to paint the bottom layer directly - both will result in delamination, penetration, and cracking.

三、石膏的死穴：不耐水

3、 Dead hole of gypsum: not water-resistant

气硬性材料，软化系数普遍0.3左右，厨卫淋浴区、外墙、长期返潮地下室禁用；非淋浴潮湿区可选耐水改性款，但别当防水砂浆用。

Pneumatic materials with a softening coefficient of around 0.3 are generally prohibited in kitchen and bathroom shower areas, exterior walls, and long-term damp basement areas; Water resistant modified versions can be selected for non shower damp areas, but do not use them as waterproof mortar.

四、施工四条红线

4、 Four red lines for construction

混凝土/加气块先刷界面剂，防鼓泡、防失水开裂；

Apply interface agent to concrete/aerated blocks first to prevent bubbling and water loss cracking;

厚了建议分层，单层不超8mm，前层终凝再上后层；

Thickened layers must be layered, with a single layer not exceeding 8mm, and the front layer will eventually solidify before the back layer;

初凝浆料绝不加水复用，搅拌后40–60分钟内用完；

The initial setting slurry will never be reused with water, and should be used up within 40-60 minutes after mixing;

5℃以下、湿度>85%、穿堂风直吹——停手，不然必裂。

If the temperature is below 5 ℃, the humidity is above 85%, and there is direct wind blowing through the hall - stop, otherwise it will crack.

五、采购看包装不看名字

5、 Purchase by packaging, not by name

认执行标准（GB/T28627或JC/T517/2075）、第三方检测里的粘结强度/保水率/凝结时间，济南本地有干粉线、能小样送检的厂，比只报“石膏粉每吨多少”的散户稳。

According to the implementation standards (GB/T28627 or JC/T517/2075) and third-party testing, there are factories in Jinan that have dry powder lines and can send small samples for testing, which is more stable than those that only report "how much gypsum powder per ton".