Priming of surfaces before painting or in the process of conducting putty work is a mandatory step. Some primers have long enough expiration dates, others are stored without harm for the quality of the product less time. Let's see what period of time after the indicated storage period, these building materials can be used for priming walls.
- Duration of storage of primer mixes without loss of quality
- Basic requirements for
- primer When using soils that have been stored for longer than 18 months
- Masters advice
Duration of storage of primer mixes without loss of quality
If stored correctly, the expiration date specified by the manufacturerMost primers designed for painting and putty work, without losing their basic qualities, is 18 months. Some manufacturers offer soils that have longer shelf life and are 24 months and longer from the time of manufacture.
It is possible to use soils at the end of this period only after checking their quality. In case of discrepancy of priming mixtures with the basic standards of technical specifications, the manufacturer must replace them within six months from the moment of shipment to the address of the consumer.
Basic requirements for soil
Chemical building mixtures intended for priming walls, as well as any other building materials, must comply with certain technical conditions:
- The drying time of the undercoating film must not exceed 24 hours at an ambient temperature of no higher than 4 degrees Celsius,and at temperatures from +4 to +25 ° C - no longer than 8 hours.
- After adding hardener to the primer, it must be usable for 8 hours.
- Protective anti-corrosion properties of primers should be maintained for three years.
- Priming building materials should be a homogeneous mass, without lumps or stains on the surface.
Primers that do not meet the specified requirements, can not be used for painting and plastering walls, as they can not provide the required quality and protection of the surface.
When to use soils that have been stored for longer than 18 months
The shelf life indicated on the package by the manufacturer of the soil only indicates the period during which the product can be stored without loss of the factory-guaranteed qualities. Usually, after the indicated period, the loss of quality by chemical building materials is below acceptable standards.
Naturally, a slight decrease will not greatly affect the primed surface of the walls. In the event that the required properties( drying speed, polymerization, protective functions) have been lost, the primer can not be used. Overdue primers can be used if:
- During the entire storage period, the integrity of the packaging has not been impaired and the product has not been exposed to the environment.
- The primer was not poured into another container during use.
- The material was not frozen or overheated during storage.
- If no abnormalities are found in the visual inspection of the primer mixture( the mass looks uniform, without lumps and film on the surface).
Typically, chemical building mixtures are stored for much longer than the manufacturer's indicated shelf life. The worn out primer can be easily distinguished visually from the one that is still usable.
At some point in time, the loss of the basic properties and qualities of these chemical building materials reaches their limit, after which the overdue primer becomes completely unusable. Signs on which it is possible to determine the change in the quality of the primer mixture:
- , it is stratified and a dense insoluble precipitate is deposited on the bottom of the container;
- , a film or spots formed on the surface;
- it contains lumps and seals;
- has a strong marsh odor;
- it is too thick.
- If the overdue primer intended for covering the walls is too thick, it can be diluted with a solvent( it is important that the solvent has the same basis as the soil in its composition).
- For the covering of walls it is possible to use soils with insignificant loss of properties. For example, if the mixture began to dry for two hours longer, but at the same time meets the remaining technical requirements, there is no reason to refuse to use it.
- Only primers can be used that are designed to directly cover the material that the surface of the walls consists of. That is primed for economic reasons, the walls, lined with metal profiled plates, expired soil, originally intended for the treatment of wooden surfaces, is unacceptable.
- If in the process of priming works you have to purchase additional mixtures, you should take materials of the same brand that was used earlier.
When deciding to buy new primers, or to use the savings from the ones that have long been stored, you need to weigh the pros and cons sensibly. Given that chemical building materials are relatively inexpensive, it may not be worth the risk of all repairs, in order not to correct the result in the future.