Wall putty is also called skim coat, is a decorative and functional trowelling material for interior or external wall construction. It is applied to hide or remove blemishes or defects on the wall substrate’s surface to give them a smooth appearance.

Wall putty/Skim coat is one of the largest application areas of our MelaColl™ cellulose products: HPMC, HEC and MHEC. We have developed different grades of products with various properties to meet the needs of all customers. We also offer tailed formulations that can provide you with the most suitable products for specific raw materials and special local requirements.

Our MelaColl™ cellulose ether and Mikrant™ RDP products provide the following features for wall putty applications:


  • Improve water retention, sag resistance, crack resistance, and thickening effect.
  • Enhance the adhesion of putty to various substrates: MelaColl™ and Mikrant™ polymer powder have good thickening effect, It can enhance the consistency and bond strength of the wall putty, Suitable addition rate of it makes it has better adhesion feature.
  • Improve the consistency and stability of putty: MelaColl™ and Mikrant™ are vital key to adjust suitable consistency in fresh mortars. Suitable consistency enables fresh plaster to attach well on walls as well as to make surfaces smooth and be applied easily without the feeling of stickiness.
  • Provides putty with good workability: Better leveling and reduced stickiness of MelaColl™ and Mikrant™ can be applied easily to wall putty/skim coat, which easy to operate and construction, and can significantly improve the construction efficiency.
  • Improves hydrophobicity: After add the MelaColl™ and Mikrant™, the hydrophobicity of wall putty/skim coat has improved, waterproofing effect is significantly increased.

Summary of frequently asked questions

 What is wall putty/skim coat?

Skim coat is also called wall putty, is a decorative and functional trowelling material for interior or external wall construction.

What function does wall putty/skim coat have ?

It is applied to hide or remove blemishes or defects on the wall substrate’s surface to give them a smooth appearance.

What effect does MelaColl have in skim coat/wall putty?

---Water retention, sag resistance, crack resistance, and thickening effect.
---Enhance the adhesion
---Improves consistency and stability of putty
---Improves open time

Why does putty peel off?

1. Insufficient stirring after adding water, the additives do not fully play their role.

2. In the final step, the worker scrapes too many times, causing a slight peeling of the base surface. After drying, the putty will be powered off.

3. The base surface is too smooth. The adhesion between the putty and the wall is not enough.

4. The putty is too thick. The surface is dry but the inside not. The overall shrinkage is inconsistent will cause cracks.

5. Brush the putty again before the previous one dries.

6. The base surface is dirty, putty does not stick to the wall.

7. The base surface is uneven. The thickness of putty is different, and the drying time is inconsistent, cracks will appear, just like No. 4.

8. The wall is too dry. The putty does not have enough time to cure since the water is lost too quickly.

9. High temperature, strong light, strong wind cause the water lost too quickly, so the putty does not have enough time to cure.

10. Low temperature, high air humidity. The putty cannot be dried in time, and is easy to separate from the base surface.

11. The base surface has cracks without treatment.

12. Add too much water to the putty. If the putty is too thin, it is easy to cause large and evenly distributed cracks after drying.

How to deal with the powder off?

1. Mix and stir, waiting for 10 to 20 minutes, and then stir again to use. The ratio suggested is putty powder: water = 1:0.5. Please refer to your construction consistency.

2. If the base layer with strong water absorption, please wet it with water or sprayed it with glue in advance. The consistency is suitable for construction.

3. The newly plastered cement wall should be putty after the curing period.

4. Surface treatment to ensure that the wall surface is smooth and no cracks.

5. The number of scratches is usually two batches, and the second coating can be applied when the previous is dry.

6. The thickness of batch scraping is 0.8~1.5mm, and the dosage is 1~1.5kg/㎡.

7. Construction is suitable at 5℃-35℃.

What is the function of RDP for wall putty?

1. Improve the compressive strength, bond strength, water resistance, and constructability of putty.

2. Effectively reduce cracking and powder off, prolonging the service life of putty.

3. Reduce the cost of packaging, transportation, and maintenance.

4. It has good freeze-thaw stability. So no need to consider the erosive effect of microorganisms.

5. Non-toxic and non-polluting.

What is the function of HEMC, HPMC for wall putty?

1. Thickening: Keep the solution uniform and consistent, and resist sagging.

2. Water retention: Extend the open time, so that the lime calcium can react more fully.

3. Warkability: Make the putty powder have good workability with its good lubricity.

Why is my putty yellowing?

1. Simultaneous construction with polyester paint (paint) or release agent. They will cause the putty to yellow.

2. The base layer has oil or other grease stains, causing the putty to yellow.

3. The putty is polluted by rust or other colored substances.

4. The temperature is too low (below 5℃).

5. The base surface is too wet.

6. Scraped a second time before the previous dry.

How long does it takes for putty to dry on a sunny and dry day?

Open the window and it will dry in about 3 days.

 Scraping the putty again before the first one drying, will it affect the quality?

It will cause problems such as wall cracking, peeling, hollowing, and yellowing. Please do not do so.

What are the key advantages of waterproof putty?

1. Strong adhesion, high bonding strength, certain toughness, and good air permeability.

2. With the strong water resistance, it will not chalk after getting wet.

3. No cracking, peeling, peeling ...

4. Helps your wall to delicate, soft, and has a good texture.

5. With water-resistant putty, spots can be directly scrubbed or painted with interior wall paint.

6. Improve the performance and service life of coatings.

7. When painting the interior wall again, you don't need to remove the wall, just brush the interior wall paint directly.

8. Water-resistant putty is an environmental-friendly material, it does not harm health.

9. After the putty is dry, a lot of powder falls off when I rub it, is this normal?
    If it is powdery without polishing, it is unormal, and needs to be shoveled out and redone.
    If the powder appears after polishing, it is normal, and it should be cleaned before latex paint.


+86 531 87919350 (Beijing Time: 9:00-17:00)

melacoll@mikem.com (China office)

RDdept@mikem.com (US R&D office)

China office: Jinan University Science Park, No.988 Shunxing Road, Jinan, Shandong, China.

Headquarter: 5955 Alpha Rd #1209 Dallas, TX 75240

A True Business Partner.

Leave Your Questions, We Will Contact You Within 12 Hours. Please Pay Attention To The Email.

Contact us

Copyright © 2020-2022 Melacoll | All rights reserved.